LEE os GY OL LE BY _ EAR 19017 R.A (TUTE OF TEC r INS’ C ove . Ky f J UM KMOL Ea 7 r i K XN 537 ‘ JIRA MC AT 445 Earle, R. H. The Morkrum system of printing telegraphy ; Mk ra i ne a matt ‘ THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY A THESIS PRESENTED BY RALPH H. EARLE AWOL she PRESIDENT AND FACULTY OF ARMOUR INSTITUTE OF TECHNOLOGY FOR THE DEGREE OF BACHELOR OF SCIENCE IN ELECTRICAL ENGINEERING MAY SY, S17 ie Tne e aa of Ce etri LA AAAL Engineering, ILLINOIS INSTITUTE OF TECHNOLOGY Dean of Engineering Studies PAUL V. GALVIN LIBRARY 35 WEST 33RD STREET ae CHICAGO, IL 60616 is RP Ci Ong Wicgieg saa f ME : a, yoowOniss STUART ane ee RANE ii ae rele te 10 waray 2 iaisitNe: aH YEIASO OaLaT OMITATAT | ey THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY OBJECT, The object of this thesis is the composition of a detailed descrip- tion of the Morkrum System of Printing Te- legraphy. weed’? "i ie 6 YSTARVERIZT DUITMIAL WO METCYe MUAAAOM FET .TORGLEO ateedd atdt to toetdo edT ~qitsash fhetiateb s to nottteoqmoes edt at -eT agittaizvi to meteye mrrdroM ext to sort “qstael TTS THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY FOREWORD. The material for this thesis was obtained from the Morkrum Company, al- though the wording and arrangement is orig- inal with the writer. A number of the draw- ings of this thesis were also obtsined from that company. R.H.E. YHIAADSINT DMITMIAT TO METAY MUAAAOM AH? . THOWEAOT eteeds atdt tot [strotam oft -f[8 ,yaeqmod aurrvtroM edt mott heatstdo saw -gito at tmemegnatia bas anthrow edt dgyodt -wath edt to tedmum A .tetiaw edt ditw [sat mort bentetdo oefe stow atesdt atdt to egat -Yasqmoo tat 2.8.8 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY Table of Contents Part I - Introductory GENERAL - = = = = = = PRELIMINARY SYSTMM - - - - SECOND SYSTEM - = = = «= THIRD SYSTEM - - = = = = FOURTH SYSTEM - = - = = FIFTH SYSTEM - - = = = = SIXTH SYSTEM - - - = = «= Part II - THE TAPE = = = = = © «= THE CODE - -© = = = = = THE PERFORATOR - © - = = GENERAL LAYOUT - - - = = THE PUNCH PINS - - = = = THR HAMMER - - - = = = THE PUNCH LEVERS - = - = SELECTIVE MECHANISM - = - TAPE FEED - - = = - = = p.3 pe? p.8 p.ll pe2l pe25s pee? Perforator p35 p.37 p.39 p42 p42 p47 p.49 p.50 p.56 YHTARDSIST OMITUIAT IO METeYe MUSDINOM FHT &.q Y.g 8.9 {[l.q [s.q as. TS.q rsotatottel Shed TS. e5.9 Sh. Sh.q VS.q es.g 03.q aa. atoaetmod to afdet yrotoubottal - I trsf Be Or ee ee a net) a a SOLE SD MPC YE YHARTMLISAL oP oO a ee “PETS “MOORE Se Be Va Se Oke oe Nee fide oe le Ee eee ET aha ie) ey ie EE SEES - = «= « = = = MaTeYe HIXIC bas ,ebod ,eqeT - II traf ae we we Se wy ee ep a oe ta aD et ke i er =~ = = « s s §ORAROTIET Tat ~ - = = «= = QUOYAL CATHWRS - + « = « = @NI¢ HONGT BHF - = = = «© = = SEMMAR DHT - = = = © @SHVEI HOWUL FET - = «= = M@IWAROSM BVITORIAG we wee ee ee ae THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY Table of Contents (Cont'd) BAM OPUARR RO ea oe ok ee END-OF-THE-LINE INDICATOR - - - p.60 Part III - The Distribution System GENERAL - - - - - = = - = p.68 MOTOR - - - - - = = = = = p.69 TAPE CONTACTS - - - - = - = p.71 TAPE FEED - - - = - - - = p.73 WOANGULGSION). 4 =. 4 je = =. = p.78 AUTOMATIC STOP - = = - = = = pe79 CUT-OUT - - =- = = = = = = p.85 TRANSMITTING DISK - - = = = = p.87 POLE CHANGER RELAYS - - - - = p.90 RECEIVER DISK «© - - = = = = p.92 TRANSMISSION SHAFT = - - - = = p.93 SYNCHRONIZER - - - - = = = = pe94 DISTRIBUTOR CIRCUITS - = - = = pyl04 VHUAAORINT QUITUIRI TO MET eYe MUAXFOM FET (a'taxod) ataetnod to aldaT S8.q - - soe oe el = (om emoAde wOoAT Odiqg - =- = HOTADICHT SUL I-HH?-TO-Cuz moteye mottadiutet® ed? - IIT treT Ric - > + < 2s > Cana ae be ae el at a ee ne HR [Vi@se ou we ab = ¢MOIMAHOEM moTOmITze atic se » + s » SPOON MOTOMIEE Yal.q - <= = STs oero MERE mOTORETS OFq a+ .-raeegere er Pecee ROME ROTATOR avi.g 4 - - - - = AMHOAG GMA ABDATE Glia - = sat entetaqcs to peoetg wert ‘ow? Dentelqne et | .Dedtressh od biedte eookveb wen “ott 0 text oat 22 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY is a relay pole chenger. This is an ordinary Felay.equipped with both front and back con- tacts. When the relay coil is not energized, the armature remains against the back contact, but when the coil is energized, the armature is drawn forward against the front contact. The other new device is a polarized relay. This relay has an armature which plays between two contacts, but has no retractile spring. When the coils of the re- lay carry current in one direction, the ar- mature takes position against one contact. If the coil current is reversed, the armature goes over to the other contact. Since there is no retractile spring, when there is no current in the coils, the armature remains against whichever contact it happens to be. With this understanding of these new instruments, we can take up an ex- Ss YEIAROAIAT OQUITMIAL 20 MeTeye MUSAHOM FHT yrsenibro mea ef aftdl .teansdo efog yeler a at -~aoo dosd bas sgaort dtod dttw beqdtups, ysiet Sesisrene tom et [foo ysfer oft medW¥ .etost eTostaon Moad edt tenters eantamet ovetamre oft ersteants. oft ,.besigrtone et ftos eft sodw tod ,toataoo txort edt taniess brawrot ovatd et s ef sotveb wen teito ext evutemrs me eat yelor eifT .yaelort besirelog on sad sud ,etsstaos owt neowted eyslq doidw ~9t edt to eftoo edt aefY .anitrqe olitosrtet -rs edt ,mottosrt5 eno mt tieriso yriso ysl tI .toetnos eno tantegs coftteog eevest eryteam ermteacre eft ,berrevet ef tasiis9 [too ait otedt esatt .testmos sedto eft ot tavo ae0g on ef etent sorw ,gnizrqe eLitosrter om at eniamet ettanre edd ,altoe eft at trerise od ot snogqad tt testnoo revetotdiw tentays f to gatineterobang eidd Atty ~-xe fs qy eist mso ow ,eineswittant wen evedt - BD gd a (Lg THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY planation of the new scheme, As in the pre- ceeding system, there are the tape contacts. These contacts do not, in this case, control the line impulses directly, but do so through five of the relay pole changers just describ- ed, one pole changer being provided for each of the five tape contacts. Each set of relay coils is connected to the local battery by means of its own tape contact, so that when the contact is open, the relay is not ener- gized and the arm ture remains against the back point; when the tape contact is closed, the relay is energized so that the armture is drawn over to the front point. The current path from the back point of the relay pole changer is to the negative side of the mrk- ing battery and through the battery to ground. The front contact is connected to the positive side of the spacing battery, the negative side 23 és YHIALOLITT HPUITHIAI TO METeYe MUSMAOM HT -erq edd at eA .emonoe wer eft to notiansi¢ .eteostaos oqat oft ets etedt ,meteye anthes fortmeoos ,saso etht at ,tom ob etostmnoo seodT _figsorlt of ob ted ,.yftoertS seeInqmt oentl edt -diroeeh tant etesmsdo efoq yelet edt te ovit dése tet bebtvorg ented texzmedo efog sro ,be yelet to tee dos® .etoaetmon eqet evit edt to yd yrottead Isool edt ot Hotoonnoo ef elroo nodw tsdd og ,tostnoo eqst mwo efi *o ensom «teme tom ef yvafer ef? ,.mego ef toatnoo eit ext tentage ertemer eroterrs oft bee bests ebesols eat sostmoo erat oft todw ,tatog aoad emtenre oft tedt oe bestarene et yslet edt tasrtys of? .tetog taort edd ot revo mwerh et eLoqg yalet eit to tatog xoad oft mort Atsq -tzam eft to obta evitagea edt ot ef teanado Aavors of yrettad ont davordt Bas profiad gat evittnog edt ot Betooktroe et toatmoo tnort ed? ebte evisazen edt ,yrotted grteaqe edt to ebte THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY of which goes to ground. The armature is con- nected to one contact button of the transmit- ting disk. The revolving brush arm is connect- ed to the line. A consideration of the trans- mitter circuit shows that with a tape contact open, @ negative or marking line impulse is sent out, and with a tape contact closed, a positive or spacing impulse is sent out. Thus, the tape contacts control the character of the line impulses. At the receiving station, the line is connected through the operating coils of a polarized relay to ground. Therefore, a positive current pulse throws the armature to one side or point, whereas a negative pulse throws the armature to the other point. One point is dead, the other point is connected to one side of the local battery, and the ar- 24 .RAE on ee Sey eee De | Tomer SS YHIAROAIGT OUITMIRI TO MATAYe MUAAHOM RAT -f09 eft erstemrs 6X? .foayora oF goog dotdw to -timenett odt to nottud tostmos. emo ot hotsoen -toentos et ore devid entvfover edt .welb satt ~oait oft ot bo -ecstt ot to cotiarsbienos A tostiros eqat es ditiw tent ewore tinotto tett ta ef eeluqmt satl antvren to evitenen s ,asdo s ,boeofo tostros saat s dtiw ins , tro tree end? .dso tase af eafmamt sxtésqe to ovitteog to totosrads odd L[ortmoo atostado sqst edt -boaluqmk exrfl edt eft ,acottate satvieser eft tA aftoo gattsteqo edt dasotdt hetoonnos et enlkl ‘8 ,9toteted? .bavors ot esler BSositefog s to ot erstemrs eft ewortt saluq tnevttyo svitteog seflouq evitsgen es agsetedw ,tatog xo shite emo em0 .tatog teddo edt ot srutemrs oft ewordt hetsonroo at tatog tedto edd ,beeb et! tatog | ~-ts edt bra ,ytettad [sool edt to obta emo ot 25 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY mature is connected to the receiver brush arm. The receiver relays are connected between their respective control buttons and the free side of? the local battery. As for the operation of the receiving apparatus, suppose a spacing or po- sitive line impulse appears. The armature of the polarized relay goes to its dead contact, so that no local relay is affected. Suppose a negative or marking interval next appears. The armature of the polarized relay goes over to the opposite point, which is connected to the battery. The local relay is energized, and in- dicates a signal. Thus, in this system, the local receiving relays respond only to the marking intervals, just as was the case in the former system. FIFTH SYSTEM. Fig. -5 shows a still further development of the system. This 3s YHCAADATET OUITMIAG TO MATSYe MUSAHOM GHP ars desxd tevteost edt ot hSetoonmog al etutam tlad¢ meewted betooamoo ota ayslet tevieoss edT ebte sett oft bus enottad Lottaoo evitoeaaet -Yiretisd L[seol edd to edt to aottareqo edt tot eA -“O¢ £0. uttosqe = esogare ,astarsqgs.3anivisset to eretsore edT .etseqqs salfuqmt eati evitte -tostmoo baeb att ot e903 yslet bestisloq edt ‘8 esoggue ,betoetts at yslet Leool om tedd o@ edt ,etaeqqs txen [sevietat gatizrem to ovitegen ot tevo sesog yeflot besirsiog edt to etetamta edt ot Betoonnoo et dotdw .tatog sttaoqqo edt -xt Bue ,bosigrens ef qelot Leool of? .eretted odt ,meteye sid ot ,erdT .feagte es eetsoth edt ot ylmo Dbaoqeet eyslor goiviooet [anol edd mt ezeo edt sew es.taut ,alavretat gottrem eit smeteye temtot 8 ewore a..ght .METEYE BTWIE, oo op dey oy eka? smoteye odd to tmemgoleved tedéuut [Lite - Reale Pipe "ete tege re 6 AA 8 ea 26 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY scheme is the same as that of Fig. 4, except that the line signals are sent out by a main- line pole changer, controlled by the relay pole changers, instead of being sent out by the relay pole changers themselves. This main line pole changer is merely a polarized relay with its operating coils connected to the bat- tery through the relay pole changer contacts, its armature connected to the line, and its two points connected respectively to the spac- ing and marking batteries. The other sides of the batteries are grounded. The operation of the system is apparent from the diagram. This system possesses two ad- vantages over the former one. The first is that the number of contacts in the main line eirecuit is reduced to one, viz., the one at the main line polechanger. Under adverse con- ditions of operation, this feature is of no YHIAMOSIAT DUITUIAL TO MATeYe MUAAKOM AAT tqooxe ,$..9f% to gedtd es emee odt et emesioe -ntea s yd two tooe ore efengte enti edt tert yelor edt vd beflertaos .,tegmads efoq omit yd tuo tase aniesd to hastack ,etrenasde efog xten efdl .eevicemedt eregmanio efog yelfst edt yeler besitalog 2 yletom at tegaarto efog entl -tsd eft ot Betoonmoo eftos aniiatsqo eth activ eevostaco tegnsio slog yalst edd dgvordt yret att Bers .,ertl ett ot betoernoo srstanre ett -osge edd ot ylovitoeqass betoonmoo sitmtoq ort to ashtea redto sf? .eetrettad ertiem bre ant to motteteqo eft .bobnsorg ers seitotiad ent msigeib eft mort tnersqqe et moteye oendft -bg owd eeaeoacog motera etal. eb tenit edf .eno semrol edt revo segadasy entl nism edd at etostnos to tedmua sdit tedt ts emo oft ..siv ,esmo ot heouber et timorte ~mfoo setevbse refhsU .teudadosfog entl atam ent om to et etwitsst etd? ,cotteree to anoltis | ne THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY little importance. The other improvement appears when & number of marking or of spacing inter- vals are transmitted in succession. The main- line-pole-changer armature retains the same position throughout the series; hence, the line current is msintained constant at its full value throughout the series. Current lag therefore does not oceur except when succes- sive impulses are of different signs. SEXTH SYSTEM. The final de- velopment of the system is shown in Fig. 6. The scheme of Fig. 6 is the same as that of Fig. 5 except for two changes in the receiv- ing apparatus. These changes still further decrease the possibilities of wrong inter- pretation of the incoming impulses by the receiving apparatus. The first change is the fact 27 RIAU a on ¥ ¥ +S YHIASOAIAT OULITHIAL TO MITeYea MURAHOM FHT ~eomatroqmt eftrit aveeqys tromsvorqmt refto ex? -rotait satosqe to +o satvtem to tedsaur 8s nedw -ittem efT .moteseoone at betttmeratt ore elev amsa edt entater otvtamra rsanedo-elog-ontl edy ,esonead :eetrsa edt tuodasotdt soréieoq ett ts tuatenoo heatetrtam at toerryo entl gal twermy) .eetres edt teorgcordt eslav Lint -seooua medw tqeoxe rwo90 tom Beob etotetadtt -erate dustottibh to sts eselsqmt ovte ~9h [entt eff .MaTeYe HTzre .o gli mr awonde et moteve edt to taemgolev to tadt es omee oft at 3 .gtl to emofoe eT -viesot oft nf asanredto ovt tot tqesoxe & .2tF tentryt [ftte eogreto eaedt vewdereqas ant -totot acotw to asttilitdiseog sit sasstoob ont ™ ag gntmoont edt to nottatera ,artevag¢s aatvtsoeT tost eft ef egmeads tarit’ edt °° Gris 28 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY that the receiving polarized relay does not control the five simple relays directly, but instead, controls an exactly similar polar- ized relay, which, in turn, controls the five simple relays. This working is plain from Fig. 6. The second change is shown sthematically: It consists of an adjustment by which the receiver disk can be moved for- ward in the direction of rotetion of the brush arm, or can be retarded against the direction of rotation of the brush arm. The total angle through which the disk may be turned is perhaps forty degrees. The reason for this modifi- cation may best be studied from Diagram (e). This diagrem is the same as (a) as far as the wave form of the impulse is concerned. It will be noticed from the diagrams that the o or.) YHTARDALAT OMITAIRY TO MATeYe MUAMHOM AAT tom ee0b ysfer bestrsfoq grnivieost eft tedd tod ,vftoorth ayelet efqmte evit edt L[ortmoo -telog tafimie yitosxe os efottmoo ,Ssetent evit edt afortmoo ,mivt af ,doitdw ,yelor best mort atefq at anttxow efd?..aysfor olqmte od 2 Blt awode alt eanesdo Bboooee edt tohemtesths os to atetasoo ti ehiab hdomeche =Tot bevou ed aso welh xevieoet edt cotdw yd oft, to gottstor to mottoetlh edd at braw edy tantsss bebrster ed mae to ,mts deotd eft .mte davrd edt to mottator to mottoortb ed yam delb odd dotdw davords ofens [stot .8eetgebh ytiot aqedteq at heawt -fithbom eldt trol noeser off | a (a) mesnelt, aoxt hetbute ed jisili tena pakie as ist a2 (5) ee omsa, eft at merasth atdT -beateonros at salngqmt odd to mot evew edt odd tadd amatgetb edd mott beotton of Lftw tT THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY impulses are quite jagged and irregular. The irregularities may produce a slight flutter- ing of the armature of the receiving poler- ized relay, especially near the transition period between positive and negative pulses. This fluttering is not of sufficient magni- tude to throw the armature from one point to the other, but it is great enough to produce @ poor contact. Such a contact would not be desirable in the circuit of the simple re- lays. A remedy for the uncertain contact in the circuit of the five relays is provided when the second polerized relay is added to the scheme of Fig. 5. This relay does not change its position unless the main line relay first changes; any fluctuation of the armature of the main line relay less than a complete movement from one point to ao YHIAAOAIAT: DUITMIAT TO MITeYe: MUSAAOM SAT eit .xsisgetrt bas begast stiup ers sealngmt -totiolt tigtfe e soyborq vem esititelsgetts -tsfoq anivieser edt to exsteagre edt To gat cotétenart edt rsem ylistoeqes ,yslert best -2oeling evittegon bus ovitteog neswied botreq ~ hagent dnetorttwe to toa at gitretiolt etdt: ot tetog emo mott etutenrsa oft wordt ot ebst eosborg ot agvone testa et tt tud ,zredto eft ed ton bisow tomtnoo e dowd .tostmoo to0g # -ot efqmte edt to ttvorto edt mt efdarteeh 2ayst mistroons eft trot chenen A et ayslet evit edt to tiverto oft af tostnoo- et yeler beaiteloq baosee edt sodw bebivorg ysfer etd? .¢ .gft to -omadoe oft ot bobbs tem edd eaotar moitkeod ett egaaedo tom aeoh rottevtor ft wae jgooguedo text ysfer extl seel yeler onfl aten eit to ervteanrts eft to. ot totog exo mort tmemevom etof[qmoo s aadt THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the other does not affect the second relay. The armature of the second relay possesses sufficient residual magnetism so that the contact is kept firm. Hence, any flutterings of the main-line-relay armature do not af- fect the local relays. The impulses in the local ecireuit, with the plan just described, are shown by the rectangular full-line pulses in (e). The transmitted pulses are shown dot- ted. It will be noticed that the received pulses are fair reconstructions of the trans- mitted pulses, but occur at a slightly later time because of current leg. The second change in the sys- tem, viz., the angular adjustment of the re- eeiver disk, allows the middle, or fullest portion of the pulse to be utilized. This fact may be understood by a reference to (e). 30 YAUAASIIAT DUITMIAL TO MTeYe MUAAAGM, EXT -yslert baoose edt tootts tom seoh tedto seit seeeoceeg yelet Baoosa edt to otstants.edT suit tedtt of mattengsm [evbleer taotottise eativedtult yas ,eomeH smrtt tqed.ef tosiaos ~te ton of etrtanre yelor-onti-ntam odt to -aysiet.fsool edt toot [sool sndt of eselvqmt odT ete ,Sedirecebh text melq odt dtig,,divotis seelua enti-[ist realugnestoet oft yd owode -tob.owode ere esalug bettimanet? ef? .(e) ot hevteset edt tedt beotton od I[ffw tl. .het -~anett edd To anottiouttesooer riat ots seelugq totel vltdatia se ts.rs990 dud ,,sceluq.hbottim +3al daettso to eaueced omit eye odt af egdedo broooe, eff ¢ -ot sdt to.tnomtartbs telwgne edd ,.atv ,mot teaelint +o ,ofhbim edt ewolls.,veth.revieo etdT ,boalliss ed ot eelsq eit. to nobdrod -(9) ot eonsreter s yd booterehny od yam toet. rei dak RN aly et Bet, 31 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY This diagram shows the puls- es, and also shows the buttons of the receiv- er disk developed, or rolled out, just below. The buttons are drawn in to such a scale that the diameter of each button represents the time of brush-passage over that button, and the dis- ‘iste between buttons represents the time re- quired by the brush to pass from one button to the next, The buttons are small compared to the pulses, and that portion of the pulse ly- ing directly above each button is the only portion utilized; the remainder of the pulse occurs while the brush is between buttons. By sliding the entire row of buttons along under the row of impulses, we can make any button receive any part of the impulse series. This condition can be actually duplicated in practice by the revolution of the the disk upon which the buttons are mount- ed. However, in practice it is never desired VEO SN eee Nae “ aot ta ee Lé YHUARPRLIGT SYITMIANG TO MITSYE MUHAROM FHT -elyg edt ewode mergsths etd? ~visset etd to exotiud edt ewodea oels bre ,.ee -wofed teug ,vso beffor to ,.beqofeveh wetbh re tadd efsoe s dove ot wk mrerh ete enotinud sa? enmtt eft trosetqet cottud dose to tetemsibh oft -elb edt fase ,mottud tsdt sevo spseasa-deuxd to -9t omt? edt etroeetasr enottud seswied deuau mottod ero mort sesq of Senid sit yd berfoo od heteqmoo fIsme ers eoottud ent? .txen edd ot ~vl sefoq oft to mottroq teintt bee ,ssetuq oft yino ett ef sottud dose evods ylteerth ant selug edt to tshotemer elt ;bost Lita noftrog ya .enottnd meewted et deurd eft elidw ersooo tebas gnofe snotiud to wor ertine edt satbita _tottud ye ever mao ew ,seatuqmt to wor odt esettse sefuqmt odd to treaq yas evteser qvifisotos od neo cotifinoos eid? } to sottsefovet edit ydiseltsatq at hetsotiqnb -tayom era esotdud edt dotrlw soquy dath ett oft _ betig0es teven ef tf eottoestq at ,tevewoH .be 32 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY that an impulse be received on any but its own button. Hence, the angle through which the disk turns is only sufficient as to al- low each button to receive any part of its own Lhpelee: with a little added leeway in both directions of rotation. The results of such an ad- justment of the disk are two in number. The first is that the disk can be adjusted so as to admit only the peaks of the impulses. Hence, with the aid of the two relays on the line side of the disk, greatly distorted im- pulses can be correctly interpreted. The se- eond result is that on long lines, where the current lag may produce quite a lag of re- ceived pulses behind the transmitted pulses, the receiver disk can be rotated backward un- til the brush-and-button contact occurs at the same time as the reception of the pulse. St YATASOAIAT OUITMILI LO MATeYe MUAAAOM FHT eti gud yne mo bevitsoet 6d eelfsqmt os tadt doidw desotit efane ett ;,sorol .motiud mwo -f3 ot es toetotttue yino ef anit weth edt eti to dteq yas eviesset ot mottud dose wol ct yswoet bohbs efttil s dAtiv aetnent Fea se) nokteter to anottoorib dtodd -ba ae dove to atiueet off edit .tedmua mt ows ors Heih ont to toomtent oa betarthe od aso death edt tedd ef terlt -goniuqmt oft to etesq edt vino timbe ot as edd mo eysiet owt ett to Ste ent dtinw ,eonel -mt hetroteth yfteerg ,deth edt to ebte enti ~e3 ed? .betetagtetat yiteerroo ed sao eselig edd eredw ,eentl smof mo tedd ef diveet bros -et to gel s etimp souborq yee asl trerivo ,eeciug bottinenert edt Satded easeinq bevies -ms hrawNoed hotsator od mao Heth revieser oft te exrsooo toatmoo nottud-bos-deotd eft Ift -cafeq edt to morttqeoor eft es emtt omse ont _ aie tare) 33 THE. MORKRUM SYSTEM OF PRINTING TELEGRAPHY Another way of looking at the ¢ondition is that the two brush arms are revolving at ex- actly the same speed, but the receiving arm stays a little behind the trahsmitting arn, the distance behind depending upon the cur- rent lag. This last described system constitutes the Morkrum System of Printing Telegraphy reduced to its simplest form. The scheme includes the essential features of the Morkrum distributors. (These are so called because they take the five character elements of position, which are found on the tape, distribute them as impulses or elements of time, and then, at the receiving station, re- transform the elements back into those of po- sition, that is, relay positions.) This dis- tributing apparatus, together with the tape perforator and automatic printer, makes up the commercial Morkrum System. ES YHTAMDETET DUITUIAZG TO METeYe MUSXAOM ANT et moftrbaod edt ts antadool to ysw tedtomA -xe te goiviover ots emre decid ows odd tadt mre sofvisost edt ted ,fseqa omse sit yitos ,urs enttivimatett odd iotded slitil ses eyste -ire edt coqy antimeqeb butded sonstelh oft nel trot moteye hediroseb tesl atdT opt tated to metaye mrraxoM ont) coturtitenos ed? .orot teelfqmie ett ot boouber ydostzefe? edt to eexrstset [etinesre eft aebrulont emodoe, heliso oe ets evenT) .erotudiaterh suxdrolf ginemele tretostsdo evit sat svet yort. sevsood ,eqet edt mo Bosot ere. dotdw ,mottituog to to avaemele to seetraqmt es medt etudtttalh . ~et ,mottete saiviesoot eft tea ,cedt ime ,omtt -og to eeodt otnt atosd. etremefe edt mrotenatt. -eth eid? (.anottteeq yelor ,eb sed? ,cottte eqat edt dtiw ratheans eestetsqqs anitedizt. qe sexen ,tedaing oltsnoisa bas rotetotteq — emetearcé mortroM [stetemmos edt THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY With this preliminary survey of the plan, we are ready to take up a de- tailed description of the commercial system. There are a number of different types, dif- fering in the minor details, but the one de- seribed in the following pages is the one commonly used on commercial duplex telegraph lines. 34 YHTAAOSIAT OUITWIAT LO MATEYe MUSSAOM FHT Yevive Yrenimifstq add Ati -96 8 oss exet of Theer eta ow ,melq eft to -meteve [stotemmoo edt to mottqixroveh bolfist 2%ib ,eeqyut tnerettth to tedmsmt s srs evedT -eb oso oft tud ,efieteb tontm oft at anttet eto oft et sexsq saetwolfot ont af bediroe dqetsefét xelquh fetotommos mo hoes yinomes “P'S Seenel ” i 35 THE MORKRUM SYSTEM OF PRINTING THLEGRAPHY Part II - Tape, Code, and Perforator. THE TAPE. As was said before, the message to be transmitted by the Morkrum System of Printing Telegraphy is first punch- ed onto a paper tape, the number and arrange- ment of punched holes depending upon the let- ter or character which the holes represent. Samples of the tape are shown below. SHIFT @ E RD I SN PMR, EN Fh Le D Te ta ZR SS Fe 42 B The holes for any one letter or character are arrenged in a row across the tape, with the proper blank or unpunched spac- pha Lei ber i ae a A ! Bae HA TRS ee SORA te, Ee in) ees £ ra , ems £9 0) 09 ‘ y * YETAAOMIAT DLITUIAT TO METAYS MUSHHOM THT stotstotrel bas .,ebod ,eqsT - II tref ,ototed bise asw eA .ETAT AAT. . TS day mrritoM edd yd bottinenart ed ot eseaeem edt -doanq terit et ydqergefe? anitatr1t to meteye ~opierts brs tedmor edt ,eqst reqsq 6 otme he | -tof edt moqs anthaeqeh esfod betonuq to taom * stoeverqer eefod edt dotdw tetoartsds to, rot pee | iid en mote ers eqet oft to eelqmet ie 36 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY es between holes. The rows are separated a distance of about one-tenth of an inch, this being sufficient to produce clear distinction between successive letters. Notice that the rows of holes are not exactly perpendiculer to the length of the tape, but that they Slant backward a little. The reason for this Slant will be explained in connection with the transmitting distributor. Besides the holes used in combinations to represent letters, a con-. tinuous row of holes runs the full length of the prepared or pundhed tape. Theses holes are used in feeding the tape through the ap- paratus. The teeth of » small spur wheel en- gage the holes, so that the tape is draw a- long as the wheel revolves. This system of feeding affords a positive and definite tape movement; the tape cannot slip without the et ie me ee. Be YETAROMITT PUITHIAT TO METCYS MUSAHOM SHT s betatsqse eta ewot edt .asfor meewted eo ettit dont mae to dtnet-ero tvods to sonsterh nottontteth tsefs ssrborg ot tastofitsue anted edt tent oottol .erettel evtaassove moewiod telcotbaeqie, ¢ltosxe tom ste eoelod to ewot yedt tedt ted .scaet edd to dtamel edt of etd? rot nogser edT .oftdil s Stawfosd taale dtiw mottoenmos at bemtsfqre ed [ftw trate »votudizxters setitimenert edt mf hoes eolond edt asbiteod .-f09 # ,erettel taoeerqar ot anoitsaidmos dtamel fist edd anor aeLorl to wor evoumit eelod esred? .eqet bedhasq to bexeqorg ext to -qe eft detromt eqat edt gctboet at beam ers -te foedw roqe [feme 2 to dteet edT -estorag -s mwarb et eqst oft tedt 08 eotod ‘edt 9389. es) motene etat seevloves. feedw eft as gaol oaat othnttes boa evitteog 8 ebrotte Batbeot fit, PRON Em aC, Sonne: eat, ot: RCE THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY feed holes being torn out. If such trouble occurs, it is at once noticed by the opera- tor and can be remedied. THE CODE. The perforations f follow the plan of the five-unit code, which is given on the sample of tape, p.35. This is called a five-unit code because for each letter or character, there is a total of five intervals, either holes or blanks; "blank" is used for want of a better term, and denotes évery location where no hole is punched. The intervals or elements are numbered for refer- ence 1, 2, 3, 4, and 5, across the tape. The five elements allow of thirty-one combinations; hence, thirty-one characters are available. By the use of a shift, similer to a typewriter shift, thiry-one new meanings may be assigned to the combinations, so that a total of six- ty-two characters or signals are available. 37 4225 2 ao PN 0 Se eae Vay) 7" cn vé YHIAAPAINT YPULTHIEI TO MaTeye MUSAGOM FHT {dsort fovea tI tro mrot. gated eefod feet -steqo edt yd heottom esno ts ef ti: ,ertmeo0 -bethemor od aso bre tot t emottarotreq oft .8000 AAT detdw ,ebos tinu-evit edt to msfq sdt wolflot aid? .28.q ,eqst to elqmse odt mo movig at fose tot oenssoed shoo tins-evit s belfse af evtt to Latot s at eredt. ,xetostado to.tetiel af notre td yeunsld to eefed redtte ,elevretat eetonebh bas ,mret tretted a to tasw tot bees at eiT. .bedonuq et ofod om ototw noftsool ytevs) -tetet tot bevedmrc eis atwemele 19 alevrotat ed? .egat odt agotos (@ Bas ,.4.48 8). £ some janoktsaidmoo eme-ytitdt to wolfe elnemole evit sefdslteave ers eretostads smo+yiridd , eomed totixrwegyt s’ot ralimte ,tiide es to sen edt yf bedtgtees ed yan esalnecom wen emo-yridd ,ttide -xfe to Ietot es tadt os ,enottsnidmoo edt ot -oldsitsyvs ers afsngie to sistosrado owt-yi - THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY Besides the actual charac- ters which are to be transmitted and print- ed at the receving station, the code algo includes several operating signals, which govern certain functions of the printer a- side from its regular printing movements. These signals are: space, carriage return, lining, shift, and rub-out. The space sig- nal causes a space to be left between suc- cessive words of the printed messace. The carriage return is used when a new printed line is to be started. The lining signal causes the printer to turn up a new line, just as is done in the operation of a type- writer. The shift signal causes shift char- acters to be printed instead of the normal characters; the printing of the normal char- acters is restored by the space or the car- riage return signal. The rub-out is used 38 YHTAROSIET OUITUIALT TO META Ye MUSUIOM aaT -oateulo L[estoe oft aeebteod -tattq has bettimenars od ot ote foftdw atet oels eboo odd ,cobtste gatveoer odt ta he dotdw ,elenstea setisreqo [ateves eobsfont -8 totairg et. to enoktonst aisitos arevog -atnomevrom gattateq tafsser ett wort obte : stutter ensinrmo ,soasqe cers aleanate seed? -gte sesqe eT .tuo-dort Sas ,ttide ,»sototl -ore moewted ttef od ot onmtet ie absien fen ed? ,egsacem betaitq oft to ebrow evisseo hetaitq wen & cenw bees af atuter sgsivsso fergte gatetl eff .betrate od ot eb ombt in . ,emkl wen sa qe mot ot. totairg eft mosses + a) oeqyt-s: tor ROLMATATO edt mb enoh at as tent | | -tedo titde asaueo Langte ‘Wide ed? teem io (¢ Lemrom ect to, besteqk betaiyg od: ot anotee ree a tnefe, Lene ost, ett 20, anttabeg ot, am a THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY 39 when a mistake has been made in perforating the tape. The tape is run through the perforator again, and the erroneous letters are punched out. Note that the rub-out combination of hole is the only one comprising all five intervals; hence, any other character contains fewer hole and can be punched out. When the printer re- ceives the rub-out signal, it remains inopera- tive or "marks time” until a different sienel is received; the printer then performs its us- ual functions, just as it did before the rub- out signal was received. THE PERFORATOR. The tape is punched by means of a keyboard perforator. The general performance of the machine is as follows: The actual punching of the tape is done by a row of six pin punches which face a die; the tape passes between the punches and the die. Five of the punches are for the five S s, YHTAAPRIR?T PLITHIAL {TO METEY2 MUSAAOM EAT eit satterotreq ot sbsm meed sant odatetm 2 coeriw sotstotireg edt daugorit ocr af oqst edT .oqst boedoasq ots etottel exsosnorre oft bas ,aisaus eeLlod to mottsatdmos two-dur edt Tadd otoll .ts0 seleviotnk evit [fs antettqmos emo yimo edt et ,20fod tewet entsinoo tetoasredo tedto ya’ ,soned -et tetmixng ont med% stwo fofenng of mao bia ~stoqomt amisner di .,fergte tyvo-dst edt eevteos {srgte tastesttib e [tian "omttd axlrean”" ro evit -en edi enrotreq nedt retnira edt yhevisset ef -doxr odt ototed S5rb tf es taut ,emottonst Lar ebevieosr esw L[eagta Tso eit eget et? ,fOTAROTAET BHT stotatotres hSrsodyet s to ensem yd herfonsg as at ontdoam eft to eomamrotreq [steaes edT ef ogst sdt to gnidonsq Isetoe edT vewolLlot s eset dotdw sedonng atq xte to wor ‘ vd ectob bra esdonugq eft coowlsd eosesg eget edt jofb evit oft rot exs eedomnq edt to evil sath odd es esyu ik: * : tie 40 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY code holes, whereas the sixth is for the feed holes. An electro-magnetic hammer forc- es the punches through the tape; on the back or return stroke of the hammer, the tape is advanced one feed hole, so that a fresh sec- tion is ready to receive the next series of perforations. Different combinations of holes are selected for the different characters by a selective mechanism worked from the key- board. This mechanism operates as follows: Between the hammer-head and the punch pins exists a small clearance, in and out of which five rods or punch levers slide independent- ly. One punch lever is provided for each of the five code punches, but none is provided for the feed punch. When certain holes are to be punched, the corresponding punch levers are left between the hammer head and punches, filling up the clearance. On the forward stroke Ob YHIAHOTIZT OMITUIAT TO MRTEYe WIARAOM FHT eft tot et dixte edt esstedw ,selod oboo -srot otmed ottemasm-ortosfe aA .aeLlod’ beet Noed odt mo pedst edt davouwlt eerdomeq edt es et east odt ,temmed edit to exotte orrtet to -96e deett « tedt o8 afoul best emo BSesnsvbs to settee txen oft eviteost of yhset ef nott aefod to enottsatdmos tasetettric senordsrotreg yd erotoarsds drorettib edd tot hotberee ove Lyed oft movt bettow meinedoem svttesrea 8 tewolfot a8 eetaredo metnedtoom etd? .htacd oe «s eat douva oct ae basd-tommed oft moowted dotdw to two bas mt ,soneteeld [lama s ateaixe -trebteqobat obife atevel deovg to abot evit to dese tot hebivowq at revel Sousa end ee Bebivotc et omon tud podonng ae et ott 3 eee ‘ore eofodt atetrtso mod sons Boot eft tot 3 a erevel donug acfBrogesrtos éat ,Setfoanq ed of , eotomng baa feed remmect edt aeewled ster basis eforte brewtot edd m0 Lesneteefo bail eid went 41 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY of the hammer, the pins are pushed through the paper. If a hole is not to be punched, the punch lever corresponding to that hole is withdrawn from the clearance between the hammer and punches; then, on the forward stroke, the hammer enters the clearance, but not far enough to strike the pin. Hence, no hole is punched by that particular pin. The feed holes are always punched; the selec- tive mechanism has no contol over the pin which punches the feed holes. The rods or punch levers are controlled through a series of levers from a keyboard, similar to that of an ordinary typewriter. The keyboard also automatically control the electro-magnetic hammer, With the idea of the general functions of the perforator in mind, we can now take up a discussion of the machine in its ie PEE eo fs YHTAROAIAT DUITHIAG FO MATEYe MUAAHOM TAT devouwdt Sbodewa ote eaie sft .,tommadt eft to bedonug ed ot tom st olfod e tI iseqsq edt ofod tedt ot antbooceet1ros revel donuq odt eft neswisd sonerselo oft mort mwstidtinv et Sterrot edd mo ,nodt :esdouug fae tommsd ,somerssf[o edt eretme remmead edt ,eforte ,e0meH .mitgq edd exitte ot davone rst ton tud iq tefsolireag.tadt yd bedeasq st efod on -oolfee edt ;hedonsg eyswie ere sefod beet odT aig edt tsvo Lotion om ead me imedo om evit 10 ehor off .eslod hest odd eedomuq dotdw esiree. 8 dasordit Belfottaon ere etevel dong ted? ot telimte ,Srsodyex a mott erevel to cele breodyex en. .retirweqyt yrantizo as te ettengsm-orteele edt Lortaes ylfeottanciss tate it eT emmedt Leveneg ent to sebt edt MtkW 0 yey neo ew ,batm mt roterotieq edt to poston i) ett mt eidoam oft To eakone gets 8 Waitara 3 ron THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY practical form. In this entire discussion, rough sketches will be used to show the gen- eral construction of the parts, but these sketches are not intended to represent the apparatus in detail; the accompanying photo- graphs of the machine show the details of construction. GENERAL LAYOUT. The perfora- tor consists of a hollow cast iron base, on the top of which are located the hammer and punch mechanisms and the tape reel. The key- board overhangs the front of the base. Some of the connecting levers between the keyboard and punch pins are inside the base, whereas some are on top. Fig. 7 shows a top veiw of the perforator; the different parts are iden- tified in the sketch. THE FUNCH PINS. At the lower left-hand corner of the base are the punch 42 ss YHIAHORIAT DEITHIAI AO Mateye MUAAHOM aT -toteavoeth etitas etdt al. .mrot Leottoarg -~neg edt wode ot hDsev ed [fitw eedotete. darort eaedt tod ,etreq edt to ootteutdedos [arte eit tasserqsr ot hebrotnat ton ers eeslotede -otodg goiynsqroces eft :{isteh at extstsqqs to aftsteb edt, wode satdosm edt to efgerg »coftonrtedos -stoiteg edT .TUOYAL TASm URS ae} mo ,9aed moti teso wolfod s to etetenos zo¢ bas tremmed edt Setsool ets. dotdw to got. edd -you ofl .[ee% oqat edt bas, enalasdoom Hoos emoe .oasd edt to taoxrt edt agasditevo hisod Srsodyoxt edt seewied erovel grttoeinos..edt to esotodw ,csasd eft ebient ers eatg donug bas to whev, got s awode ¥ .gtt .got mo erg moe -mebt sis satis tooerettts edt jrote rot req oat » 9 -etotete eft at betttt tewol oth th, .2UTT BOUOE ABB oy won che eee: Honig, edd. ets. oasd, nity shcndbase boedetteL 4 43 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY pins and die. The punches are of steel, about one-tenth inch in diameter by one and one- fourth inches long. There are five of such pins for the tape contact holes, and an ad- ditional smaller pin for the feed holes. All six pins slide back and forth in guide holes bored through the face of a small block. The idea is illustrated by Fig. 8, where B denotes the guide block. The block is[_-shaped, and across the open face extends a cover plate, HE, also bored with guide holes for the pins. The die, D, lays over this cover plate. The two are channelled out slightly so that the tape can be drawn along between them. The pins ordinarily project behibd the back face of the block, and also extend, at their op- posite ends, nearly through the end plate, E; they do not, however, extend into the tape channel. The hammer strikes the projecting eh YHIAADHITT QUMITAIAT TO METCYe MUASHOM HHT trods .Leets to evs eedoonq ofT woth Sas ent -ero bas emo yd rtetemeafh at dont ditnet-oeno foxa to evit ets ered? .smol eodont dirsot -5a ms bas ,aefod fordabe eget edt rot eat [LAiseelod boot edt tot miq telfeme L[anottrs eefod ebies mt dtrot Bas aosd obife entq xfa edit .woofd f[feme s to goxt odt dgrorit hetod astomeb G& etedw .8 art yd botertes{[t et sebt bas’ ,beqede- jet xoold ed? .footd ebtag edt ,eteala "ovoo 2 Bbaetxe eset meqo edt eeotros -anig edd tot gefod situg dit berod oefs ,f edT .6telg tevoo efdt revo eysl .c¢ .9tb ext edt tedt of yltdatla tso bolfLennsdos e212 owt ‘edT .modt asowted aoole swath of neo eqat eset dosd edt Sdided toetota ylitenthro emt «go ttedt ts ,baotxe cafe bas ,foold edt to, otela fre edt davon} yfrsen ,ebae dtteod eqst at? otat bratxs ,tevewod ,tom ob yedt 32% aatioetor odt eoxttte roomed od? .feamede aa. eae THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY ends of the pins, and drives the pins across the channel into suitable recesses in the die; if the tape is in place between the die and end plate, it is of course punched. The punch ends of the pins are slightly hollow-ground so as to give better cutting edges. The method of returning the pins to their original positions, on the back stroke of the hammer, is also indicated in Fig. 8. The feed-hole pin, F, is rigidly at- tached to af -shaped crosshead, C, which slides back and forth in the guide block; the crosshead is normally held at the rear of the guide block by the spring, S. The for- ward stroke of the crosshead is limited by its lug (the stem of the "1") striking the end plate, E. The croddhead is also bored with holes for the punch pins, but the fit between the crosshead and pins is so loose 44 AL YHUAROAIAT: MMITMICL TO METEYS MUSAZOM ANT eeotos aniq ont eevith bre ,emtq. edt to ebro ;9L5 eft at eeeecost sldetinog otnat Iennsento oft has efb ett isowted seefd mt at sqet oAtT TE domuq off .bedoanq oersoo to af ti ,etslq bao Brsorg-wollod yitdatle ete antgq edt to ebas. -cogbe anifive tetted evig ot as 08 ed? gartarstexr to bodtem ext dosd edit mo ,exottieaoq Leniygiro tredt ot anmiq’ at Betsofiat oels st ,temmed edt to sdorta’ -ts yibtatt et .& ,atq efond-beet ed? .8 ait ffotdw .0 .bsedeeoto beqede-~ 8 ot betoat “ytooltd ebbing edd ot dtrot Sas dosd eaebile rast oft ts bled qflemrom et Ssentehoto oft -tot of? .2 ,antrtqe edt yd Moold ebtusa sft to wd Betimtr at baadecors eit to eslovte brew edt gatutxvte ("I" edd to mote ont) ‘anf att Betod oafe at beedtibors ef? .f ,etesla bas Fit edd stud ,ento devrg eft tot eoefot Atiw geool oa Bt enty Bae heedesoto ett asewted hh SPS rare gel BS 1 ee NRE 45 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY that the crosshead slides forward freely, without pulling any of the pins along with it. Each of the five pins is fitted with a small collar, which rests against the twck face of the crosshead. The crosshead ordin- arily bears against these collars, so that the pins are held in their extreme back po- sistion clear of the tape. In the operation of the ar- rangement, after the crosshead has started on its forward stroke, any of the pins can follow, in case they too have been struck by the hammer. The crosshead stays ahead of the pins until the end of the stroke, and the pins go through a punching movement the same as though the crosshead were not pre- sent.On the back stroke, however, the cross- head strikes the collars on the pins and carries all the pins back to their original os YHIARDELST PUITUIAL FO METEYS MUARHOM AHT .YLeert brewiot goebife Ssenleeoros efit tadt dtiw anoles entq eft to yas amifl(uq. truodttw 8 Atiw hottit et eatq evitt edt to dosi .tt wo sf odd tanteses eteert dotdw ,relloo [lame -aibxo beedegoto efT .fsedesors edt to esst Jadt of ,atalf[oo saedt temiszs ataed yLite -og Zoed omertxe x tedt ot Bled ors entg ont -eqsy edt to reefo mottete -18 eft to mottareqo edt al Hhetiste ead Ssedesoro. edt totts ,trome'gcet meg ant edt to yre .exorte brawrot ett mo dovite need eved oot yedt caso at ,wollet to beeds.eyste bsedezoro edl,.commsd-edt.yd Sas eodotte ect to bne edd [ives anigq edt edt tmemovom,guidonng s dgsormt og aentq edt -9tq tom etew bsedesoto edt dguodd as omse “spore edd .tevewod ,giorte aosd odt a0, tn08 Snes acta edt mo areifloo edt eeiirte beed featgtto tled? of toad eatq edt [fs aetriso - | : , 46 THE MORKRUM SYSTEM OF PRINTING TEIRGRAPHY positions. A feature which should be noticed here is that at the end of the forward stroke, the pin collars strike the crosshead, and their travel is thereby limited; otherwise, the pins would drive into the die and soon loose their cutting edges. The method of starting the crosshead on its forward stroke is also ap- parent from Fig. 8. It will be remembered that the five contact-hole pins are not struck directly by the hammer, but instead, small interference rods are inserted between the hammer and the pins, so that the rods are struck by the hammer. A feed hole, on the o- ther hand, must be punched at every stroke of the hammer, and hence no punch lever is provided for the feed pin. Instead, this pin projects beyond the others a distance slight- ly in excess of the thickness of a punch lev- ob YHCAADEILT DUITMMIAT TO MeTeYe MUMAOM TA? heoiton ed Si{yode do tdw esriteset A semoftieog ,otorte hrewrot edt to Bas odt ts tad? at erod ttedt Bas ,bsedesoro odd otttte arsf[Lloo mig odt eatg edt ,setwredto ;betimil yderedd er Lovett ttedt seool mooe baa ef5 edt otmit evith bisow . -2ogbe gaitiso edt enitvate to Bbodtem sdT' -qs oelfs at etorte Sreawrot ati mo bsedeasots heredmemet od £[fiw tf .8 .gtt mort tneteq fourte tom srs entq eLod-tostmoe evit edd. tadt If{eme ,hbestent sud .remmed edit yd yitoorth eit oasewhled betreent srs ebor sonsretretat ets ebot edt tedt oe ,satq ond Sas cremmed -o eft mo {efod best A .rommed edt yd aourte exorte yrove ts bedonuq ed tenm bead redt et revel deonvq om eonmed bae ,tommed ,odt to tigq etdt ,bsetenl .atq hset atid tot Sshtvorg -trigife senateth s etedto edd broyed -etoetorq -refl domuq s to esemsoidt edt to seeoxe at yl. 47 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY er. Therefore, the feed pin is struck by the hammer before any of the punch levers, so that the feed pin and crosshead lead the other pins throughout the stroke. It is ap- parent that with this method, the proper movement of the pins is not interfered with by the crosshead. THE HAMMER. The hammer mag- net consists of two solenoids, designed for 110 volts, direct current. The solenoids are placed horizontally at some distance behind the punch pins and in line with them. The arrangement is clear from Fig. 7. The two coils are supported from the base by 4 brack- et, which is attached to those ends of the Goils adjacent to the punch pins. The solen- oids are fitted with movable cores or plung- ers, which slide in and out of the rear ends of the coils. A yoke connects the cores, and Th YETAROTIET DUITHISY GO. Maeve WURAAOe ERT eft yd Momrte ef miq) best edd YototeredT .19 . oB! ,etevel donug eft to yaa stoted roamed edt haa! hsedesots bas atq beet odd tedt -qz at tI ,exotte odd tuodasordt entg tredto teqorg oft .bodtem efdd ditw stadt Jasteg dttw berettetat tom st satq odd to tremevom » .Beedeeoto ett yd -gam-tommed eT. .HEMMAR: ART: TOt.Bomgtesh ,sbifonelLoe owt to etetanoos ter ets ebtonefloe od? stmstiso gosrih ,atfov Off baitded somaterh omoe $s yifatadstromd Soosl¢ edt ..medt dtiw eatl at baa extq dontq sdf owt of? .V.2hT mort tselo at tasmegratta -toatd « yd saad edd mort botroyquae eta eftoo eit. te shas oa0dt ot hedosits et dotdw te -seloa edd .amtq donag edt ot tnenshbe @: : : -gariq to eetoo sldsvom détw bettit. en shee, seamen feo nahn mk ehte: SPOR SF 4 bos ,eeroe edt atsennoo exoy A. sltoovedt to" . 48 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY from the center of this yoke, = plunger rod goes forward between the solendids, through a guide hole in the bracket, and terminates in a round-headed nut, N,. A hammer spring, acting against the magnet, normally keeps the cores drawn partially out of the coils and the plunger rod in its extreme back po- sition. When the coils are energized, the cores are drawn into the coils, and the plun- ger rod thrusts forward toward the punch pins. The hammer solenoids are controlled automatically from the keyboard. The hammer itself is a hori- zontal steel lever, pivoted at A (see Fig. 7), and extends into the clearance between the end of the plunger rod and the punch pins. Thus, when the plunger rod comes forward, it thrusts the hammer on ahead of itself. The construction of the ham- Ob YHLAHOALTET DULTUIAT TO METeYe MUSAHOM HHT hor tegmutaq s ,ovoy etht to retas0 ent mort davorts yebtonafoe edt seewted brawict seog eetentarre? bus ,tefoard eft xt efod ehiva’s ,adince vemmed A.W , tum bebsed-hnsot e@ mt eqeer yilamron , tenga odd tencisas uitios aftoo edd to tuo ylisttisg twerb dstoo edt -og Hosd emexrtxe ett at hor tegneiq odd bas ext ,bostarere ers effoo oft sodY .aottte | -onlq edt bas ,efioo ‘edt otth mwath sts eerde ne doasq odd Brawot Brawrot aveutdd hor res 3 bellortice ere eblodelod tenkied ed? sant -5xaodyex edt mort yLlsottamotys Pie es: ~tiod @ et tfowt! tommed ed? © 9° * | ae o( .Qlt cee) A te botoviq ,revel Leote Istnos : ‘eit meowted sorersefo ent otmt ehmetxe Bae “lemtq donsq odt ae bot tosasfa edt Yo bme | )) .brawrot evemos Bor regax tg att aedw esd? ( \Sfeadt to beeds no remax odd eteotdt $2 oe ‘smad edd to nottowttenos edt) 8 te tig 49 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY mer is shown in Fig. 9. As indicated, the hammer is channelled out along its length. The channel faces the punch pins. In line with the pins is cut the rectangular notch, B (see Figs. 7 and 9). When the end of the hammer is pushed forward by the plunger rod, the ends of the punch pins enter the notch, B, The channel and notch furnish the clear- ance, before referred to, between the punch pins and hammer. Note that the bearing at A, upon which the hammer is pivoted, is offset from the center-line, so that the bearing stud is well clear of the middle of the chan- nel. " THE PUNCH LEVERS. The five interference pins or punch levers, which slide in and out of the clearance between the ham- mer and the punch pins, are merely square steel rods; they move lengthways of the hammer through a") ' Ve) ore! <> a ae eh YHIAADEIAT DUITHIAG TO MATCYa MUAAZOM HRT edt .fetsotint eh .& «ett of awode ef rem Ateool ath gaolea tuo bellomnsdo ei temmad entt al .antq dogsagq edt esoet Lormedo oT doton taleanstosr sft two ef ent ot dtiw eft to bre edt mod! .(2 bas Y .egtt ese) & ,bor tegaulg edt yd brewrot bedeng al remmed dotom edd tetne antgq doasq oft To ebme ont -tsefo edt detotyt dotom bas fonneado edit .& sonugq oft meowted ,ot bertetet stoted , eons A te guitsed oft tedt eto jrommat bas eniq dogito ef ,betoviq ef temmed edt dotdw nogr antteed ofirtedd of ,enti-retaso edt mort | -nado eft to efhbim edt to tsefe Liew ab bute =~ e aera: 7 fer He evit ef? .etiVal HO“UT HHT efile dotdw ,erevel doauq to amt eonetetrotat. -med ont noowtod eonstselo edt to two Bas, at Teste erempe:xforem ets ,emiq omg odt bre tom dgrotdd renamed edd to eyewdieael evom yedt jebot ~ 50 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the channel. They are arranged in a vertical row or pile, so that each one is in the hori- zontal plane of a punch pin. The levers are numbered from 1 at the bottom to 5 at the top, corresponding to the same numbers of the code elements. The punch levers extend just far enough along the channel that their ends cross the notch in the channel, and thereby fill up the clearance space at the tack of the pins. However, each lever may be withdrawn from the channel for about half an inch; this movement is sufficient to re-establish clearance. SELECTIVE MECHANISM. The meth- od of moving the punch levers from the key- board is illustrated in the isometric sketch of Fig. 10; this sketch, for simplicity, shows the complete links for only one punch lever, and shows only one key. Hach key is the ter- minal of a long arm, K, the back end of which O38 YUTAMDAINT AMITUIAT LO Maree MUAAOM ABT feotsirev s af besnstre ots rod? -fomisdo edt ~frod.oft mt et ono, dose tedt oe ,eltq.1o wor ete erovel off .miq donuq s to onelq Isitnos got edt ters ot mottod edt te £ mort botedmia eboo edt to eredgum omae odt ot anibmoqesetios _ st test baotxe exovel donsq edt .etmomefe 2B0TD abtre wiodd tedt Lonnedo oft gaols devote qu.[fftt yderedd bas ,fennedo edt of doton oft -egtq ent to aoa edt. ts .cosqe eouatsslo edt edd siott, owerbdtiw ed yem revel, tose . TevewoH taemevom etdt jdont os iled twods tot Lonnsido -eoretselo delidetas-et of daoototitue ef -ddem eiT .MeIMAHORM SVITOMIAE . fo -yor odd sort exevel donsq eft aatvom to bo dotese otutemoat edd mt beterteu[{t et braod awode ,qtiotlamie tot .dotexe, atdhj;0L sett 20 emae ~tmomevom qool hrs stelqmoo edt mwode et LL .ght aly, meets | emoe to amoisqeoxe edd dtiw metasdoem avitoelee tTtel ere dotdy etevel fora eyed brsodyed eft to -taen to hodtem sit .dotefe sdt vitiqate ot tro edt to tmomegasits edt bas aqool xte edt gat fotede eft .yf{stosqes betom ed bivorle axneto [led Rat vow fore to £ chy: exogalt: fsvsvee oft awode osfe . faa ,brewnwob tatoq etegalh oseXt ssotttes Tov - -aetqeb est ,eonedt :2aqool edt to Ofr0, HO: eteon, soe, Latevea asaeenyed ufesoonst fente: yet! to ee r farevee ewsrhdttw |, omtt omae: oft te: bee ay sa : dove efLortnoo, yet sy, mottos eld yh s erevel 7 Da 53 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY punch levers as will cause the proper holes to be punched in the tape. The hammer control is indi- cated in the same figure. In addition to the five bell cranks, there is a sixth lever mounted with them and similarly controlled. This lever is the top one of the bell crank group, and is operated from the outside loop. The top lever has no long arm extending to a punch lever, but instead, consists of a single arm, identical with the short arms of the bell eranks. This arm controls the hammer magnet through the series contact shown. One point of the contact is stationary, whereas the oth- er is carried by the lever just mentioned. The contact is normally open, but when the arm is moved forward, by a depression of the front loop, the contact closes and connects the solenoids to the source of current sup- YHTAMDAIAT DAITMIAL TO METeYe MUSAAOM FHT aefok tecorq eft eeseo [ftw es arevel donnug -ogst eft at bedonug ed of ~Ehat at Lortaos trommad ait edt ot mobtifis aI .statt omee edt mt betsoe vtevol dixta es at eredt ,edimeto [fed oevit eSellortaos yfralimts bas medt dttw betarvom Aneto [fod eft to exo got oft et revel etdAT -qool ebtatro edt mort betsteqo at Bae ,quorty 8 ot antinetxe mrs srof om ead tovel qot eT efgste s te etetenoo ,fhsetent tud ,revel donuq {fed oft to amrs trode odt dtiw Isottmwedt ,mrs temgsm temned edt eLfortmoo mra eidT .etinsto tatog enO .mvwote tostnoo sasirea edt davordt -dto edt essredw ,yrscottate at tostaon eit to eSemotinem test revel edt yd Betttras et te eft monty ted ,neqo yflamton et tostnoo ed? edt to moftasetqeS s yd ,fSreawrot Bevom ef mrs etosanos Bas esects tostmoo eft ,qoof taort -que taertso to servoe edt ot ebtomefos edt THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY ply. The contact is adjusted to close just after the punch levers have been withdrawn by the bell cranks. As for the location and mount- ing of the link mechanism on the machine, the bell cranks and contact are situated an the top of the base, as indicated in Fig. 7, where- as the loops and keylevers are inside the hol- low base of the machine; the levers F of Fig. 10, connecting the loops and bell cranks, ex- tend upward through slots of the grid, G, as indiested in Fig. 7. The mounting of the bell cranks on the vertical studs is also apparent from Fig. 7. The method of suspending the loops and key levers in the base is illustrat- ed in Fig. 12, which is a veiw upwards at the bottom of the machine. The six free ends of the two sides of the loops are mounted in the 54 YEIAAOAIRT DALTHIAT TO METCYe MUARAOM HHT test asofo ot betesths et tostaoo edT .yla awethditw seed evad erevel donsq edt retts -aineto [fed edd yd -iasom Baa aotssoof edt rot #2 edt ,eatdosm edd no matnadoem eat{ oct to amt edt om betsutte ets tostmoo has exnete {Led -otedw ,." .nti at betsotbat es ,seaad eft to got -fod edt ehbtent ete erevelyed bae scoot edt as aft to % erevsl odd jeatdosm eit to casd wolf -xe ,avesro [fed has eqool edt anttoennoo ,OL es .© ,bixvg aid to stole danotdt Srawgs bast {fed edt to gattavom of? .¥ .att at botaoliat tastaggs oasis at ebsta [sottrev edt ao etnats eV. .gtt mort edd gatbhneqese to hodtem dT -tettas([l?t st eesd odt at atevel yet bas sqool ed? ta shtawqy wrev a ef dotdw ,&f .@tt at be to alae sett xte ed? .entdoam oft to mottod edt mt hetavom ets aqoot edd to eohts ows odd pf A oe ee a fae! 3 * 4 a4 wy THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY two bearings as shown. Washers or spacers are pleced between adjacent straps in order that there shall be no interference between them. The loops are held up snugly against their backstop on the under side of the base by return springs. The idea is eleear from Fig. 13, and needs little comment. The rod, R, of Fig. 13, runs the full length of the loops. This spring support allows the front of the loop to be pushed down by a key lever, but immediately returns the lever to its normal position when the pressure is released. The mounting of the key levers is similar to that of the loops, and is shown in Fig. 12. The back ends of all the levers are strung loosely on a shaft, 8; the levers are kept separated on the shafts by spacers. The key levers have spring returns, similar to those of the loops. All springs, both of 55 ou Cs YHCATOLINT OUTTAIAI FO MATSYS MUAAHOM ANT eTs ateosqe to ersdesW .mwode es eanttsed ovt seit teSro at agarte tnesestis moewted beoslq emendt moowted sonetetretar om ed [fade eredt tteit tveateas ylaune qu bfed ere eqool eft qd eead edt to eshte tebas ods mo qotexosd est? mort reafo et sebt ofT .eantiqe arustet to ,f ,hor edT .tnemmoo s{ttiil aboom bas ,éf -2eqool edt to dtanel [fut eft env cL att edd to taott edt ewolfa troqaze aairce ald? txud ,tovef yout a yd mwoh bedsersq ed of qool fenrrom ett ot tevef odt eaanruetor yiststbhemnt | eDbosseler st orteeetq sdt aodw nottteog atevel yet edt to sattarom eT ) mwode at bas ,aqool adt to tsdt ot tafiimte at etevel edt {fe to aime doad ofT .SI .utt at arevel edt ;& ,ttede s mo y{ssool anurte ets ~eteosqe yd eftedea edt mo hetersqes tqex ors ‘siimte ,anruter anitxgea evad erovel yex siT to diod ,sgaitqs [fA .eqool edt to saodt ot THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the loops and key levers, are anchored to the rod, R, of Fig. 13. THE KEYBOARD. The key levers terminate at the front of the machine, have key buttons attached to the front ends, and thereby form the keyboard, The plen of the keyboard is cleer from Fig. 7. In a general way, it follows the plan of the standard typewriter keyboard, but as only upper case letters are used in telegraphic work, addi- tional characters are supplied instead of the two separate styles of letters. Notice that besides the actual printing characters, the keys include the operating signals, such as carriage return (CARRET), lining, and oth- ers. THE TAPE FEED. The method of feeding the tape may be seen in Fig. 7. The tape reel is normally supported horizontally on the top of the base to the right of the 56 ad YHTAROEIRT OMITAINA TO MATSYe MUSAHOM FHT ot betodons ete ,atevel vei Bas eqoolt edt -8f£ .2tt to .f , bot edt etovel yew ofT .CHAOSYaA HT eved ,emtdosam oft to tnortt oft ts etsainret bos ,eise tnootrt edt ot bedostts anotind yox edt to asfgq eiT .fraecdyei sft mrot yderedt feteneg a ml .S .att mort S sett mort rsefo at ,temgem tro-tuo bas edt dtiw seltrea at et tostnoo revel qote edT -a betoonnoo ere ovt oft bas ,tonnem tvo-tso eYrotiad [seol eft eeoto pf THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY THE RECEIVER CIRCUITS. The receiver circuits are shown, somewhat simpli- fied, in Fig. 26. The path of the impulse from line to ground is through one coil of the main line relay, through the milammeter, through the other coil of the main line re- lay, and through the artificial line to ground at G', The milammeter is connected in series with the main line relay, so that a more ac- curate idea of the strength of the incoming line impulses may be obtained than would be furnished by the movement of the main line relay armature. The artificial line is merely an adjustable resistance and capacity in par- allel, connected between the main line relay and ground. The function of the artificial line will be taken up during the discussion of the polar duplex. The tongue of the main line fff YATAROEIAT DAITHIS EO MATEYS MUAAROM EAT ent ET IVORTO AHEVIGOEA FHT -fiqnts vedwemoe ,mwode ere etivorto tevtecet eefleqmt oft to die, eAfT dS .nlt mt deft to [too ono dasrordt at Bavora ot entl mort eTetemmelin edt deavord? ,yaflet ontl mtam odt “et enti nism edd to [too tedto eft darordt Besotg of entl LCetotttite oft Agrotdt bas , yal eskres mt betosmnoo et tetommaltm odT..°D ts -o8 eTom a tedt oe ,yafet ontl atem edt atin aittmoont edt to atanette edt to sebt aterso ed Briow read hertstdo od Yea eselugmt entl ent£l satan odt to tromevrom edt yd bedetaret vletom et entf£ [stottitevs ef? .erotsmars slot -tsq at yttosqss bare sonmetelteet ofdstartis as yaler enti mtam edt meowted Setoennoo ,felfs fetolttitre edt to maottonct ef? .Sus0ry fae aoteavsosth edt gritedS qe rotlat ed [ftw omti exefqub refog edt to extf atam edt to sxamot eft ; 112 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY relay is connected to the positive side of the local battery; the two points are connect- ed to the two coils of the printer relay, as was the case in the introductory system. The remaining two terminals of the printer re- lay coils are strapped together, and this point gonnected to the negative side of the local battery through a 2000-ohm resistence, By this arrangement, the printer relay fol- lows the movements of the main line relay. The purpose of the 2000-ohm resistance is to limit the current through the printer relay. One point of the printer re- lay is dead. The other point is connected to the positive side of the local battery. The armature of the relay is connected to the receiver brush arm. Hence, when spacing sig- nals are sent out from the transmitting sta- tion, the tongue of the printer relay goes Sff YHTAAOLIST PUITUIAS TO MiTECYe MUSTAHOM HHT to ebte evytttsec eft of bstoonnoo at ysalet -toemtos ets atatog owt edt syrettad Isce0l ant es ,vafer retattq edt to eltoo ow? ext oF Be ef? .meteye yrotoubottat edt mt eeso edd saw -~st totatrq odt to eferimret owt antntanet efdt boe ,seftegot S5eqqarts ers afioo yal ent to ebte evtisszexn edt of betosnnos tatog ,sonsteatesst mio-000S s davordd yretiad [sool efot ysafer rsteitq edt ,tuagoanarrs aldt ra eYSler eaxll atem edt to etnemevom edt awol ot at sonatetaet mio-0008 edt to ssogqrrq edT ysfet tataing eft davotdt taortwo odd timtl -9r totairvg ent to tmtoq end et Botoonnoe at tatog tadto ofT .hbaeh et ysl edt .yrettad [soof eft to ebta evitiaog odf, eit of bstoennoo et ysler edt to orsteors, -ate gatosqe aedw ,ectel .ars davtd revisoet este gaitttioansrt eit mort too tues ste alan 2903 yelor tataiw edt to sxanot edt ,aott 113 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY to its dead point, and the receiver brush is not energized. When a marking pulse is received, | the tongue of the printer relay goes to the opposite point, which is connected to the po- sitive side of the local battery; hence, the receiver brush arm is energized. The opera- tion, therefore, is exactly the same as the system of Fig. 6. The circuits of the local re- ceiving relays have been omitted; they will be considered during the discussion of the printer, The synchronizing circuit,” as previopsly described, was taken from Fig. 24, Hence, no further explanation is required. As for the buttons on the re- ceiver disk, and the circuits which they con- trol, the buttons are arranged just the same as those of the transmitter disk, except that 3 § YHUAHORIAT DQAITUIANG TO METeye MUANIOM FAT ton ef daurd tevieset edt fas ,tmtog bseb att ot eSovisosy st oe Lire goivram es ment! .bestarene edt of seos yefer totaizng oft to ovanot odt -oq eft ot betoonnoe et dotdw ,tutogq ottaogqo sit ,soned gyrettad Iaoof adt to ebte svitte -ste¢o eff festeremre ef ors deuvrd revteocer edit em emee eft yl[tosxe at ,stoteted? ,moit -O ett to matere -et Ls00f sit to attuyorto exAT {fiw yedt ~hetiimo meed svad eysler aaivioo edt to mofeevostb edt antteb batebtenoo ed etotairg etivorfo gotstrordomye of eatt mort movst eaw ,bedtrosed yLayoltverq es ebortuper ef mottenslaxe teddrut om ,eomel .bS ~or oft mo enotisd edt tot eA -109 yeds doidw eftvorto odd Bas ,Meth zevteo omsa edt test Seararrs ers smottud edt , forte ted? tqeoxe .Natd rettiownstrt oft to seodt as THE MORERUM SYSTEM OF PRINTING TELEGRAPHY the two synchronizing buttons of the trans- mitter have been combined into one large but- ton on the receiver disk. This button is marked "A" in Fig. 26, and is called the re- storing button. The receiver circuits beyond the receiver disk will be taken up in connec- tion with the printer. We will now explain the polar duplex operation of the Morkrum System. POLAR DUPLEX OPERATION. The system of telegraphy as presented in Fig. 24 is capable of duplex operation, that is, capa- ble of simaltaneously transmitting two mes- sages: one in either direction. The plan is that of the polar duplex. As in all duplex @haes, the principal requirement is that the home-main-line relay shall respond only to signels from the distant station, and that the distant-main-line relay shall respond on- 114 Sif YHUAAOVRINT DUITMIAT TO MATAYe MUSMAOM THT -enstd edt to saotiod gotsiaordonye owt edt -tod sarsl enc otat Bbeatdmoos weed ovad tettin at aottod efct .xeth rerteser edt mo not -et ect belfao et Sne .3S .2k% ot "A" Bottom etotiod gatrotea booyed ettyvorto tsviesex eT -oommoo at qr sevtst ed [ftw vatbh tevteosr edt stelqxe wom [ftw oW .tetatirq edt dttw xctt moraroM edd to soitareqo xelfqs5 tafoq edt -meteye ed? .MOITAHITIO. XRIIVG HALOT $8 .stl at dbotnoaeta es ydqataefet To meteya -scso ,at tedt ,mottategoe xefqub toe sideqeso at -zem ows gatitimensrt yissosmetfamts to eld ek asfq ofT .mottoerth redtte at exo :sense xefquh {fs mt sA .xelqubh raloq edt to tadt tedt at tnomertiper [sytontrq edt ,eemmtzre vino Buoqeer [fede valet etti-atam-omod ont tedt Bae ,cottata tratath edt mott efeayte ot -10 Broqeet [fede yalor enrtienxtam-daateth oft 115 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY ly to signals from the home station. In other words, each relay registers signals received from the other station, but does not regis- ter signals sent out from its own station. If the relays perform in such a manner, then each station can simaltaneously receive and transmit a message without the interference of the line signals. The circuits essential for a@uplex operation have been separated from the general scheme of Fig. 24, and are pre- sented in Fig. 27. This figure represents two stations, exactly alike. Suppose the main line pole changer at the home station to be on its positive contact, as shown in the fig- ure. A circuit is thereby established from ground at G', through the positive leg of the main line battery, B, through the pole changer contact, to the middle point of the YHCARORIRT OPMITLILI TO METeYe WOM AAT tedvo aI .anottistea emod odt mort pes ot YI Bovteoet afenntea atetatner yatet dose ,ebrow -atget tom asoh ted ,aottste tedto edt mort -fottate awo ett mort tyo tmee afarate tot soft ,rennan s dove at mrotreq eysler edt tI bas evieest yfasoonstiemte nso mottste dose sonerestietmt edt tuodttw sasseem s timanstt wafsmgte emtl aft to tot [sttcease attsorte sit ; mort hetereqsa dood svad mofttateqo xefar5 -9T7 ore bus 228 at to oserfon [steven odt etneszerqet ervalt etdT .¥S .ett at betmee ntam edt? eaoqqueé .etffe yltosxe ,adotisis owt ed ot mottsts emod edt ts teannssio elog oentl -glt edt at mwode es ,tosiaoo ovitteoq stt mo mort foratidstes ydetedt et throrto A .eiw to gel evitteog edt damrordt ,'2 ts brsots ofoqg edt davordd .&€@ .yrettsd entl ateam edt eit to ¢tmtoq elbbtm edt o¢ ,toataoo teqmedo THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY milammeter winding; at this point, the path divides into two branches. One part leads through one coil of the mein line relay, through the artificial line, to ground at G,. The other part goes through the other coil of the main line relay, through the line to the distant station, through one coil of the main line relay, through the entire milammeter winding, then through the second coil of the min line relay to the artificial line, and through that to: ground, Now, return to the middle point of the mil- ammeter at the home station; the current path divides at this point. If the artificial line is properly adjusted, the resistance and capa- eity to ground through the two brenches of the circuit will be the same. Hence, the cur- rent divides here into two equal parts, and, moreover, the two parts build up to their 116 afl YHUAROAIET OAITAIAT TO METeYe MUAWHIOM FHT dteq edt ,tatog aka ts ;yatiatw totemel tm esbsel treq an .2edenard owt ofat sebivts «valor ontf atem odt to [too eno davordt ta baoorts of ,omtl [etotttirts eft davord? tedio oft dasotdt se0g traq tedto ediT . 2 edd davotds ,ysfert eat atem edt to [too exo davordt ,motists tuetetb edt ot enti edt dgsords ,ysfexr eatf{ atam edt to [foo edt davord? sedi ,anthatw rotemmet[tm ertinas edt of yslet enti mtan edt to [toe baoosa ehbavotg of tedt davord? fos ,eatl fatofttizs -fitm edt to tatog ofbbitm edt of axrster ,woll dteq toaerrso edt ggottats omod odt te tetommne exalt (Cstoltiiixs edt TI .tatog atdsd te sehivts -sqso fos eonstateaet eft ,Sstent hea yiteqota alt to aedonstd owt odt davotd? bawora ot yito -rvo edd ,eomeH .omeas edt ed [{[tw thsorto odt ,bas ,stray favpe owt otnt sted sebivth tres xtedt ot qu bitsd atraq owt edd ,rsvootom THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY working values at the same rete. Therefore, one-half of the current goes out over the line to the distant station, and one-half goes to ground at the home station. Hence, there are equal currents in the two coils of the home main line relay; the coils are s0 connected that the two equal currents neutralize each other's magnetic effects. There is, therefore, no resultant movement of the armature. At the receiving or dis- tant station, the currents pass through the relay coils in opposite directions. Hence, the magnetic effects of the currents are ad- ditive, and there is a movement of the relay armature. Of course, if the armature is al- ready in the position to which the line cur- rent ends to move it, there can be no move- ment. Also note that the current at 117 Yit YHIAAORIET PALTHIAI TO METSYe MUMALOM ANT ,etoteted? .stat omee odt tes eoutsy antirow edt tevo to ae0gn tmeturo old to tlaed-seno tled-sno B98 .sotiate tastelb edt ot entlL .oomek .mottsta gmod sit te Bbarota ot seog altos owt edt mt atcexrtso L[aspe ets otedt ets sftoo edd ;ysler omilf ntsm smod edt to stocerrve [ape owt edd tadt hetoenmmoo og -atoette oftenaam a'redte dose estisriven tneaerom tastivesr on ,astotetedt ,st sreAiT -et6h to amivteeeser edt tA .stutamres edt to. edd davordd saszy efaortyo eft ,aotiste tast .o0teH .anxoktoert& etiacoqgo mt aftoe yelor ~bs ots etaetise edt to stostte ottensam edt yaier eft to taxamevom 8 at stedt bas ,evistth -f[e sf eruteorea edd ti ,estsce tO ,otvtsmrrs -to anil edt doftdw ot mottteog edt mt ybser -svom om ed ase etedt ,ti svomw ot ehne toot ot mom ts toe tise edd tadd eton os LA THE MORKRUM SYSTEM OF PRINTING TSLEGRAPHY the home station passes through the milam- meter windings in opposite directions, so that no deflection of the instrument is pro- duced. At the receiving station, however, the current passes through the entire winding in one direction, so that a deflection is produc- ed. Hence, a8 a summary of the operations, we may say that signals trans- mitted by the home station do not affect the receiving apparatus at that station, but are registered by the receiving apparatus at the distant station. In the same way, signals sent out by the distant station affect only the receiving apparatus at the opposite end of the line. The operation of the plan wuld of course have worked out the same had both stations been sending out either positive or negative currents. 118 BLL YHTAHDEIST PALTUIAL 4O MTeYe MUTAAOM TUT -msftm edt dyvordt esersq mottste emod edt oe ,anottosrrdS etteoqqo mt aaugtbatw tevem -org ef toomortemt edt to sottoofteb on tadt edt ,tevewod ,dottsts saivtsser eit tA .heomh xt gatbatw ettine od? danotdt aseesq Ynetti0 -osborg et mottoelteb a tedt of ,mottoerth ono Hs edt to yreame * es ,oomel -soatt efeoate daddy yee yam ow ,anoitsisqo edt footts ton of mottate emod edt yd bettin ere tod ,nottats tadt te exstataqgs antvioser edt ts eutstsqge univteser edt yd beretetser elargte ,ysaw omae edt ol .nxotiste tastelrd yino toetts mottste tieteth edt yd tuo tise Bae etleoqyo edd te autsreqgqa anivieser eit bivow mafy edt to mottateqo edT .entt edt to dtod had sase edt tua beiréw evad eetvoo to to evititeos teitte tvo anthaea meed enottstea eatneriss evitssen 119 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY If both stations are sending out currents of the same sign, say positive for example, we have equal e.m.f's. impressed on both ends of the line. Hence, there is no resultant line current, and of course, no current through those coils of the main line relays which are connected directly to the line. Each relay will, however, register the same as though it were receiving current from the other station. An inspection of the dia- gram will show that the current through the artificial line at the home station will be in the same direction as positive current from the distant station would be. Hence, this current through the one coil of the re- lay produces the same movement of the arme- ture as a positive current from the other station would produce. Likewise, at the dis- tant station, the current through the arti- ert YHUAROAIET QUITHIAL TO MNTEYS MUAAKCOM FHT attbaes ers anottate drod tI evittisog yse ,magte omse ed? to atnerrye to Seesetamt .e't.m.e Lampe evad ew ,efqmsxe tot om si ered? ,eomeH .entl edt to esbae dtod 0 om ,gatveon to bre ,tmetiso emtl trativest entf misnx eft to eftoo exsodt davordd tnettryo eft ot yltoetth betoennoe ete dotdw aysler edt tetetzer ,revowod ,{Iiw yaler dost .antlf mort toetivo satvtsset stew tt davondt es smae -sath edd to aottoeqant aA .sottats rato ent edt dayvordt daexrryo edt tadt words [ftw mara ed [ftw mottate omod edd fae oxif f[stottiias toerryo evitteog as csolttoertsS Adin edt at ,eoneH .ed bilrow cottste tasteth edt mort -ot eft To [foo eno odd dayordt taerrro etdt -serrs edd to tmemavom omae edt ascovborq ysf retito edd mort tnertyo evitteoq s se otut -elb eft ts ,saltwettl .eosborg biyow nottate -tita edt danvordt taerxvo edt ,notiate tast 120 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY ficial line and one coil of the main line relay is in the same direction as a posi- tive current from the home station. Hence, the movement of the distant relay armature is the same as though that movement were produced by a positive current from the home station. Therefore, we see that each relay still registers the signal sent out by the other station, but does so by current from its own station. If both stations were send- ing out negetive currents instead of posi- tive, the operations would be exactly the same, except, of course, the relay armatures would take position against the opposite points from the first case. In case both stations are sending out current, but these currents are of different sign, the operation of the re- Osl YAYAAVE INT OQUITHIAT TO MATeYe MUAAHOM NAT exif ateam eft to [too eno basa ont [stott -leoq ¢ ss mottoerth emee oct at eat yelfor ,9o%eH .mottetea emor edt moxt taermv.e evit ervtsmre valet tnateltbh edt to taemervrom edt etew tnomovom gadt dasodt es omen edt et emod edt mott tnerrso evitteoq s yd beowbotq yelet dose ted? see ew ,stotetedT .nottats eit yd tno tuen Lamgte edt aretetaer [{tite mort tnetrss yd oe eeoh gud ,nottatea tedto enoitveta awo ett -brea stew enottate ditod tI -tnog to besteant etnerruvo ovitaazen tro aat edt vitoesxe od floow amottatrsaqo edt ,ovit serstsnres ysfer edt ,eatsoo to ,sdyeoxe ,omss stteoqqo edt tentane notttacg sxat bilnoow ee2e20 garit edd mort etatog ets enottate dtod sesoe al ere atcetiso esedd ted ,tmet«se to satbooe -et edt to acktsreqo edt ,agte tastrett th to THE MORKRUM SYSTEM OF PRINTING TELGRAPHY lays is not changed. The only effect is the doubling of the line currents. We see, therefore, that by using the instruments and connections of Fig. 27, we can establish duplex operation, that is, we can establish simaltaneous com- munication in either direction over a single wire. The Morse sounder and other instruments of Fig. 24 ere used when the two distributors are being first put into opera- tion. By means of these instuments, the oper- ators at the two ends of the line can com- municate with each other. Since these Morse cireuits do not form a part of the printing telegraph system proper, their discussion will be omitted. We will now take up the des- cription of the only remaining element of 121 £sf YHTARDIAT DUITAIAT FO MATCYe MUANHOM FHT eit et tostte yino ef? .boanado ton st eysl -stoatiye exif eit to antiduoh vd vad? ,oroteredt ,cee e¥ to amottoenicoos Bae etmoemerdant edd gatas -‘tokssrero xefanh dalidetee neo ew ,TS .2ft -moo avoexetfemte delbfdstes neo ow ,et tact efaate = tevo noltoert6 tedtte mi nofttssianm -othy todto bas treSaroe satoli exfT owt edt medw bees ors dS .ati to sinemuttent -steqo otat tuq terit anted ors erotediztalrs -teqgo eft ,atnemstent eeedt to ansem yi .aoltt “moo mao eatf edt te efme owt edt te etots eeroM easedt eomt2 .tedto dose dttw etsotaum anttateyq off to traq s mrot von ob atigorto ackeesoeth rledt ,teqorq metaye dystaetst -Settiao ed {fiw -295 eft qu edet wor [ftw e¥ ‘a to taemefe yuakontamet yino odd? to aottqtto 122 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the distribution system, viz., the Wheatstone differential relay. THE WHEATSTONE DIFFERENTIAL RELAY. The main line pole changer, main line relay, and printer reley, although they do not form a part of the distributor itself, yet constitute part of the entire distribu- tion system; all three are adaptations of the Wheatstone differential relay. The three functions are performed by instruments which are exactly alike in mechanical construction, but differ in their electrical connections. The Wheatstone differential relay is primarily the same in its action as any other polarized reley; that is, it in- cludes a moving contact arm, playing between two fixed contact points, and operating solen- eids. The contact arm takes position against one point or the other, depending upon the direction of the current through the operat- ssf YHLAADARINT OMITAIAL TO Meterve MUAATOM TAT exotetsedW eft ,.siv ,metays mottuyditteth edt ystor [attaerett rh TAITUNANTTIC THOTETARHW AHT extf£ mtem ,teagmado efoq ont£ atem ed? YATES oh yedt davodi[s ,ysfer tetaitg baa ,yalst etloatt totudtateth edt to trsq s mrot ton -ydixtetbh ettine edt to trag stutitanoo tox to saottstqgsis eis serdd [fa ;aeteye cnott setdt of? .yefet isttmetettth onotateed® edt fotdw ateemavttent yd fomtotteq ers enattonut efottorrtecos [sotasdoem at extie ylfosre sts esnottoennoo LIsetrtosfe rtedt at rettth tod {atineretttsb emoveatsad® edt e2 mottos ett af omse edt yltramtiq et ysloer -at dt ,st gadt ;yafex bestrsf[oq tedto yas seowted uitvelq ,ore fostmoo anivom # sebslo -mefos anttereqo fae ,atatog sostmoo hextt owt taniages motiteog saedst mrs sostaoo eft .ablto edt moqs antiaeqeS ,redto edt to sateq sao -tateqo edd davordd taetrvo eft to mottoerth 123 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY ing coils. The armature, however, is not per- manently polarized, as it is in the usual form of polarized relay, but is polarized by a separate exciting coil. The relay may be used as a differential or cumulative in- strument, depending upon the connections of its operating coils. A relay is said to be differential when the magnetic effects of the currents through its operating coils eoun- ter-balance or oppose each other, and cumula- tive when the magnetic effects of all cur- rents add to each other. The Wheatstone dif- ferential relay in its working form is shown in the accompanying plates. The principal parts of the instrument are shown in Fig. 28. The two cores of the main coils, C and C', are mount- ed vertically and side by side. On these cores are wound the main coils, each coil &sf YETAAORIAT OMITHILT TO MATCYe MUAZHOM SHT -teg ton et ,tevewod ,stutsorre eA? .eftoo ant Iecas edt at et tt as ,bestraefoq yitmeram bostrsfog at tud ,ysfet bestrsfoq to mrot yen ysfer ofT .ftoo antttoxe etataqee a Yd -xt evitalsmo to [attimetettib s a2 beas ed to smottoenmooe oft moqn ancthreyzos ,tremmrvte ed ot Blae et yelot A .eftoo anttateqo att edt to atostte oftemasm edt aedw [sitinetrett tb -msoo aftoo anttsteqo att dgvoris strerivo -sfimso Bae ,tetto dose esogqoe to sonelfad-tet -tso Ife to etoette oltenssm edt modw evit -tt& enotatsed” edt .reito dose of Sha etnet mwora et orrot gnivrow ett mt yeler L[aftrerst aetale gatynsqmooos edt at eft to atrsq [satonitq edT owt oct 1.88 walt mt mrofe ots tromorvent -tosom ere ,'9 bas 0 ,eltoo atan edt to estos esedtd aO .ebtea yd ebie Bae yilfsotirev he Itoo dose ,aftoo atam edt Savow sts setoo 124 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY consisting of two separate windings. The ends of the windings are brought out to binding posts on the base of the instrument. Each core is fitted with pole-pieces, as is in- dicated. The armatures, A and A', play between the pole pieces, one armature being at the top of the cores and the other at the bottom. Zach armature consists of an iron disk with a smell projecting tongue at one edge. The two disks are attached to a bress rod, R, which runs through the centers of the disks; brass is selected for this rod on account of its non-magnetic properties. The rod is supported at the top and bottom in pivots, The tongues af the armatures ex- tend into the space between pole-pieces. The exciting coil may also ast YHTAHOATLIAT OQMITMIAT TO MATcY2 MUSAHOM HHT ebme edT .eantintw etetaqea owt to yattetenoo amxtbetd ot tro tdayord ete enathatw edt to dost ,tromurtent edt to ersd ect no ateog -at et as ,sesetq-efog dttw betttt st eros ehbetsoltb A dos A ,eorstenrs ad? erutamrs sxo ,eesata aflog edt neawied yal redto eit Baa aetos edt to got edt te antod na to atatenco erutamts dos® .mottod edd ts tsa osnsot anttcotorq [fame a dttw datb mort 8 ot S5edosite ers asistb owt sdT .enbo ono etetneo odd davordt anus dotdw .f. ,S0r sesrd fot etdid tot Setoefee st assrd :ateth edt to eeolttoqorg ottompam-aon ati to tasooos mo movdod Bas qed edt te hbetroqqre alt bor edT -xe setwismra sdt te sergarot edt .atoviq at -eecetg-elog meewied ossqe eft otat Aaot oels tam f[too gatitoxe eT 125 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY be seen in Fig. 28, As shown, the coil com- prises an iron core, upon which is placed the exciting winding. The core is mounted vertically, and is of about the same height as the other cores; at the top and bottom, the core is fitted with pole-pieces. The pole-pieces are end piec- es, attached to the core in such a manner that they project from one side of the core. Semi-circles are cut out of the projecting ends of these pole-pieces; in the two semi- circular pockets so formed are placed the two circular disk-ends of the armatures, one disk being placed in each pole-piece. A very small air-gap is left between the armatures and pole-pieces, so that the two armatures end the brass connecting rod by which they are supported can turn freely in their pivots. Just above the upper arma- ture, and mounted on the brass connecting esr YHYAROE INT DLITHIAG TO MATeye MUAAHOM HHT -moo [tos edt ,mvonde aA .8S .atl at sees od Beoalg at dotdw moqy ,eroo aort ns esetra Setasrom ef gtoo eAT .amthatw eantitoxe oft tdated emse efit toda to et Bae ,yiisettrey emosvtod bas qot edt ts :aetcs tedto edd es 200elq-elog ditw beftit at etroe edt -seltg Srne sia sesetq-aefog eT Toomtan s dose mt ezoo edd ot bedortts ,e¢ -eroo eft to eble exo mort toetora yedt tadt anttootora edt to tuo tus ets asforto-tmed -tmes owt eft mt ;sesetq-efoq eeedt To absae efit hessfq ere besrrot on stetoog taivorto eno ,eeTutsare edd to ebpe-dteth teluerts ont yrev A .eseltgeefog dose at bseslg gated teth setvtsmre edt soowted ttel ef qss-tisa [Iane serstenres ows edd tedt of ,eeoetq-elfog hae yeds dotdw yd bot sxivoonnoo eastd edt Sas -atovig tktedt mt yloert arot neo betrocqive eta ~sarme teqqy edt evode test guilteenntoo esesd eft mo fetavom fae ,eist 126 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY rod, R, is a contact arm, 0. This arm is fix- ed to the rod, R, at one end, and carries a contact point at its .other extremity. Two fixed contact points are provided, one on either side of the arm and both in line with the contact point carried by the arm. The arm swings back and forth with the armatures be- tween the two stationary points. 4s for the operation of the relay, suppose the two operating coils car- ry currents which polarize the poles and cores in the manner indicated in Fig. 29. Also, let the current in the armature-exciting coil be of the direction that polarizes the armatures es shown, There is no return path for the ex- citing coil flux between armatures except through the intervening air or through the cores of the operating coils; obviously, the flux chooses the latter path, Hence, in Fig. YHIAHORIST PUITMIAL TO MATeYe MUSAAOM Hat ~xit ef ore eidT .0 .mrs toatmoo a et .f , bor 8S eetties foe ,fne emo ts ,f . bor oft ot bs owT .ysinertxe tenfto; efi ts txtoq toatroo no ero ,febtvorq eta etrtog tostace bextt avtw entfl mt dtod bas orre eft To ehte raitte oxe ef” .wre oft yd beirreo tetoq tortnoo edt -ed setutemre odd dtiw dtrot bas wosd aantwe eetatog yrenottste ows edt reowt eddy to sottereqo edt rot eA -ts9 eftos anrttsreqo owt eft seeogqve ,vyelfeot eeTtoe bea eelog ext estraloq dotdw atneriuro yt vor ,oafA .@S walt at beteotiat tenneam edt at ef LItoo ehkerexe loti? eke edd af treriwo est aerrtenrre oft soxsitsfoq tent mottoerth eft to -xe eft rot dteq aurtet om ef ered? .mwode es tqeoxe serutsars meowted xuft ftoo anttto edt davordd to tre antrevretat edt darvordt eft? ,yfarotvdo saftes anttsreqo edt to setos eatt ot ,conel .dtsq retteal edd seeoods xeI[t THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY 18, the flux between armatures assumes the same direction and path as the operating flux. Such action pulls the armature in the direction of the flux; that is, the armature takes position against the right-hand pole- piece. When the armatures are in this posi- tion, the contact arm lie against the right- hand eontact point. Had the operating current been in the opposite direction, the cores, C and C', and their pole-pieces would have been oppositely polarized. Hence, the arma- tures would have swung toward the left pole- pieces until the swinging contact arm made contact with the stationary point at the left side. Therefore, the direction of the working current, by determining the polari- ty of the pole-pieces, determines to which side the armatures will swing, and therefore 127 YETASORINT QUITHIAG YO METEYe MUAZAOM AAT eid esemrses setotemre neewted xolft edt (or gattereqo edt ss Steg bas sottoettb emes edd at etuteore odt elf{ugq anofios dorée ,xult etutaore edt ,et tant? yxft eft to mottoerts -efog bret-tigtt edt tentage oottteod eexat -teaoqg eldd st eta sewwitsorrs edd oof! .soete ~tisils eft tentage etf mre voatmoo edt ,nott etotoq voetmoo hasd tnetivo aritsteqo eit bell ,eeToo edt ,sottoerts ettacqqo edt at reed event Bitrow seoslg-elog ntedd Bue .'O Bae 9 -esute efit ,somed .bestrsefoq yletteogqo seed -sfoq ttef edt brawot annwe eved bivow serut ebhem srre toetmoo untertwe edd Itinw eeoetdq edd tsa tntog yranottate adt ditw toatmoo edt to mottoertS edt ,etoteredT .obte itel -lrefoq oft anictrreteh yd ,trertwo antdrow doitdw ot eenimreteb ,eesetq-efog ext to yt erctetesd fas ,antwe [ftw eersteora edt ehte THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY determines whether the right- or left-hand contact will be closed. If, instead of the direction of the working current being changed, the direction of the armature exciting current had been changed, the armature would have changed position just the same, This move- ment would be due to the change in the po- larity of the armatures. In practice, how- ever, the exciting current of the armature is not changed. In Fig. 30 are shown the three methods of connecting the relay wind- ings when the instrument is to perform its three respective functions. As was said be- fore, each core carries two independent wind- ings, 811 four windings being the same; the windings on each core are shown separated in Fig, 30, but in reallity, both are distrib- uted over the entire length of the core. 128 8st YHTAAOSTIET DMITMIAL TO METeYe MUSACM SHT Brad-ttef tc -tdstr eft tontedw sontarreted «beaols ed [ftw tostnoo noltoottb est to bastent ,tI ent ,beaneds anted tnertyo gxtdtow edd to tasiivo gattioxe exutsarrs est to nottoorth eved Bloow etuteamts edt ,heamedo mood had -evom efdT .emsea edt tert mottteog beaneris: -oq edt xt ennsdo edt ot eh ed blrow taom -wod ,sottostq al .eerutamrs edt to yttrel erutsora eft to taerrse antttoxe ext ,teve ebegaedo ton ef eit ovote ere OS .att ol -betw yelet est unttoonmos to aboritem ee1dt ett mrotreq ot af taemiriant edt new sant ~ed Sten asew eh .anottvonnt evitoereert setdt -batw taehseqehst owt selyteo eros dose ,e10t edt jemee edt arted aanthoatw root [fs ,eant beteteqera mwode era etoo mses mo anntinatw -diateté ers dtod ,ytiitfeer at ted .0& .att at -exco edt to dtanef etttne oft revo bets 129 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY In Fig. 30(a) is shown the relay as connected for action as a main line pole changer. In this case, all four windings are in series, and in such a way that their magnetic effects are cumulative. The exter- nel connections are to terminals a and b. An Spplication of the cork-screw rule shows that when the coils carry current in the direction indicated by the arrows, the top of the left core becomes a north pole, whereas the top of the right-hand core becomes a south pole, The contact arm, therefore, assumes position against the right-hand contact point. if the operating current is reversed, the polarity of the cores is reversed and the contact arm assumes position against the left point. Hence, the instrument fulfills the requirements of & main line pole changer, In Figs. 30(b and ¢c), we see est YETAROALIET QHITAIAI TO METEYe MUAAAOM FET est owota et (s)08 .aktF al entt gies s es sottos tot Betoencos sea yelst agotintw tvot Ife ,eseso sidt ol .tegnade eLfog tted} tact yew s dose nt bas ,eetten at ors -tolxe ed? .evitelsmue ere avoette oftenssm mA .d bes @ elentoret of ers anolttoenmos fen tact? awode efet weror-dtoo ent to softtsotiage sottoorth edt ot duets yrrse elton edt sedw dtel edd to got edt ,eworrs oft yd beteotbat qot eft eseretw .efog Hdton & semoced exoo eefog divoe ge eemoosd etoo Bbuet-tdatr odt Yo sottieog aemunee ,ototeredt ,mrs tontmos eT edt TE .tntoq toetmoo bued-tintz eft tertese ytluelog edt ,beatever et tnorryso adttereqs ars tostioo edt bea Bearever at setoo edt to some .tatog ¢tel edd tanteaes notttecq eommacs to atnemertsper edt efltt fot tremurtest edt sxegsade efor eatl aten s eee ow ,f{9 Sas d}O8 .eotT al 130 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the instrument arranged for operation as a main line relay. The main line relay is un~ der the action of two operating currents: that passing through the artificial line, and that passing through the min line. These two currents should neutralize each other's effects on the armature. At the same time, the relay should respond to a single operat- ing current passing through all windings in seties. An examination of Fig. 30(b and c) will show that the relay will act in the de- sired manner. Fig. 30(b) shows the relay car- rying currents that neutralize, that is, the currents which it carries when messages are being transmitted from its own station. Fig. 30(¢) shows the instrument carrying a single operating current, as it does when messages are being received, In Fig. 30(a) is shown the OsL YHTAAOSIET QMITUIAL TO MITeYe MUAAHOM THT & a8 coftearteqo tok boaneste Sneourrtent edt -ng ef yefleor onti miam efT .ysfert enti atam satmeriso anttstredo owt to mottes edt reb ,onti Letotttins edt devordt anteesq tadt esed? .entl mtam oct davoult anteesq tad? bae a'tedto done estiettxem bivode efmertse owt ,emts emea eft tA .erxetenrre est ao etooette -tsteqo efacte e ot Buoqeet Siyode velfet edt okt enetiotw (fs davotdt arteesaq taetise got (9 bre d)OS att to mottanimexe oA .eeites ~ef eft mt toa [ftw ysaler otit tadtd wode [ilw -%80 yeler eft eawode (d)O8 watt .tennem borte edt ,et teadt ,estferiven tadt ettiert1i9 aniyr ers eeneerem catw seixvreo tt dotdw etnerrso enti .oottsta mwo att mort bettimenatt acted efanta 2 antyrtso tnenmurtent ost awode {9)08 eexesesen neaiw ee0b ti es ,tnertive anttsteqo ebevieces anied ets ext mwa et (B)0€ watt al 131 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY relay connected for use as a printer relay. In this case, there should be two sets of windings; current through one set should cause the armature to take position against one point, whereas current through the other set should cause the armature to take position against the other point. Two windings are therefore provided, each consisting of two coils, one on each core. The terminals of one winding are a and b; the terminals of the other are b and co. Terminal b goes to one side of the operating battery. Now, if terminal a is connected to the remaining side of the battery, the armature assumes position adjacent to the left pole-piece. If, instead, terminal c is connected to the remaining side of the battery, the armature shifts to the right-hand position. Hence, the position of the armature depends upon which of its two féf YHUAHOLIST QUITMIAT TO METEYE MUAAAOM FHT evsfer tetacitq s es een rot. Bstoentoo ysfot to estea ows ed bisode exedt ,eeso etdtd al essso S{yode tee ono duvordt tnettse jeantbhbalw eno tentese fsolvieog eta? of etuteanra odt tee tedto edt agvonrdd tnertyo esotedw ,intog notttacg etat ot eantenrrs edt cavao hivode ets egatiatw owl .tatog taito edit sentsga owt to anttetsanoo dose ,hebivorq esotetedt to alsniatet of? setos dose mo exo ,ettoo to afsenimires edt 3d hoe e ers gitthatw smo ov aeca d [sntateT .0 Bae d ote recto edt ti ,wol .yrettsd suantisteqo oft to ebtea emo ehte antntemer oft ot Setoenmoo et s Lantatret coltteog senseas stutemre oft ,yrettead eft to ebsotent ,ti .,secetq-sefoq ster eit ot Taecsths ebte anintemer eft ot 5botoontmoo at o Lantmredt ext of ettine orntsares eft ,ytected ent to to noitteog edt ,esmeaH ,nottleoqg Sansd-tdutt owt ett Yo doltdw aoge ebasqed etutears ont 132 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY windings is energized; this is the action de- sired in the printer relay. It should be noted that the windings are not energized simaltan- eously, but only one at a time. In Fig. 24, conventional sym- bols are used for the differential relays in the different functions. In the diagram, each instrument is shown as having two coils, just as the usual type of polarized relay. However, if it is remembered that the Wheatstone dif- ferential relay always has two coils, though they may be on the same or different cores, and that changes in the opgrating currents in these coils produce exactly the same ef- fects as the same changes would produce in an ordinary polar relay, no confusion on the part of the reader will result. In the wiring diagram, the armature-exciting coils are o- mitted for the sake of simplicity. YHIAAFDEINT DHITAIAT AO METSYE MUSAHOM THT -eb cotter eid ef efdd sBosiaiteme et esntieiw beton ed biyode tI .yalet reining and at botte -netisnts bestareces ton ers eagntbatw eis tadt eemttd 8 te exo yino tud ,ylasoe -ayve [snotinevnoo ,s8 watt ol ot ayefer festénerettib edt rot beer ore efod fose ,merneth edt mI .enottonst tmetett th ent tent ,aftos owt geived as nwode st toemmrtect ~tevevoH .¥ysier besixsfog to eqyt I[sver edt as -tth enotetsed” oft saft bersdmemer at tr tt davodt ,sftoo ows eed evyawia yefot Istinetet ,eeTc6o toeTettlb +o emse edt mo ed yam yedt etnertro gantteraqo eft at eegnede tedd Bae -te omes et yiteszxe soubotq altos esedd xt nt ecwbora Bfisow sentado omen oft ee etoest adit ao molestaoo on ,yafer refog Yranifbto as goitiw oft xI .tiveet If tw tebeet eft to t1aq -o ete afioo unittoxe-erctarre eft ,mearasth eyttetiqmte to exse eft tot betiina THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY The last paragraph. concludeg the discussion of the distribution system. Next will come a description of the printer. As in the foregoing material, rough sketches of the printer parts will be used to show the general principle of action, whereas the photographs of the actual machine will be relied upon to show the detailed construcion of the machine. 133 1 YHITAHVEIST OUITHIAT TO MATEYe MURXHOM EET ashulonoo \ dgersgetse¢ teel ed? emetev2a dottediztvath odd to moteesoetb odt etotnizng eit to mottqtreesh a emoo I[I[itw txre® eedotexe dasot ,[stretam gniosetot ent mi eA wore ot boas od {[Itw etteq tetnitq odt to eit esetedw ,tottos to siqtontrq [ereren oft ed [ftw ontioan feutos edt to edqersotodq solomrtenco bellteteh aft wore of noqu hetler onidoar ant to THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY Part IV - The Printer. GENERAL. The Morkrum printer is, in reallity, a typewriter, operated by electro-magnets which are controlled by the incoming line impulses. In the following des- cription of the machine, the plan will be to take up first the mechanical movements of the printer, and then to explain the electrical means by which the mechanical movements are operated and controlled. The complete printer may be seen in the accompanying plates. As is indi- cated, the main frams consists of a bed-plate, from each corner of which rises a post; a cov- er-plate is screwed onto the top of these posts. When the machine is completely assem- bled, it is entirely enclosed except for the platen and typewheel carriage. The printing action in this machine is accomplished by the typewheel striking a message blank, which is supported 134 S5L YHLAHDEIOT DMITUINI TO MNTEYe MUSHOM FHT etecaini edi - VI traf tednizg avrdroll efil .TASHWHD yd hetersqe ,tetinweqys s ,ytiifesr at ,et edt yd betfovtnoo era doftdw, stensgsm-orltoele ~b8eb aniwoflot edt aI ,eesfrqmt sotl antmoont ot ed ftw amelq eft ,entisoam oft to nottaire end to etremovom [sotcsdoem ett tertt qu sextet {Isettiosle odd atelfqxe of nodt bas ,tetnizta ets eteomevom [setnsdoom att dotdw yd enasem eAeflortnes bre betareqo ed ysa setaing etefqmoo eft -tbot et eA .eetalg gniyrsqmooos edt at noes .otelq-bed s to etatenco emart atem edd ,botae -voo 8 ;teoq s& sealt doltdw to temros dore mort esedt to got edt otmo Bewotsea at otalq-te «meses tlotefamoo eat satdoam edt nei .eteor est rot tqeoxe beecfone yLeritiae et ti ,beld eexeiyrse [sedweqyt bas cotalq eldt mt mottos anitatra eT feenweaqyt edt yd beratiqmooos et eninosm fetrogqse et dotdw ,ansld ogsseem s anitdizte 135 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY on the platen. These warts are shown in the assembly photographs. THE TYPEWHREL. The typewheel is shown in Fig. 31. It is a fiber drum, a- round the edge of which occur the type in raised characters; the characters are arrang- ed in two rows, one near the top and one near the bottom of the drum, The typewheel has a hub at its center, the hub being bored to fit a shaft called the typewheel shaft. This shaft furnishes the primary support for the wheel. THE PLATEN. The platen is a rubber roller, whose purpose is to hold the message blank or other paper. It is similar to a typewriter platen, and will be taken up in detail a little later. THE TYPEWHEEL MOVEMENTS. There are a number of necessary movements of the typewheel. Primarily, of course, the wheel él YEUASOEIST OUITHIALT YO METEYE MUANAOM FHT edt at awode ets etrar csedl .netel[q et mo -adgaersotodq yidmesas {eedweqyt edT .ISEHVSIYT FHT -s ,muTh todit a ef ti .[8 .2tf of awode et mt ecyt eft tyooe riotdw to egbe edt barot -onsTtts ers exoteastadio eft j;etetssrsdo beater teen exo bas qod ott rsen eno ,awor owt at Be & ead L[esdweqyt eft .motb edt to motitod ent tit oF Horod gated dud edt ,z9etmeo ett tea dod ttede ata? .ttede L[eedweqyt edt helff[so ttade s Leow eft tot troq¢ss yramizrq ed? sedetnrut set netsf[q¢ efT .HETAIT FHT eft Bflod ot et seoqusq seaodw ,telfor teddst tefimte ef tI .reqsq teito ro dnald eagsasem qs sextet ed Iliw bae ,notelq tetirweqyt a ot etetel ealidii se L[tateh at etedT .cTWXMEVOM IESHWALYT HHT edd to atnemevom yreesesen to redmiun s ote foedw edt ,satvoo to ,yfiremixi .Leedweqyt 136 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY must strike the platen so as to print the character. Before this action, however, it must have rotated so that when it strikes, the proper proper raised character will be at the point of contact between the wheel and platen. Also, the typewheel must be in its correct vertical position, that is, the correct position along the axis of its shaft. If the wheel is in its normal position, char- acters of the top row strike the platen; if the wheel be raised a little, characters of the bottom row strike the platen. This lat- ter is called the shift position of the wheel, and is assumed when the shift signal is re- ceived over the line. Furthermore, after the printing of each letter, the typewheel must be spaced, that is, it must be moved along in front of the platen a short distance, so that the next letter pfinted will lie beside él YHTARVEIST QUITHIAI TO METAYe MUAZAOM FHT edt salrq ot es of metelfq eft exixte tearm tr ,tevewod ,mctios etd? esoted .retsaetado ,sosixte 2f sedw tad? oa betator eved teum ed {[iiw tetoetaeto beetaxr teqortq reqotq est feedw eit mneewted toe2etn00 to tatog oft ts ai od tenm L[ooedweqyt efit ,osfA .motaly bae ed? ,ef tadd ,sokttaog [soitrev sooxsroo ett etisde ett to atxe edd qrof[s mottteog toer roe -tedo ,cottleog LIanarrom att at at [sedw ext tI tl ,setelq ext sitrze wor qot sat To etetes to atetoerado ,efitil a boatet ed Leodw odt -tel etd? .netsl[q eft extrte wor mottod ext elvoedw ed? to softtteog tide eft beffen at tet ~-or at fenante titdse ect sedw hemraaa eat hoe ent testa ,ctomrettast .enil ext tevo hevteos term L[oodweqyt edt ,tettefl dose to antinizg giofs bevomw ed tesm tt ,at tadt ,beoage od on ,ecomatetS ttode » setala add to tnort at ebteed otf I[ftw betattq rettel tres ott tedt THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the preceeding one. It is important that we note that in this printer, the platen remains stationary, whereas the typewheel travels back and forth in front of the platen, and thereby distributes the successive charac- ters along the printed line; in the ordinary typewriter, the platen carries the paper be- fore the point of printing, but in this case, it is the printing point which moves. And last, when the end of a printed line is reach- ed, the typewheel must be moved back to its starting position. With this idea of the type- wheel movements, we are now ready to study the means by which these movements are accom- plished. THE CARRIAGE. The typewheel is supported on a carriage (see Fig. 32). The carriage travels back and forth before the platen, carrying the typewheel with it. As is indicated in the general views, the car- 137 ver YETALOAIGT DHITHILZA TO METCYe MUAAHOM FHT ew tedt tasizogmt at tI .eno gatbeesstq et exntsmer netelq eft ,rstaitg etdi at teddy eton efevet? [serweqyt edt esetenty ,yrenctiste bas ,metefaq eft to taort at dgrot bas Mord -oxtedo oviesecone aft aetudintels ydetont yrenthiro eft at yentl fetnixc odd amole aro? -ed teqeq eft asetirso nets[q sit ,retirweqyt oes atdt ot ted .getinixg to tartog edt etot Sok ,sevou doltdw totogq smttattg eft af tL -foset et sail Betaitq s to Sas edt nedw , vast att ot siesd Bevom ed teu Isendwegyt edt , be -oqy?t ent to esebk etdt ath’ soottteog satdiretea ybote ot vhseer wom ets ow ,atnomevom Leodw -mooss ers atsemevom seedtt dotdw yd easem eat ebedatiq Ieeiweqyt edT .GWATHHAO SAT ef? ,(S8 .aki een) esetrrso ea mo betrogque et est exoted strot bse soad slevetd esairreo eA .tt dtiw L[eedwoqys odt aatyrise ,netsla -Tao eft ,ewetv [stores eft at betsstbhat ef THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY riage is supported on two square steel rods, which extend clear across the front of the printer just in front of the platen. The car- riage is so constructed that when one of the rods is turned, the typewheel strikes the platen, when the other rod is turned, the typewheel assumes the shift position. Hence, these rods not only form a run-way or track for the carriage, but also serve to transmit energy to the carriage for the typewheel move- ments. Because of this arrangement, the elec- tro-magnets operating the typewheel can re- main stationary, and be rigidly attached to the frame of the machine. A third rod, simi- lar to the other two, but not assisting in the support of the carriage, is located be- low the other two rods. This third rod serves to transmit the motion of rotation to the typewheel. We see, therefore, that the car- ~ 138 asf YETAROUIET OQUITUIAT TO METEYE MUSRAOM SET -8bor L[ecte etanpe owt mo betrogque ef easi2 edd to tnort edd esoror rsefo brotxe dotsdw -7s¢ ed? .wetefq edd to tmort ab tert retnirg ent to emnoj;medw tadt beteusttenco oa at sgeie ect asiixte Leedweqys ect ,bemrst et ebor edt ,bearut ef Bor tendto eft medw ,netala ,eoneH .mottteocad ttide edt sonuaes L[soedweqyt dost xo yaw-owr 8 orrot yimo ton ebor eesdt dimesaert of evres ols tud.,egetrrso edt ref ~8V Onl Leotwoayt ext tot exsixreo et ot yatere -oete ond ,trcomegnetzs etdt to eaveosd .atoem ~et meo L[eedrecyt edd anitareqo etsugem-ort ot bedoatia yilbtate od bas ,yrecofttetes ata -iute ,So% briant & .omtdosm ont To emart odt mt antietass fon ted ,ow? redio edt ot «sl -od Dstscof st ,eneteras edt To droqqua edt eevies Sot hbitdd atd? .,shor owd redto edd wol eft ot mottstor to mottom edt simeaetd ot ~tso. eft tad? ,eroteredd ,eea eV .Leedwoeqyt 139 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY riage serves as a support for the typewheel, and also transmits to the wheel the movements of rotating, striking, and shifting. The complete carriage is shown in Fig. 32. As the mechanism is rather complicated, we will take up, one at a time, its various functions and the parts concern- ed. The carriage frame is shown in Fig. 33. It consists of two parts. The first is a yoke, which is supported by the two steel rods as stated before. The yoke is fitted with round collars, free to turn, which have square holes at their centers; the holes fit the square supporting rods, so that when the rods are turned, the collars turn with them. The second part of the casting is of the form shown; it is attched to the yoke by two small shefts in the bearings. eél YECAADRIGT DAITHIAT FO MATCYe MUATAAOM ANT e{eeiwecys ont tot vroqqye s es eevres enetr atnemevom eit Lfeenw edt ot etimenett oefa base eartttide Sas .grtdicta ,aattator to ef szelitas etefqmoo exAT tedvat at metxadoom edv eA .SE .att of cworlk ,emtd a ts exo ,gu exXat [ftw ow ,botsotfamoo -resioo ettag edt bas amottonst esotrav est - be mvora at omart sastrrso eAT edt .etteq owt to atatemoo tI .88 att ot eit yd bettoqqya eat dotdw ,etoy se et tertt et exioy eff .etoted betsta as aber [oote owt dotdw .arut of sett ,atsf{f[oo basor dtiw hbetttt eefod oft :atetmes ttedt ts sefod srsrpe evad sedw tedt o8 ,ebor amttroqque etaspe edd ttt dtiw arst arsffloo edt ,benrrst ota efor odt to at anttaso edt to trsag baooee oft .modt yd sioy edt of bedotts eft tt jawode mrot edt -eattrsed edt at atisde [fame owt THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY In Fig. 34, we see the es- sentiel parts for rotating the typewheel. The bevel gear, B, is mounted on the lower end of a vertical shaft, 3; at the top of the shaft is a universal joint. A sleeve, A, is attached to the upper member of the uni- versal joint, and into this sleeve slides the typewheel shaft, F., The upper end of the shaft carries an arm, called the locating erm, which locates the typewheel. The type- wheel is set onto its shaft with the locat- ing arm extending into one of the holes in the bottom of the wheel. The shaft, F, is at- tached to the collar, C, which fits over the Sleeve, A, The collar, C, and the shaft, F, are joined by a small pin, D, so that the the collar and shaft can move up and down a- long the sleeve, A, This mounting is neces- sary in order that the typewheel may move to 140 ODL YHTARORIAT DAITUIAI TO MATSYe MUTATOM THT -a8 edt cea ew ,d8 walt al -faetiweqys edd anttstor tet atrsq Istines tewol edt ao betavom et .f .tseq Leved eT to qod eft te; ,ttsde [sottrevy s to ine eA ,oveolfs A .tntot fastevtas 3 eat stada edt -tav odd to tedmem tecas eit ot bedostts at aebifs eveel[s etdt otat Bae ,fatot [seater edt to bas taqas ofl .t ,ttade [sedveqy? edd anttesol edd Sef{fao ,orts me setrtss stada -egyt off .feedweqyt adt setssof dotdw ,mrs -tsool edt dttw tSade att ofao tea et [sedw mt ssfod edt to emo ofmt gaotbmetxe ams ant -ts et |, Made of? .feody oadt to mottod edt edt reve stit dotdw ,0 ,teffos edt ot hosdort «% ,ttade oft bar .9 .zslloo ef? .A yovools eft tentt oe ,7 .atq [lame a yd Seato§ ote -8 a7ob bas qu evom mao ttade fos taffoo eft -aecen et anttnvom eid? .A ,eveete eft anof ov svom yeu Loedweaqyt oft tad? tebro mt ree Ss - 3 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the shift position and may still be rotated. The purpose of the universal joint is to al- low the typewheel to strike without disturb- ing the gear, B, and the shaft, S. Fig. 34 also shows the method by which motion is transmitted from the rota- tor shaft to the gear, B. A second gear, =, meshes with the gear, B; this second gear, E, has a square hole cut in its center, so that it fits over the square rotator shaft. Hence, when the rotator shaft is turned, the gear, E, is also turned, so that the typewheel rotates. The gear, E, fits the rotator shaft loosely, so that the gear can slide along the sheft with the carriage, and be in mesh with the gear, B, In Pig. 32, we see the rota- tor parts in place on the carriage frame. As is indicated, the second casting of the car- 141 fat YHIARVAITT DUITMIAL FO MATCYe MUAAROM AHT ehotator ed ([f{tts yem hae cottteoq Hida adt -fa ot st tatot Issteviasw edt to saoqrug edT -dtusvatbh tuodiiw etirte ot [oodwoeqyt edt wol oc ,ttede oft bas ,.f .t898q eft gat Sodtem edt awode oefs £8 .9tt -ad or edt mort botiimanexrt st nsottom dotdw yd 22 41899 baooee A .E ,t892 edd o¢ ttade rot .2 ,t8903 booose aldt :;¢ ,rs9e3 ott dtiw esdaen teadt oe ,tetnes ett at tvo ofod eterpea es aad ,eonsH .ttsda rotstor etsryoe edt tevro atit tt ,2 ,t803 oft ,bearstd et Jiade totstox eit mosh eastator f[senwoqyt edt tad? of ,dentut osf{s af eTleeool ttede totator odd attt ,2 ,1raes eT ttene edit amofe ebtis aso 188g eft tadt of et} dtiw deem at od bas ,easivtas edd dttw ~& ,Tse2 -stor edt o98 ow ,S& .stT al eh .emett essixrse edt mo eosf{q at atraq tof -tso edt to anttaso baooea sit ,Sstsotbri. at THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY riage serves to support the sleeve, whereas the lower casting holds the shaft, F, of Fig. 34. Fig. 32 also shows the gear guide, by which the gear, E, is drawn along with the carriage. As indicated, the lower casting carries an arm extending downward, and this arm supports a collar bearing for the gear E of Fig. 34, The striker movement of the carriage is shown clearly in Fig. 32, left view. To the coller, which fits over the striker shaft, is attached a lever, #25-4, the upper end of which is connected by a link, #25-5, to the upper casting of the car- riage frame. Hence, when the rotator shaft turns (to the left), it turns the lever, #25- 4, which movement pushes the typewheel to the left and downward, The carriage in this latter position is shown in Fig. 39. 142 ear YHIAHOAINT DUITAIAT FO METSYe MUAXHOM FHT asetediyw ,eveele edt trogqqra of sevtes ogait eBtt to ,2 ,ttade sdt ebfod xuattsso towol odt vd ,ebtira tases ed? ewode oefs SS .2tt .d8 edt diiw anofs swath et ,2@ ,rseg edt dotidw anttase towol odd ,Sotsofiat ef .ousiitss eidt bor ,Stawawob anthaetxe mre as eeirrss tees oft rot anitsed raffoo ea atroqqya mrs 35 .a2tt to & edt to smoemevom textrte adfT Itef ,SS .gft wt yltsefo awode at osgatixtrao edt rsvo aftt dotdw ,rsf{foo oft oT .welv »d aidt mt easttrss od? .Srswtwob bas ttel edt 88 .ght at mwode et xotttescg zetitsl 143 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY Note that the joint between the carriaege- frame castings is in line with the univer- sal joint of the typewheel shaft; hence, the carriage can bend over like a hinge. A centering device is added to the striker movement of the carriage in order that the raised characters of the type- wheel will always hit the paper squarely. Onto the typewheel shaft is attached a star- wheel, #25-14 (see Figs. 32, 35, and 36); the star-wheel is so placed that the spaces between its teeth lie directly below the re- spective characters on the typewheel. A cen- tering lever, #25-19, is mounted on the car- riage frame as shown in Fig. 36. This lever is pivoted, near its middle point, to the carriage frame; the lower end carries 4 cross- pin, P (Fig. 36), which fits into the slot of @ transverse cam, This cam is rigidly attached “hed or & YRIAAPRINT DQUITHINT TO MaTeYe MUSAHOM THT -ensirrso edt meewted tntot edt? ted? etot -tovins oft ditv entif at et santtaso emstt edd ,somed ;ttade foodweqyt odt to tmtot [sa eagntd s extl revo bred 129 exetrrss Sebbs et estveb attretmes A at egsitrse eit to taomevom reiatrte edt of -eqyt ait to sretvoertsdo beatat edt tacit teSto eUlotenmps teqeq edd tid ayawle [Itw [seidiw -tate s ferfostts et ttede Lfsedweryt edt ofn0 7(a8 bee ,38 ,SS .aatT oon) AL-38% , Loos seoscge eft tedt Beoslq o2 at Leedw-tsta eft ~et eft wofed qitoerth etl dteet att nsewrted -teo A .[sedweqyt edt mo atetostads eviiseqe -189 edt mo bedavom at ,eL-88 ,revel yatret revel sidT £388 .3tt at mwode ea omert egsit edt ot ,tatog ofbbim ett rsem ,Betoviq eat -ge0ts a eetrtse bae tewol ent jomart easiritso So tole edd ofut atit dotdw , (88 sft) I .ate Sedosttes qlbtalt et mso etdT ,mao earevansrd 2 144 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY to the lower casting of the carriage. Ordin- arily, the centering lever is in the position shown in Fig. 35, but as the carriage is bent over for the striking movement, the relative motion of the cam and centering lever is such that the upper end of the centering lever en- ters one of the spaces between the teeth of the star-wheel. Both the aibee end of the centering lever and the spaces in the star- wheel are slightly V-shaped. Hence, as the lever enters the space, the star-wheel and typewheel are not only brought to center, but are locked in that position until the end of the stroke. The parts are returned to their original positions through a reversal of ro- tation of the striker shaft. The shift mechanism may be understood from Fig. 32. The collar which fits over the shift shaft carries an arm, A. Saf YHTAHPAIAT DHITMIAY TO METeYe MUAAHOM FHT ~aibrO ,eaatrtss edt te anttaso rewol edt ot mrotttsoq edt ai et tovel antretmes ed? ,ylirva toed st sasiznrso eft as tid .d& .3f% at mroda evitsfer edt ,tnoemevom gaidizrta edt tot revo ifoss at revel amtretmeo bas meo edt to nottom ~te tevel gatrotmes sit to bae teqqu edt tadt to dteet odt asewted seosqa edt to ono eret eft to fae xreaqr edt dtod .lesedw-rste ant -tate edt at seoave edt bas tevel antretaeo edt as ,eonmeH .beqadte-¥ yitdetlfe ers foedw bos L[oedw-tate sd? ,eosqa edt arotne revel tod ,teataes ot tdyvord yino ton ets L[sedweadyt te bao oft Ctinuw nottteog tadt nxt Sexool ots xtedt ot hbhemavtet ors eitag ofT .ovorte oft -or to [sersver s dusotdt? srotiteog Lantatro ettade teitrtes eft to nottst ad vem metnadoom tiide od? dotdw raffoo edT .Sé sali mort Sostesokas eA ,mrsa os selrrso ttede ttide odd revo atit THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY By means of a link, this arm connects with the vertical sliding rod mrked "shift plun- ger", This rod slides up and down in the bear- ings on the main casting as is shown in the figure. To this rod is attched the clutch, #25-7, which is merely a flat plate. One end of the plate is attached to the plunger rod; the other end is forked, and fits over the end of the coliar (C of Fig. 34) on the type- wheel shaft. When the shift sheft is turn- ed (to the left), it turns the sleeve and the arm, A, This movement reises the plunger, #25- 42, which movement, in turn, raises the clutch collar, typewheel shaft, and typewheel. The typewheel is thereby moved into the shift po- sition. A return spring on the carriage brings the parts of the shift mechanism, in- cluding the shift shaft, back to their normal 145 GSI YHIAHSRIZT OMITHIAT TO METSYe MUSAAOM FHT dtiw atoomroo mra etd} ,~nvif » to ansom yo -culq Stide"” fextam bot gathtie L[setirev srt -rsed sit at mwob bare qu sebtf{fe bor etdT ."teg edd ot mwode 2t es anttaso xtam edt mo eant efotelo edt hbedotis at hor eitdt oT .otoultt bro enO .etelg talt s ylotem ab dotde , T-884 bor tega Ig edt ot bedoatts et stsfq edt to eiy tevo atit Bus ,bexrot at Bae tedto oft -sayt edt mo (8 watt to 2) seffoo eft to hae ettede Loew -atay at ttede siide odd sod’ edt Bas eveole eft enrud tt ,(dteLl eft ot) Be -a8% ,regaclq eft seatst taemevom etal .A ,ors dotefo edt seetsar .atet mt ,tromevom dofdw ,Sd ei? .feedweqyt fas ,ttste Lesdweqy? ,talfoo -og ttide sit otnt Sevom yderedt at feedweqyd ecottie ensitrtas eft mo gsairqe oxster A . -ti ,aatasdoem dttda edd to ettaq edt agatrd Ismrton ttedt ot Hoad ,ttade dtids edd aatbulo 146 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY inoperative position, This spring is shown in Fig. 32; it is stretched between the spring bracket, #25-10, on the plunger, to the lower part of the carriage casting. The inker is the device by which ink is smeared onto the typewheel face during the striking movement; the ink is applied just before the wheel strikes the platen. The inker consists of a small felt roller, soaked in ink, and mounted on sup- porting levers. These levers are attched to the frame of the carriage. As this device is mechanically simple and unimportant, it is omitted from the detail drawings; it is shown, however, on the assembly photogrephs. THE ROTATOR, STRIKER, AND SHIFT? LINKS. The means for turning the ro- tator, striker, and shift shafts are shown in Pig. 37. This figure also shows the meth- od of supporting the shafts on the main bear- aby VETAZDEIET DAITHIAL TO MaTeye MUAAHOM AT mwode ef antuqe stat ,motiteog evitsteyont gnitqa edt nsewied bedoterse at tt ¢SS .altt at rewol edt ot ,toanulg edt mo ,Of-d8% ,totoard esaiteso ezsiizss edt to Treq yd eotveb ett at revni oT sost Lfoedweqyt edt otro betaema at ast doitdw et Act sdt bstoenmoo ots aidt mort beflortnoo ets aysist otalq ont eseoging tot ,el{daeivbe emese tl .tee baooea edt to nella ett qu b{tsd ot ,woltensl{qxe to etafg Bas Zool sid asewted etiverto Cortncs eayeist .CTIUOHIO YAISH BHOOL ET -artertt bee eyaler dool edt to enottoonnoo edT olf ot yl[{sottamedoe awofe: sta xXeltbh tetsin oved OS .2t% to ayefer aool edt sect eto% .8s edt at aysafer Isool edt to eesrtq edt nedst -tsothat ef eA .8 watt to mateyse gotvediuterb edt wt eev[oemedt Asol ayefer Hooft edt .5e ayelet stafq eff es tes mottiaog avitsteqo -19 anttool ef? .emedoe anthesseta edd at ob davordd eemoo ,tevewod ,saso edd at trot rtaftwte ,yalot dtxtea ew to stostxoo daoad edt 195 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY to the others, and called the selector break. The circuits are so arranged that when the selector break coils are de-energized, and the armature lies against the back point, the locking circuit is closed to the battery; when the coils are energized, the armature is drawn away from the back point, and the locking circuit is separated from the bat- tery. Hence, when the selector break opens, it releases any of the lock relays which have been locked in the operative position. The control of the selector break is through a button on the receiver disk. This button, called the restoring but- ton, is double size, and corresponds to both the positive and negative synchronizing but- tons of the transmitting disk. It will be remembered that once every revolution of the transmitter brush arm, a marking impulse is sent out from the negative synchronizing but- ser YATASORIAT DUITMIAT FO MATSY2 MUAATOM GHT -Msetd totesfee edt befifeo hans ,etedto edt of eit medw tedt begnatrs of ets atinerto edT Bas ,bostareme-of ete eftoo Aserd totoelea ~tatog dosd edt fentsass eet{ eruteanrs edt suytettad edt ot beaofo et ttuoxto aatdool edt erstemre edd ,hestaureme ote eftoo sit nedw edit Bre ,tatoqg wosd odd mort yews awerb ef -tead edt mort beteatsaqes et sitsettoe antxool ~emeqo Xsotd totoslee oft medw ,eoneH .yred even dotdw agsle1 Aaool edt to yms esasefer tt -cottteog evitsisedo ad? at fexool ased totoefee edt to Lortioo eT revieset edt so sottod s dagvord? et deed -tod antrotest edt Beffse ,sottud atdT .vetb ditod of ebmoqesertroo bas ,este ef[dvob ef ,mot -tud antsinorfoaye evitegen bas evitteoq edt ed [ftw tl .deth gatttimenart edt to anot edt to molttuLovet yreve eoso tadt bersdmemet et sefuqmt aytsdxrem s ore david rstiimescatd -tod antstrordeaze evitegen eft mort two sites THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY to; hence, the selector break is energized and operates once every revolution of the brush arms. Furthermore, the opening of the selector break occurs between successive let- ters, so that the lock relays are "restored" after the reception of each impulse combina- tion. The lock relay, L-5, does not lock itself in position with current from the selector break; we will presently see the reason for this fact. It might be well to state here a condition which is general in all the Morkrum circuits, viz., one side of the bat- tery is permanently grounded, and one side of every solenoid or relay is permanently grounded, Therefore, only one additional path need be established between the battery and the magnet in question, 196 eer YHTAAHRIAT OUITMIAL FO MATS Ye MUAAHOM BHT Sestetene et Aserd rotoel[ee oft ,somed yot edt to notgufover yreve somo gotarszo fra eit to antaeqo eft ,stomtedii? .emte devtd ~tel evicesoove meewted erseo0 wee1d tosooelose “fhototsex" ers ayafer wool edd tad o8 ,eted -antdmoo ealuqmt dose to aottqeser edt t6tts molt . geoh ,a-1 .ysfler wool edT txettso dtiw mottteog at tleett soot ton yltnesetq [[lw ow ;ieertd toteefee edt mort etost eid tot moaget sft coe stete ot [Lew od tiatm $I edt £fe wt Lerenes 2! Sotdy mottirbroo s ested -ted edt to ebte omo ,.stv ,stivgorto mrrmdrotf ebte sno boa ,bobavors yltmenaoreq ef yret vitconamtreq et qeist to bhomefoe yreve to dtaq [enotttibea emo ylno ,etoteted?T .bebnavots bes ytetiad edt meowted bedetidstae ed Soen erorteerp at tengam edt ae ah aoe 197 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY THE LOCK AND PLATE RELAY CIR- CUITS. The connection from lock to plate re- lays is shown in Fig. 49. Here we see that the five plate relays are connected in paral- lel with their respective lock relays. The two sets of instruments are connected in par- allel through four back contacts of a relay known as the divide relay. Plate and look relays #5 form an exception to the general arrangement: they are connected directly in parallel. The plate relays lock themselves in the operated position by current through the min break, just as before, although the locking circuit is not shown. By this arrangement, if the contacts of the divide relay are closed, as they are when the divide relay is not ener- gized, the plate and lock relays are in par- @llel. The plate relays will, therefore, fol- low any movements of the lock relays. Since yer VHTAROSIPT DUITHIAT TO METSYe MUSAAOM HT -AT0 YAIGH RTATLT CWA AOCGI FHT -et etstq otf Xool mort mottoenmoo sdT .eTIUD tadt ese ew steH .Od .2atW xt mworte ef ayel -fersg at Sefoonnmoo ete eyelot stsfa evit ont adi .eyefet dool aviteeqesor xiedt dittw [el -raq mt fetoemron ete stnemuttent to eter owt ysier s to atoataoo xoed twot davordt Cells Moot Bae etall .ysfor ebtvt5 edt as avond [aromen edt ot mottceoxe ma oot @ aysfot mt yftoettb bets anos ers yend :tremegcatts eevisemedt dool evefer etelg oct .fel(s1sq dasomnt trevrve yd motttaoq Seteteqo edt at edt devodt(s ,stoted se tes, ,xserd aiem edt eMwode ton at titrvorto anttool edt tt ,tceregnsirs atdd yi es ,Sevolfs ete yeflor ohtvtS edt to etostaoo -trere ton et valet ebitvith edt nedw ete zodt -teg “ai ers eyefer xoof bas etsia sit ,boesta -fot ,etotetent ,{[ftw aysfor stafq oAT .Lolls eonte .eyefer fool ext to atmemevom yos wolf 198 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the lock relays are governed by the incoming line impulses, the plate relays also register the character of the impulses. If the contacts of the divide be opened, as they will be when the instru- ment is energized, the two banks of relays are separated. The first four lock relays act just as before, but the plate relays are not affected by the line impulses. Since the locking circuits of the two sets of relays are independent, the plate relays remain in the position in which they were at the open- ing of the divide contacts; then, when the main break opens, locking current is cut off from the plate relays, and they resume their inoperative position. As for the operating circuits of the divide relay, the relay coils are con- nected to one tongue of the relay. The back point, corresponding to this tongue, is con- beL YHTATHE IST DUITHIFT TO METAYe MUAAAOM ENT anitmoont eft yf hextovon exs eyelet wool ent netarnet oels avelor etsiIq edt ,eeefsgqmt entl -seefugqmt edt to refestaro edt ebivibh edt to sioetmeos adt tI -ortamrt eft nedw od [ftw yodt sa ,beneqo ed eyafer to ered owt eft ,besisrene ef sSnom eyelet Hoof tot terkt esl .botareqea ets ers ayefer etealq oft tud ,cxoted ae tes, tos ext sont? .eealuqmi oatl odt yd betoetts ton eyafat. to etes owt oft to aetisorto antiésol ot ctemet eysier etalg edt ,tinobmoqebot ets -meqo oft te exow ysdt dotdw at aoltteog eft eit nedw ,nedt getostnos ebiIvith edd te ant tto tuo eat torture astvool ,smeqo Aserd ciem tied? omuset yedt foe ,eysfer etelq eft mort noltteca evitetoqont ativorto anttereqe edd rot @A -noo ete altoo valet edt ,esfler ebivih edt to Zosd efT .yafer edd to examot smo oF betoon -coo et ,exgnot etdt ot untbnoqeerroo ,déntog ry THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY nected to the restoring button of the receiv- er disk. When the relay is in its usual po- sition, there is a current path from the re- storing button, through the brush and brush arm, through the divide relay contact to the operating coils, and thence to ground. Hence, when a marking pulse occurs at the restoring button,as it does once every revolution of the brush arm, the divide relay is energized. It therefore draws its armature against the front contact, and thereby cuts itself off from the receiver disk. As we shall see pre- sently, the front contact is connected to the battery through the main break; hence, the divide relay is locked in its operative position until the opening of the main break. At the same time that the divide relay has changed its own circuit, it has separated the lock and plate relays. Ny rf tol , wi +e oy eer YHTARORINAT OMITHIAT TO METCYe MUAAHOM THT -viaoer oft to nottnd untroteer ont of betoon -og I[sver ett at at yafer eft mon .detbh to -et eft mort dteq tnerrss @ ef erodt ,nottte desrd bae deurd edt dasort? ,nottisd antrote edd od teetnoo yalor ebivibh edt dguvordd ,ore ,eoneH .invore o¢ somedt fae ,altoo antiateqo gatteteet aft te eryooo selsq anidtam s ooedw to motdufovet yreve eeno seoh wi as, nodind -Sestateme et yeler ebivib edd ,arra desrd edd eft tentses srutsmres ett ewesth sroteveds #1 tto Yfeati etme ydetedt Bae ,tostnoo taort -etg eee {fate ew ef .xetbh tevteoet oft mort ot betoennoo ef stostnoo tncrt edt ,yiitmes ~soned ;Axserd mitam eit duvordt yretiad oft eviteteqo ett at betsof et yealet ebivib ext etsetd ate efit to gatneqo edt [fttav mottteog ead yelet ebitvitbh eit teds emtt emsae ont tA beterages ead tf ,tlrorte mwo dst heanario eyelet eteafq Ans wool eit THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY When we go a step further, and apply the scheme just described to the scheme of Fig. 47, the result is the circuit presented in Fig. 50. 4s was said before, Fig. 50 shows the lock and plate relay cir- cuits actually used in the Morkum printer. FINAL SELECTOR CIRCUITS. In Fig. 50, the lock relays are connected to the receiver disk just as in Fig. 48, and they receive their locking current through the back contact of the selector break. The first four relays are connected in parallel with their respective plate relays through the back contacts of the divide, just as be- fore. The fifth relays are connected direct- ly in parallel. The five plate relays and the fifth lock relay receive locking current through the main break. The selector break and divide relays are connected to the re- storing button of the receiver disk. The di- 200 OOS YHTAROELST DUITMIAT FO METcYe WUHAHOM FUT erott@t gets 2 os ow rod! eft of hedivroseh gest emoedon edt ylage bas tinotto oft ef tivaert edd ,TA .ett to enonoe ,etoted Brse caw eA .08 walt at betassetyg -tte yefor etefq hae wloct edt awode Od .2tt totatxg modroM edd at bees yl autos ettio aI ,eTIVOsAIO HOTOMIMe LAWMIE ot betesmnoo ers eyefer wool edt ,0d watt hoe ,6S watt at es teut deth revieser ont davordd tastxrso goftool artedt evteser yedt ed? .¥eerd rotesefee edd to vostaoo toad sit fef{fersq nt beteermos sts evefet root tert? dayvordt syafer etslia evitseeqeer iatedt dtinv -ed een test ,ebtvtb eft to etoetros wosd odt -toorlb betoonmoo ere eysfet dgvtiIt odT .erct Bae eyelet otelq evtt oT .feflereq af yt daerzrvo goivool evieoet yefer Yoof dvtit edt ; wsetd totoefee oft .Hserd mtsm edt davordt -~evy edt of betoenmmos ers eyelet ohivith baa -fh edt .teth tevteoet est to nottud satrote = —— poe Ue ne 1 Re YY, moi POF wv Y - * «hip he 7 Vrs 201 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY vide relay receives locking current through the main break. We see, therefore, that al- though the arrangement of the figure has been changed somewhat from that given in Figs. 48 and 49, the electrical connections are just the same. There are, however, two additional devices in Fig, 50. The first of the new devices is the drum magnet and drum switch. The drum magnet is connected to the battery through one of the front contacts of the divide, so that the magnet is energized while the divide relay is closed. Furthermore, the drum mag- net carries oa switch called the drum switch; this switch closes when the drum magnet is energized. The purpose of the switch is to connect the battery into the distribution cireuit, as that circuit is called which serves to operate the rotator magnets or other print- er functions, That is, the drum switch con- £0$8 YHTAHORIET DUITHIAL TO MATCYS MUSAHOM ART fiasordd tuerrve anivosol asvitsssr yelet obtv -fe2 tadt ,eroteredt .ee8 oF .Naeetd ateam sdt mood esd eryatt ocd to tnoamesnerra odd davodt 8) .entt at nevis tadd mort tedwemoe hSeanado vent ets esottoennoo [sotrvoele eft .e) bas Ianotiibhse owt ,tevowod .ets oven! -omse ent -O8 ,at% ot eeotveb eeotveh wer ent to teartt ed? morh oft .dotiwe morb boe veryem murtb oft et davordd yretted edt ot betosmmoo et tongam oe ,eohivts eft to etositnce trort ext to exo ebivth eit eLfdw bestetene ef tesgem edt teadt -gem murh edt ,orormedtrs! .besolfo at yelor efotiwe meth eft Belles dotive se aottrsas ten ef tTergem mtb ede stedw eseofo dotive etdt of et dottwe eft to eeogrsg sd? .bostetomne mottudirterS edt otnt yretted edt toennoo sevies dotdw belfse ef ttvetto tadt as ,titvertto -tnitg tadto to etemgsm rotator eft stareqo ot ~tioo dottwe mab eft ,et tedT .enotsonrt +e THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY nects the battery to the semi-automatic func- tions of the printer. The other additional feature is the signal lamp. As is indicated, the lamp is controlled by an additional lock relay, identical with the other lock relays. “hen a marking pulse is received by the lamp but- ton, the lamp lights, whereas if a spacing pulse is received, the lamp stays dark. The action is apparent from the diagram. We will now trace through the cycle of operations with the system of Fig. 50, remembering that the idea of the scheme is to allow one letter to be printed while the next letter is being received over the line. Suppose, for example, that the signal ++——Hthe letter A) is received. The action of the lock re- lays is for instruments #3, 4, and 5 to oper- ate, since the relays respond only to marking 202 808 YETAROAIZT OLITHIAG TO METEYeS MUARAAHOM FUT -onnt oltsmotys-Imee eft of Yiettsd oft eftoon tetairg ett to erott stxteset L[anctttbhbs tonto ed? qmefl edt ,beteotbat et eA .qmel Ieanste eit et eyvafer wool Ianctitbbse ne yd felfortmoo at rod” ,eyator wool tedto ed? dttw Isottrebt ~tod gual edt vd bevieset eat selinug anidisa s avtosqe @ tr sastedw ,etdsil qmel oft ,not eit «atab eyate qmsf edt ,fhevteoet et safuq smsrgetbh eft mort toerscqs et mottos est dasordt gostt won [fiw sv eatt to metaye oft dttw anotteteqo te eLloyo egetoe et to sebi eit tsdt acitednemet 8 elidw Betnitq ed of rettel emo wolfs ot et eit tevo hevtecer avted el tettel txen ent {sugte edd tedt ,sfqmeaxe tot ,eveogque antl ebeviteoet at (A tettel edt)-—— ++ -et Zool eft to mottos en? -rogo ot @ Boe .d .Si etmomertent rot ar yet. guidtsm o¢ yfoo baoqeer eyelet oft sonia ,sts Pier i ae 204 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY pulses, and #1 and 2 to remain inoperative. Lock relays #3 and 4 lock themselves in the operative position with current from the sel- ector break. The five plate relays duplicate the settings of the lock relays, and #3, 4, and 5 lock themselves in position with cur- rent from the main break. L-5 is also lock- ed by current from the main break. This ac- tion takes place while the receiver brush is passing over the five contact buttons, #1, 2, 3, 4, and’ 5. When the brush reaches the restoring button, the selector break and di- vide relays are operated. The divide relay separates the first four plate relays from the lock relays and locks itself in position. Hence, the separation of the lock and plate relays is maintained after the brush has left the restoring button. At the same time, the Selector break cuts off locking current from 208 YHIAROSINT OUITMIAY TO MATAYe MUSAHOM SHT eoviteteqont nismet otf S fas [% buna ,eeelug est mt sevfecmedt Mool S bana S¥ eyelet wood -fee edt mort tasirxvo Athy noltieog evitereqo etacitfqnuh eyefor otelq evit sXiT .xeerd totoe od ,8% bas ,eyeler wool eft to eanittes ent -10 dtiw cottisog at eevfeemess soot d@ bas -Hool oafe et 4-1 .teerd ates edt movl inet -s2 aint ,aserd otem ont mort daetrso yd be deoxrd tevtsoer ect eftdw esata satst scott f% .erottyd tostaos evit eft tevo sateeag at 2 Soa ,8 ,8-.8 edd sedecet destd edd aedl -ib Bas Heerd sotoel[sea oct ,nottud antroveet vefer ebivifh ed” .beteteqo ota ayalet shiv mort eyelet ovelq twot terit ext eestaraqes cotttaoq at tloet! exool Bree aysfet wool ont etela bos woof adt to nottetaqes edt ,oornell Stel sad decid oft vetta beatstatem ef eyelet ext ,omit emee edt tA .mottad gxtrotver odt mort tnexrrve anttool tto etre xserd rotoelee 205 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the first four lock relays, and these relays resume the inoperative position. The fifth lock relay remains locked with the fifth plate relay. The selector break remains energized only as long as the brush is in contact with the restoring button, but this time is long enough to allow the relays to unlock and as- sume théir inoperative positions. As a result of these movements, we have lock relays #1, 2, 3, and 4 de-ener- gized, and #5 still energized and locked in position. Plate relays #1 and 2 are inopera- tive, whereas #3, 4, and 5 are energized and are locked in position. The selector plates are therefore set, and ready for the print- ing operations to begin. Besides separating the lock and plate relays, the divide relay has, at this time, completed the circuit of the drum magnet, This magnet draws in its armature, 80S YHTAROAIAT DUITHIAT FO METeYe MUAAAHOM FHT eyefer esedt boa ,eyeie: wool trot terlt edt cid t% ediT .sotttecq evitereqont ext Smrveet etelq Avtit edd dA¢iw bedool antemer yelot dool heatoteme enismer xsexrd totosiIse en” .yelst itiw tgosinoo at ef deutd eft es goof as yino goof al omtd etnct tad ,notted antroteet eft ~es bore Moofos of eyelet edd wolls of Agvone -anottteoc evitsregont riédt ems ,etnemevom eeedt to tinest sp eA -rere-9h 3 boa .& .8 Li eyelet dwool evad or at heslool fas besturene [ftte 3% base , fests -ateqont eta S boe £% ayeler stell .octtteog bos besistene ers @ Bae ,) ,8) aastedw .,evit setslg zosoelee ed? .xottteogq at bsiool ets -tntaq edt rot ybset baa ,tes etoleredt eta eaitged of anotiareqo ant tool eft gniteraqer aebteed ts ,ead ysfer ebivib eds ,eysler etelq bas myx eft to ttnorto ett Setelqmoo ,emtt elnt. ,otutamre att mt ewerth temzsm ald? .temzem THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY and thereby sets the interference pins of the selector. The drum magnet also closes the drum switch. This switch connects the battery to the printing functions, so that the printing action now takes place. In the mesntime, the lock relays have been receiving the first two or three line impulses of the next letter, and have stored these impulses by the locking of the lock relays. The final movement of the printer, during the printing of a letter, momentarily opens the main break. This mo- mentary opening cuts off locking current from the divide and plate relays, together with L-5, for a sufficient intervel of time for these instruments to return to their normal positions. Note that the unlocking of the divide relay restores the drum magnet and 206 a0 YHIALDSRINT PUITMIAG TO METEYE MUAAROM SHT to arta sonetettetrt eft etee ydered? fas eerolfo cafe tenmgem murb ed? .roteefsea edt eat atoenroo dottwe etdT .cottwe morh ont tent of ,emottonet antinixng edt ot yretisd -ecalq sextet wor acites gnaitnaing edt adool edt ,emitnsem ext ni to owt terft edt antvteoet meed evad eyelet Bas .tovtel txen eft to eoalsamt. ont setdt goisiool edt yd eselsqmt eeedt betote evad -eyeflor tool eft to eit to taenevom L[axtt en? tettel as to satinivg edd sntryh ,retnirq -om etd? .deerd mtam erit enoqe yiitetasmom mort tnerxvo sattool tto etno amineqo Yretner dtiw tedsegot ,eyefer otelq Sane obitvih edt stot omit to {Isvretat tnetotitvee a rot ,a-1 femros tledt of oyster of aetnomurtent eaedt att Yo ant¥ootas ext tact stoi! .eaottteor bas venzem murh eft seroteet yefet shivth 207 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY drum switch to their inoperative positions. The operation of returning the divide and plate relays, with the other printer parts, to their normal positions is known as "clear- ing” the printer. As soon as the divide relay assumes its normel position, the plate and lock relays are again connected in parallel. Hence, the plate relays immediately assume the positions of their respective lock relays. For example, if the first three impulses of the next letter have been received by the lock relays at the time the printer is clear- ed, and these three impulses are}-—+, then P-1 will remain inoperative like I-1; P-2 will operate, just as 1-2 has done; and P-3 will, like L-3, remain inoperative. The re- mainder of the series will be registered by both sets of relays, just as before. The print- ing of the second character then proceeds, YHTAADAIET OUITAIAT TO MATCYe MUSAAOM GET -enotditeog evitstseqont rtedit ot Aotiwe morb bose ebiviS eit antouvter to mofttereqo eft .etrteq teotning tedto edt stiw ,eyseler otsiq -teefo” es sword et anoliteoq Isatom tredt of etadaizg eft "ant yafer shtvib ext sa moce eA bes etelq oct ,mortteor Lenton etf semees efel{fersq mt hetoennoco aiaga ete eyelet adool emrpeas ylotatbemmt ayeler etefq ont , sone esyeter fool evitoegesr thoedt To enctiteog exit to asafsamt seetdt serit eft tt ,elqmexe sot edd yd hevieser need eved tettel trex edt -tnefo et retaturq oft emtt oft te eyelet dool neit ,, .ets eesluqmt eetit evedd brs , he 2-2 <¢f-f exXtl evitereqont steamer [[fbw [-7 S-T here yemoh ead S+f en text ,etatedco [ftw -et ofT .eviteredont stemer ,S-1 etl ,Lftw yd boxetetger ed [ftw setrea ent to reintem ~tatraq off .etoted es test .syefer to atee dtod e8beesortq medt tetostado baoosa eft To ant 208 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY just as in the case of the first, The reason for not connect- ing the lock and plate relays #5 through the divide is now apparent: The plate relays are always released before the fifth pulse of the next character is received, so that there is no need of separating the relays. By this arrangement, then, we can print one letter while the next one is being received over the line. The printer in this form responds satisfactorily to the rapid transmission of signals. As was stated before, this arrangement just described is the one used in the Morkrum printer. Before we take up a study of the functional circuits, that is, the cir- cuits of the rotator, striker, shift, and other operating magnets, it seems advisable to consider the construction of the electri- cal equipment of the selector circuits just 808 YEIAHDLIAT PUITAIAT IO METeYe MUSAHOM FET etetit eft to sree ent at es teu -toennos tom tot moener ef? edt dgvordt a4 aysfet etsig hae wool edt ant ere aysier etelq edt :tretsqaqs wom al obtivth to eefsq AtTit edt eroted hoaasslet exsaris erent tant of ,bevieset et tefostsdo txem edt -eyetor oft antterscee to been on at ,fedt ,tnomegnatrs atdit 4% eno txem edt eltdw tettel smo fnitq mao sw totaixg eft .entf£ edt revo hevtsoer anted st edt ot yltrotostetiee abmoqeer mrot etdt ot besvate esw 2h .efeagte to motesetmanatt btgst at bedtroseh teut tnomegastss atdt ,stoted etotaitq muriroM edt mt beas exo edt vbutea s au exieat ew stoted ~tto edt ,at tadt ,stivetto fanottonxt edt to bas ,ttide ,rexvixrte ,totstor eft to ettuo efdesivis amase ti ,atemgam atitsreqo tedto -trtoofe edt to moktourtanon edt tehtemoo of test atisetto totoefea edt to tmenugispe [ao 209 THE MORKRUM SYSTEM OF PRINTING TELEBRAPHY described, INSTRUMENTS. The lock, divide, and selector break relays are standard "U" relays, such as are used for the relay pole changers; the divide relay, however, is fit- ted with three tongues on one unit and two on the other. The two units are connected in series, so that they act as a single relay. The lock, selector break, and divide relays are not included in the printer itself, but are mounted separately, as is shown in Fig. 51. The instruments are attached in a row to an iron base plate, the combination being known as the "A bank”. The plate relays are quite similar to the U relays, except that they are fitted with plunger cores. They there- fore act as operating solenoids as well as relays. The other relays of the print- eos YHTAMGSIST HRITUIAT TO MATcYe MUSIAOM FHT eSedttoeeb ,obtvib ,deol ed® .cTUMUAT CUT ‘ "0" Srsioete ets avyelet Xsetd rofseloa ins sfo¢ yslet edt tot bear ors es dose ,eyelor -tit ei ,revewod ,valer efivib edt j;ers_asdo owt bos tinu ero mo aesgnot scetdd diiw bet at betoonmcos ots etitaws owt edt .tedio edd ao Ysfer ofygnta-e aa tos yodt Ted? of ,esttres ~asetd totosfee ,dsol sd edt at Sebufont ton eres ayatet obivih bas eTlotereqse betavom ots ted ,tfoatt tetaitg ete etnemurtant ef? .f[3 .2tt ot mwode at as edt ,staiaq oaed sott as of wot e at Bodostis "deed A" oft as orond arted sottsatdmos eiivo ers eysiet etal ont yedt tadt taeoxe ,eysfer U edd of tellmte -stedt yodT .aoetos tonnelq dtiv bettit ere es {few es ebtonefoe arttarego as tos stot eayslet -tatnvq eit to aysfer tedto edT 210 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY er are either U relays or else instruments similar to the plete relays, according to their functions. A separate description of each device is unnecessary, since the con- struction of each is indicated by its pur- pose. The arrangement of the re- lays in the printer is shown in Fig. 53. There is a back view of the printer shown in this figure. All the relays with the ex- ception of the shift and main break relays are mounted on the relay bracket, previous- ly described. The latter two relays sre mount- ed on the shift relay bracket. The drum switch is shown in Fig, 43. As indicated, it is a single contact switch at the left end of the drum magnet. The switch lever is attached to the yoke of the drum magnet, so that when the magnet is energized, and the yoke is drawn toward the OLS YHITAADEIET QUITHMIAI FTO METAY@ MUAXAOM THT etasmsttedt safe to aysler U tendtte eta r9 ot anmtbroosos ,aysfet stsiq edt of teltmtea to nottqitoegeh staraqger A .emottonst ttedt -mtoo edt eonts ,yresasosmmy ef sotveb dose -ruq ati yd betsothat at doze to sottonurie 980g -at odt to taemensearrs oT -S@ .ot% wat awode elf rotmixg edt af syst nwode tetaizrg eft to weiv aoed s at otedT -xe sit dtiw eyslot edt LfA cexegtt stdt at eysfer aeerd miem Sas vitisie eft to anottqeo -syotvert ,tedsrytd usfer edt mo hetavom ets -toirom eva syaler ows tettsl eiT .beditoseb yi etaxoard yefor Pride edd ao be ot awode et dotiwe mrb edT tostnoo efgarte s et tt ,botaotbat eA .55 att etongan avrh edt to bre ttef sdt tea dotiwe to sxoy est ot Bedoattes at revel dotiwe edT et tergsnm eft medw tedt oe ,tengeam mrch att edt hiuewot awetbh et sdoy edt bas ,bestatere 211 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY right, the switch is closed. Ordinarily, the yoke is in its extreme left position (as in the figure), so that the switch is open. The main break is shown in place on the machine in Fig. 52. It is lo- cated at the left end of the printer, and is supported from the frame. The break con- sists of two heavy contact points, one of which is fixed, and the other of which is mounted on the end of a lever. The two points are normally held together by a spring. The lever is pivoted to the supporting bracket. The beck end of the lever carries a buffer, which lies in the path of an arm attached to the striker shaft. Therefore, when the strik- er shaft turns, it opens the main break. An electrical means is also provided for opening the main break. A solen- oid with a plunger core is located below the Its YHIALVALET PRITUIAT TO METSCYS MUSAHOM SAT edt .yfireantirO .Sesofo st ciottwe edt ,tdaltey nt as) motttsoa Ytef omertxe atk at st exoy emeqo et dotitwe edt tadt oe ,leryytt edt ait mwode et Meord miem oft -of at ti .S@ .gtt at ontdoam edt no eoslq hoe ,tetatiq edt To Bae ttel edt ta hetao -noo swserd efT ,omart oft mort betroqaque af to eno ,etmatoq soatnce yvset owt to etete et dotdw to tedte edt bane ,bextt at dotdw etatog owt ed? .tevel s to Sune edt no betavom edT .amtvge s yd tedtesot Brod eflemrom ete etexostd antixroqqye edt ot betoviq at tevel erettnd e astrtse revel eft to hae atosad eT ot Bodesiie ars as to dtsq edt at eesti dotdw -aitta edt medw ,srotered? .ttaede rettrte odt AseTd stan odd eneqo ti ,antwd ttede te oela et amsom [sotrtosle mA -mefoe A .asetd ateam edt antnego sot bebtvotq edit woled Setssol at estos resmelg a dttw blo . 4 212 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY contact lever. A plunger rod extends upward from the core, the contact rod being in the peth of this plunger. When the solenoid is energized, it draws up its core, the plunger, and the end of the contact lever. This move- ment of the lever opens the break. The plun- ger is ordinarily held down by the spring, as is indicated. The electrical means of open- ing the break are used when a line signal is received which requires no striking action of the typewheel, for example, 2 carriage return signal. No striking accompanies such a signal, so that the striker shaft cannot open the main break; the electrical method must be used instead. OPERATING CIRCUITS. The next subject in the order of treatment of the print- er is the operating circuits, as distinguish- YETAMDSIRT DAITHILI TO METeYe MUAAHOM THT brewqu ebaetxe bor teanutq A .revel sosinoo edt mt ranted bor tostaon edt ,ot00 edt mort at btomefoe edt med s1]egas(q atdt to dteg etosmula edt ,otos ati qs ewath st ,bSesterene -9vom std? .tevel tostmoo edt to fae edt bas -nofq endl .faerd edt aneqo tevel edt to tnom eanttqe odd yd aowob bled ylirenthto ef tes -botsotiat et as -meqe to ansem [soittoefe oat et [anste eatl e medw heas ots draotd edt ani mottos antdittea om setispet dotiw bevisoet ezetrres s ,elymexe tot ,leadweqys edd to dose setnmaqmooos gatditts of .isrste atotet tonmao Itsda reiitte odt teadd oe ,isdate es bodtom LIsotttoele edt :vsetd mien eft mege eSsetent bear ed tamm txen edt .eCTIUOHIO DUITAREIO -tnttq edt to tasmtsett to tebro edd at toetdre -detrenitarh es ,aettuette acttatreqo edt af te8 THE MORKRUM SYSTEM OF PRINTING TRLEGRAPHY ed from the selector circuits, just described. In general, it may be said that each individ- ual function, such as that of rotation, lin- ing, etc.,has its own permanent local cir- cuit. This local circuitreceives power from the battery through a second circuit, known as the printer distribution circuit. This cireuit should not be confused with the cir- cuits of the distributors: the two are entire- ly distinet. The printer distribution cir- euit is not a permanent one,but instead, its character depends upon the setting of the plate relays. The distributing circuit re- ceives current from the battery through the drum switch, so that the individual functions do not operate until this switch is closed. In the detailed description of the operat- ing circuits which follows, the general plan of treatment will be, first, to present the 213 YETARORITT HPUIDAIAT TO METAYe MUSAAOM HT eSedixteseh teut ,etisortoe tofoefee eft mort be -Bivthbat dose tedt Brea od yam tt ,feteteg al -ttf£ ,mottstor to tadt ee dose ,nmottoast [sey -tto [s00f tox onamred avo evi esd,.ote ,gat mort tewog reviecottinorto [socl eatdT .tiso aswoux ,ttsotto broose 2 dasotdd yrettad odd efc™ .tiverto sottudiatels tetatiq edt es -tto edt dtiw Sseutnoo od ton bluode ttyotrto -eattme ots owt oft :etotudinteth edt to etiso -tto sottudiatelb setuatrta edT .tonmtteld yi att ,ieetent tud,eno tnenamted 3 ton ai sino edt to gatttos edt moqe »eabseqeh tesvoarsado ~91t tiverto anttudivtealh ef? .eyslet etelq oft Agvordt yrotted edt mort, tasirts9e aevieo anottoast Laubitvtint edt tedt om fotiwa mtb -Seeo0lo et dotiwe atdt [ttn steteqo toa ob -tateqo edt to mottatroesS beltsteh edt Pad mefq f[eteneg oft ,2wolffot dotdw stivotto gat eft taesetg ot ,tettt ,ed [ftw taomtsei? to 1 Wi . hs See es : be oh 3% bk pi ss & -id , : + Oa are THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY individual circuits of the rotator, striker, and spacer functions, i.e., those which are automatically performed during the printing of a letter; second, to explain that part of the distributing circuit which is concerned in the action of these functions; next, to describe the individual circuits of the shift, spacer and backer, rub out, and liner, i.e., those functions which require special line signals for their performance; and last, to show that part of the distributor circuit which supplies current to these latter funo- tions, ROTATOR CIRCUITS. The rota- tor circuits are shown in Fig. 54, Here, the right and left rotator magnets are connected together at the point A, which point is ground- ed through a reley called the print relay (not the printer relay); the purpose of the print relay will be explained presently. The two 214 ats YHTAHDEINT DUITHIAG TO METeYe MUARHOM FHT etotinte ,totator edt to etisoxrto Isubivibat eta dotdw seodt ,.e.f ,emottonst teosqe bas aatiaixg eit antrsbh bemrotteq y{leotiamotus to traq tsdt atelyxe ot ,faooes y;retteL a to hentsoneo eal dotdw titverte antiudtrterh sdt ot ,txem j;enctioaut ssedt to mottos odt at ettide edt to ativetto LanbtIvthat edt edtiroaeb .-o.f ,tentl bas ,tro dst ,rextead bua tes9878 ext{ [ateeqs sttycer dotdw emottonst esodt ot teal bre :senaemrotteq ttedt rot efsnate tivertto totudtrtetbh sdt te trad tadt wode -onut tetteal eaeds of tnerise eotiqaqne dotdw ~exoltt -stor efT .e8TUdNId HOTATOR edd ,etTeh .46 .9it wt mwode ets etisotito tot Hetooennos ors etanzem totesor Stel bas tdaltt -bavotg et tatog dotiw ,A tatogd edt ts redterot ton) yeler tntaq eft heffso yafet s davotdt be taing edt to seogtg ett ;(yslet tetmitq edt owt ef? .yftnseeera hentalyxe ed [ftw yslet 215 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY remaining terminals of the right and left rotator megnets are connected respectively to the first front and first back point of the relay P-5. During operation, the tongue corresponding to these points is connected to the battery, this connection being estab- lished through the distributor circuit. In the operation of the ro- tators, if the relay P-5 be de-energized, (as is indicated in Fig. 54) the first tongue will lie against its back contact so that the left rotator magnet will receive current. The energy is supplied to the megnets by the closing of the drum switch. If the relay P-5 is energized, the tongue will lie against the front point; hence, the right rotator will be energized upon the closing of the drum switch, instead of the left. Hence, through the agency of YHTAADRIGT OULITMIAT FO METCYe MUSAHOM FHT ttef Bas sSdeatt est to afantarret antatsamet ylevitosqaet betsennos ata etenzam totator to tatog xaoad tertt bas tnort sarit edt of eranct edt ,mofteatreqgo antred .é@-i yelor ods Hetoennoo at etntog esedt of antbaoqastroo -dSatee anted rofteennoo etdd ,yretied edt of ettgottoe trotudiatetb oft desotdt bedetl -or edt to motteteqo edt al ebestatens-eb ed &-T ysfer edt tr ,atotat eyanot tarlt edt (42 .9fT at betsoltbalt at ee) tadt og goatmos doad att taenteage eti fLiw .tmetryo evieost [fiw tenasm totetor tieLl edt edit yd atengan edt of betfqaque et yateme eAT eSotiwe av1r5 odd to anteolo ~Soatarome at a-T yefot oft tI statog teort edt tantens eff [ftw esanot edt bestetene od (ftw rotator tiatr sAt ,sored hestent ,dotiwe murs edt to aateofo eft noqu to yoreas ett davordt ,somsH .ttef edt to 216 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the relay P-5, the fifth pulse determines the direction of rotation of the typewheel. Note that the print relay is connected in the circuit in either case. CENTER LETTER CIRCUIT. In Fig. 56 is presented the circuit utilized when the letter D is printed. This letter is so located on the typewheel that no ro- tation of the wheel is required in the print- ing of the letter. Hence, the distributing eircuit diverts the current from the rota- tor coils, and passes it through the center letter resistance instead. From this resis- tance, the current path is through the print relay to ground as before. The center letter resistance is a coil of the same resistence as either rotator coil, and is used for a compensator for such a coil when absent. When the center letter line signal occurs, afsS YHIAAOATIFT DAITMIAT TO MATEYS MULAHOM AHT eectmrreteb eafuq agit edd ,a-I yalexr edt Leedwoyyt oft to sottstor to nottoerts edt ai Sstoenmoo ef ysfert tattq odd Sadt etol -9e89 tonite at tivetto edt mil .fIVONXIO HATTA AGT festitts ttrorto eft hetmesetq et a6 watt testef atdT .Setatrq eat I rettel edt mondw -ot om tedt [sedweoqyt ext mo Bbetsool oe at -tntrq edt ot bettsper et Leedw edt to nottat auttudhrteth edt ,geneH .retitel ext to ant ~stor edt mort tmerrys edt atrovib sivetto tetmes edt davortt tt eesasq Sue ,aftoo tot ~ateet eldt mort .beeteant eonstetaer totiel tatrq odd dasvord? et dteq tnottso edt ,somet tevtel tetneo of? .estoted es bavora oF yelot eomsatsteer emae efit to [too s ef sonstateor gs tot beas ef bre ,[too rotsetor redite es .tusede cedw [loo eg dose tot roteanognos .ervooo Lanete enti nottel tetnes edt mas” 217 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the third tongue of P-5 is connected to the battery through the distribution circuit and drum switch; the third front point is con- nected to the center letter circuit. The fifth pulse of the letter D is marking, so that P-5 is operated, and the battery thereby con- nected to the center letter circuit. SPACER AND STRIKER CIRCUITS. In Fig. 55 we see the spacer and striker cir- cuits and also learn the purpose of the print relay. The spacer and striker coils are con- nected in series, so that they are energized simultaneously. As is indicated, the current path leads through the striker coils, through the second front contact of the print relay, through the spacer coils, first front contact of the print relay, through the main break, battery, and ground to the striker coils again. The circuit is not closed unless the main break is closed and the print relay is in the ¥IS YHTARORIST DAITHIAT TO MATeYe MUAAHOM AAT edt ot hetoermoo et @-2 to exsgrod Sritdt ont bae gisorts aoftndinielh eft davsordt yretisd -noo et tafog tnort bSrtdt odd ;dotiwea moth cstit ed? .tivorts tetfef rotmes oft ot fetoon ted? oe ,anttism ef C tettel eft To eelug -noo yderedt yretted est bas ,fetsteqo ef &-T _.ztisorte settel retmeo oft ot betoer -CTIVUOHIO AHRAIATS CMA HEDATS -tto tediate Sae reoage eft ese ew 36 .att% of tating eft to esoqtiq edt nreef oefe bas stino ~noo eta altos asatixte bss teesqe eft .yalet bestateme ets vord tadt os ,asirea mi betoer trerryo est ,fotastint et eA .yfevoenetinmte davordt ,eftoo rextrte anid fgyowWdt ebsel dteq eYslet daira eft to tostaoo Snort Hmooes edt tostaoo toort tettt .eltoo Teosqe edt dgvotdt eise1rd otam edt devordtd ,yelor tattq edt to a > -atens eftoo tetitte edt otf basorea bas ,yrettad mtem eit seefan beaolo tox et tivotto edT eit at at yalert taitg edd Bue Beacio ef Asexd 218 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY energized position, In the operation of print- ing, the first condition of the apparatus is this: the main break is closed, the print relay tongues on their back points, and con- sequently, the striker and spacer coils de- energized. Next, the print relay receives current from the distributing circuit at the same time as the rotator coils. Hence, while the rotator magnets are turning the typewheel, the print relay is drawing its armatures over to their front points, so that by the time the typewheel has been turned into the pro- per position, the circuit of the striker mag- nets has been completed and the magnets are energized. The stroke of the typewheel then occurs. The spacer magnet has, by this time, set the spacer mechanism. At the end of the typewheel stroke, the striker opens the main break, which opening clears the printer. As 8Is YHTAHDEIRT PMITHIAT TO MeTeye MUAAKOM ST »mottteog bestzrens -tnoixq to moltereqo oft mI enveareg¢s efit to nottthaos tarit edt ,act tatrq eft ,beeolo et aserd mtam edt :etdt at -no® has ,etatoq wosd ttedt wo sexanot ysfer -e6b aeffoo rsexqe hae rettyte edd ,.ylidnerpes esviessy ee taivq oft ,trell .bestatene edt te tiverto anttudiatelh edd mort trerire eftidw ,eomsH .eftos rotator eft es amit smas -feedwoqyt eft antares ers atenmneam totstior ont tevo serutsmre ett smtwerh ef yelou taitq ent emit eft yd teadt os vetntoy taroxrt thendt ot -otr oft otmt boarst meed esd Isedweqyt edt “aso texitte eft to ttrorto eit ,moktteaog teq ets etengen eft bre betelqymoo meod ead even tedt Lfeedweqyt eft to sforte ofT ,bestarernre omits ealtdt yd ,eed tenner teosce efT .etrso90 env to Bae edt JA .metnadoem teosqe oft toe stem oft aneqo rextrtea edt ,exorte Leedweqyt eA .tetnteq edt arsefo antusqo dotdw ,vserd 219 soon as the spacer magnets are de-energized, the spacing of the carriage takes place. There- fore, all parts are in their starting or in- operative positions, ready to respond to the next signal. The purpose of the print re- lay was indicated in the preceding paragraph. Its purpose is to assure an interval of time between the rotating and striking movements of the typewheel. If the striker and rotator coils were connected directly in series, in- stead of being connected as they are, the two movements would occur simultaneously, and would, thereby, prevent the correct printing of the characters. By joining the movements through the print relay, the striking does not occur until after the rotating. Having completed the explana- tion of the individual circuits used in the movements purely of a printing nature, we will now consider the distributing circuit by which these individual circuits are con- ers .Lesiateme-ob ers atengem tesesqea eft es mooe -ertedT .esaelg gexet essirreo eit to antoage edt ext ro sattrste ttedt mt ere etraq Ife ,stot 7 edt ot Brogeet ot yheor ,emottteoq evitsteqo -fenste tren -et totig oft to seogiyg edT edoargesteq sxtbeostd ane ot betsotbat saw vel emit to [evietst me erveses of at eeoqrug etl edcomevom gatvtite baa esnitsior edt nsowted rotstor has texizte eft tl .fooedweaqys edt %0 -ni ,eetres at yltoerth hetoennoo stew altoo eft ,ets yedt es betoonsos anted to bsets Bae ,yfasoonetfumte wtsrooe Si{iow efmemevom ont goitaitg goorross ead sievetg ,wdetedd S{row etnemevon eft antntot ya .etetosredo oft to ee0b antNinte edd .yefer daiva edd dasordt gottstor eit tette [fing wee ton -ensfqxe edt hetsfaqmoo antval edt mt Seas etisotto L[erbivtiat eft to mott ew ,stutan goitattg s to ylexyq etmroemevom disorfo anttudiatetbh ext tebtenoo wom I[Ilw -soo ets etivotts Leubivibat ese? dotdw ud he Ba 220 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY nected to the battery. THE PRINTER DISTRIBUTION CIR- CUIT. The distributing circuit is shown in Fig. 57; this is not the complete circuit, but only that part of the entire circuit which is concerned the the operations just described, The circuit is made up of certain contacts on the plate relays, together with jumpers which connect these contacts. The current path through the distributing circuit depends upon the setting of these contacts. In Fig. 57, those tongues and contacts which are shown without connections are not a part of the circuit now in question. Note that there are two P-5 relays, the coils of the two being connected in series, so that they act as a single instrument. The beginning of the cir- cuit is the second tongue of P-3, which tongue is permanently connected to the drum switch. oss YHUTAHDEIET DUITHIAG TO MATSYe MUHAHOM ERT eYretied sit oF Astoon -~HIO MOITUSIATeIC ANTHIRT HHT ot mwode ef jpekte guitudiatets eft .TIUO etigotto etef[qmoo edt tom ef etdt ive walt dotdw tiverto ertine oft to traq tedt ylno tad ebeditoeeh savt encttsreqo eft ext bemtsonos ef etostsoo niatiso to qu ebsm et tivoextos sdT ereqmst ditw tedveaot .eyslexr etelaq oft co tretiyve ed? .etoetnoo eset teenaoo dotdw ehoogeh ttyerts aniiudizgelrh est davordt dteq -3f% at .etostnoo esett to srtttea edt aoqu mwode ers detdw etostroo brs aergnot seodt ,Va eid to drsq ex ton eta ancttoennoo trodttw ers etect tadi eto! .nctiseno at wor tivorto gated ow? edd to eftoo edt ,evafot 3-1 owt 8 #8 ton yout tadt os ,esitee at Setoannoo -tto edt to aninatged ed? .inemurtent efuntea ergnod dotdw ,€-{ to esanot Saocee odd at tiuo -fodiwe mtb eit of betoennoo yitnenamteq et THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY Hence, when the drum switch is closed,the distributing circuit is connected to the bat- tery. Considering the distributing circuit from the standpoint of the rotators, we can make a table of those line impulses which will cause rotation of the typewheel. For this rotation to occur, the tongue of P-3 must be connected to the tongue of P-5, Such a table is given below; a negative or marking pulse indicates that the correspond- ing plate relay will be operated; a positive or spacing pulse indicates that the corres- ponding relay will be inoperative. P=3 P=2 P-1 P-4 P=5 Beh itadon: ESB ale ae er eee ME Ae Saige lier ig 221 YHIAADAIRT DUITHIAT TO METEYE MUAMAOM FHT eft,BseolIo et dottwa morBb edt codw , sone -tsed eft ot hetoannoo ef tinetto sotindiaterhb ere? anitoditxyteat&h eit antrebtanod eetotstor eft to trtogharste oft mort troorte esaluqmt ontiI ecodtT to eldest s eam mao ov -lesiweqyt sedi to mottstor sesso [fiw dotdw to esanot edd .tre90 ot mottetor etdt rot .a-% to ssanct edt of heteasnnoo of tanm §-T to eviteazen a :;wofed movis ef efdet a sore -broqestros eft stadt geteotiat oeluq snidras evittecaq s ;betsteqo ed [ftw ysfet etalq ant -seitros eft tedt ceteotint esing antosqae 10 -evitsereqont ed [ftw yeler acthaog 222 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY A comparison of the table with Fig. 57 shows that any one of the combinations of sigmi1s will produce relay settings such that the tongue of P-3 is connected to the tongue of P-5. A comparison of the table with the Mor- krum code shows that every printed character of the code (as distinguished from the oper- ating signals) is included in the combinations of the table, with the exception of the cen- ter characters, D and $. No rotation of the typewheel is desired in the printing of these characters. In the printing of the cen- ter characters, it is desired that the second tongue of P-3 be connected to the third tongue of P-5, and that P-5 be energized, so that its third tongue will lie against the front point. Tracing through Fig. 57, we find that the set-uptt++--, which is that of the center letters, produces this condition. Further- SSS YETALONINT QAITUIAT TO MATEYE MUAAHOM FHT awode Sd .att dtiw efLdet adit to moetraqmoo A eferete to esotiantdmos efi to eno yaa tedt edt jadt dove eantitee yafexr sowborq [ftw to ergnot edd ot betoenmoo ef §-I to syanrot ~roM end dttw ef{fdet oft to noetirsqmoo A .d-T tetoastedo betrtiq yrove tad? eworle eboo muir¥ -teqo oft mort bedetuanttetb ee) oboo efit to enotteantdmoo edd mt bebsfont st (alenate antts ~meo eft to aotiqesere ect citw .el{dst et to etfs to aoktetot of .° Bas C ,atetoatads tet esentd to antinixq eft of hertaeh et Lfeedweqy? -stotoatedo -meo ett to gattatig edt-al Saooes eft tadt botteeh et tt ,eretostsdo ret epanot Brtdt edt ot fete sanoo ed -1 to eradaot ted? o8 ,bestgreme od &-I teadt bas ,3-2 to troxt ast tertenes otf ftw exaaot Hatdt att tedd Bott ow SG .att davordt antoetT .tntogq roetimeo ont to tad? ef detdw ,--++44qn-tee odt -rotviot .aofttbaoo etd? ssovborq ,ersttel 223 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY more, there is no connection from the dis- tributing circuit to the rotators, so that no rotation occurs, OPERATING CIRCUITS. Having now completed the discussion of the first “class of functions, we come to the second class, viz., those which are purely opera- tive in thetr character, and require special line signals. These functions are: spacing (between words), lining, shift, backing, and rub out. Before taking up the operation of these functions, however, we must consider a new feature which the printer displays when responding to such signals. THE MAIN BREAK CONTROL. The new feature is the opening of the main break by electrical means. It will be remembered that the main break may be opened mechanically by the striker mechanism. Since the striker Ess YHIAAOGIAT OUITHIALT TO MATEYe MUAAAOM FHT -etb edt mort mottoennoo on et etredt , stom tedt og ,erotetor edt of tisotrto anttaudiat eexsono mokvatot on antveH .eTIUO#ZIO DpuITANAIC teritt edt to moteeroeth ec? Betefqmoon wor brooea att ot emoo ew ,ecottenst to aesla -~areqo ylsetuq ers dotdw ersott ,.atv .sesio Istoeqe ettspet bna ,retoatedo tfest at evit ertosas iets anottonst esedT .elseaate omit be ,gutviesd ,¢tide ,artatl ,lebrow ssewted) to sottareqo ent qu aetsiet srote® .tnyo dr sebleanoo taum ew ,revewodt ,amottonst seedt cedw eyelqetb setaitq edt dotdw errtset wen s effangte dose ot amt baoqest si? .TOMTMOS HATHA WIAM FHT i usetd stem edt to gntmeqo edt et orytset wen fetedmemer od If[iw tI .ensom [setttosle yd yilfeotnedoem bereqo od yem Heord otan edt tadt toxiate eft sont? .geinedoeam texirte edt yd 224 THE MORKRUM SYSTEM OF PRINTING TEL#GRAPHY does not operate when one of the operating signals is received, the main break must be opened by electrical means, The main break control cir- cuit is shown in Fig. 58. In this diagram, the circuit of the main break magnet leads from one side of the battery, through the break itself, through the front contacts of the min break relay, through the current limiting resistance, through the main break magnet to ground, and thence to battery. When the main break magnet is energized, the min break is open; when the main break magnet is de-energized, as it normally is, the break is cloeed. In the utilization of the cir- cuit, the main break magnet and main break ge- lay are at first not energized. The coils of the relay are connected in series with what- &SS YETAROM IST QUITHIAL FO Mareye MUAZHOM SET goitateqo edt to emo medw eiatsqo som aeob ed teum xserd mctem oft ,bevteset st slengte -ensem [aotrtoefs yd henedo -tio Lortcoo Xserd often od? etieargetb ett mI .8@ .gfl at mwode et tise ebaolt tonsa destd atem edt 16 tisgorto ont edt davordt ,yrvettad eft to ebte eno mort to ateatnoo snort edt daqvordt ,tleett daerd toetrse eft davordt ,yale1 wsetd otar odt Aaserd atem edt dgvotdt oonstetesr untitinil£ con? .ytettead otf sorsdt boe ,havorg of Jongem otam eft ,besitzveno eat temssm xserd atem oft tensean Heord mtenm ont medw jnogo ef Asetd ¥re1rd eft ,et uflemrom tf es ,bostoteme-eb st -beeolo ef -tto edd to ackiestitts edt of -es deerd atsm bas torasm deoerd ateam edd ,tixvo to eftoo efT .besinrene fon tert? ts ots yal -tadw dtiv eeivtes of besoennoo sts yeler ot 225 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY ever printer function is being used. Then, when the current for the function appears, it not only energizes the functional magnets, but energizes the relay coils as well. The relay then picks-up, as is shown in the fig- ure. This position of the relay completes the current path from the battery to the main break coils, and the main break opens, The reason for using the main break relay to control the break, instead of connecting the coils of the break itself into circuit of the function, is to insure the complete operation of the function before the opening of the main break. THE SPACING CIRCUIT. The spacing circuit is shown in Fig. 59. This is the circuit utilized when a space signal is received over the line, usually between words. The spacing is performed in exactly YHIARORIGT DUITMILT YO MATCYe MUSAAOM FHT ~sent..beay uited ef nottonyt retnitq teve eetecgae moltonut edt rect tneruro edt aedw -etenasm [anottonst odt assisteme ylmo vom tf edt .ffew ea eftoo yelor eat eesterene tud -ait sft of mwode at es ,qu-adotq nent yelor eetelfqmoo yefer oft to gottteog efdT . et wisn eft ot yrotiad eit mort dteq taneris0e edt .2tego Aserd otem edt baa ,efloo aserd otem eft antes tot nosset eft to bastant ,deerd efit Lortooo ot yelot weord otat tfaatt Heerd oft to altoo end noktoennos eit exceant of et ,noktonut edt to ¢isorto esroted soitonut odt to nottsireqo etefqmoo -Xserd atem edt To goineqo sat efT .TIVOHIO ouIoOsTe FHT etd? .@8 .atl at owode et tivorto gotosqe {enete eoaqe e sedw bestiftes tinorto edt at mceewted ylilaves ,entl edt tevo hevtessr ef Yistosxe at hesrrotisq et aotoege ofT .ebtow THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY the same way as it is in the printing of let- ters, except that in this case, no printing action accompanies the spacing movement. As is indicated in the figure, the circuit re- eeives current from the distributing circuit at the third back contact of P-5, From this point, the current path leads through the space coils, through the second back contact of the print relay, through the coils of the shift release relay, then through the main break relay to ground. Hence, when the space signal is received, upon the closing of the drum switch, the space coils, shift release, and relay coils are energized simultaneously. The remainder of the main break circuit is the same as that just described. It might be added that the print relay is in its in- operative position, since there is no rota- tion of the typewheel. Note that the space 226 YHIARDSIST DUITHINI TO MATLYS MUAAAOM FHT -tefl Yo umtiotty edt at ef tr as Yew omse odt anttaicrq om ,eeso efit at tant tqeore ,etet eh ,toremevom antosce et setnsqmooos acttos -et throrto edt ,ervatt sit ot beteothat ef tinette gattudtatarb edt movt trerrze eevtee etdit mort ,d-T to tostnco Xosd bridt odt ts efit devorctt ebael dtsy trertrse edt ,tntog tostmos Yoad hbroose od? davord? ,altoo esaqe edv to eftoo edt davoxrdsd ,yefor tatraq edt to otem eft davoxrdd met ,velor sesefor tttde eoeq2 eft cedw ,comel .bevorg ot yeflet zaord edt to antaclo eft moqy ,bevteser at [anute eeselsex Sitde ,eftoo esseqe sit ,dotiwe mrrh -yLesoonetiumte bestarene ers eftoo yefer bas et tivorio sisord atem eft to tsbotamer efT tdatm ti .bedivroreb text tert es emes ott -nt ett aft ef yefer taixrg odt teadt behibs ed -sgor om at eredt sonts ,rmottiteog evitsreqo eoagge eft tant efoll .feentweqys edd to nott 227 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY signal not only causes a spacing action, but also releases the carriage from the shift position, providing, of course, that the car- riage was in that position. THE LINING CIRCUIT. The cir- cuit of the lining magnet is shown in Fig, 60. The battery current is received from the distributing circuit at the second front con- tact of P-5. From this point, the current path leads through the lining magnet, through the coils of the main break relay, and thence to ground. The main break and relay circuit is the same as the one previously described. THE BACKING CIRCUIT. The circuit of the backing magnet is shown in Fig. 61. The circuit receives energy at the fourth front contact of P-5, From this point, the circuit leads to ground through the coils of the backing, release, and main break mag- ¥Ss YHITAROEIST OQUITAIRI TO MATEYe MUAAHOM FHT ted ,cottoe antoeqs se seasso yino ton Iaonte ttic¢e edd mort saetares eft eeemeler coals -t20 odt tadd ,satsoo to ,antéivorq ,coftstieog scttteog stadt at asw ogett etto eft .TIVONIO OSuIUIL XET e2tT at mwode ef tenzuem antatl eft to sino edt mort Bbevitooer at tnerrvo yrettad edT .0a -109 tnort bnooos edt ta tiseonrto gotbiedizrteldS tnettioe eft ,tatoq efdt mott .a-f to toast dasowlsd .tensem guict£l edt danord? efeel Ataq sonmedt foe ,yslert aeotd atam ot To eltoo edt ttrorte yefet bre xe0erd ntem ed? .hoavota of -bedirceeed ylevotverq eno eft ee emsse edt eat ent eTIUOAIS PUIMOLA THT at awode et tensem anivosd edt to tiuotto est ts vyatrene aovisset tivetto ed? .fd «att eettog eidt motl .a-2 to tostmoo daort dtiot eftoo ett davords bavora ot ehsel tivetio edt -sam Hserd otam bus ,essefet ,anidesd sdt to oe THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY nets. Hence, the release (shift) and main break coils receive current simultaneously with the backing coils. The control of the main break through a relay is not necessary in the case of the backing mechanism, since only a momentary energizing of the backing coils is necessary: the mechanical lock on the backer holds the parts in the operative position after they have once been placed there by the backing magnet. Hence, the main break is placed directly in series with the backer coils. THE SHIFT CIRCUITS. Next in the order of treatm nt comes the circuit of the shift magnets. However, there are some special requirements of this cireuit which should be explained before the discussion of the circuit itself is begun. The first requirement of the 228 YETARDEIRT YAITUIAI FO MSTeYe MUAAAHOM FHT atem Poe (tttdea) eraser eft ,eoned .aten yfesoonstiumte tnerxyye eviseset e{too Asetd eit to Lorénoo eAT .aeltoco urtdesd eff dttw YTBaLeoen tor at yafer sa dsxordt aeerd actam somte me tredtoen anitvcad eft to eeao ot at aniveosd oft to grtstarene yretosmom = yino mo XoolL Leoinedoem ett iyrsseecen ef aftoo eviteteqo edt at etrsq ont ebfod texosd et heersta deed somo evad yest rette nofiteoq ataw eft ,gonel .tenaem aotioad edt yd etedt edt dtivw eetree ot yltoertb beoerslq at xserd -aftoo rexosd txel. .eTIUSAIO TaTHa FHT tiuexrto eft eemoo tnantsett To tebro edt ai emoe ets etedd .revewor .etemszem sttde ent to aotdw tivorto eftdd to ednomeriuper Iatosge noteausoeth eit eroted bentelfaxse od biwode emused et tfLeett tisorto edt to edt to tremettyper tert? oT THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY shift magnets is, of course, that they nor- mally carry no current, and that they remain in that condition until a shift signal is received, Upon the reception of this signal, the shift magnets should operate the shift mechanism and clear the printer by opening the main break. So far, the action is just the same as the other functions. However, the shift magnet should lock itself in po- sition, so as not to be de-energized until @ release signal is received from the trans- mitting station. In other words, the locking current must not come through the main break, but must come through the contacts of the release magnets. These requirements are ful- filled by the shift circuit. The shift circuit is present- ed in Fig. 62, which shows the apparatus in its normal, or inoperative, position. The cireuit receives current through the distrib- 229 ess YALARVELET DQUITUIAG TO METEYS MUAXHOM FHT -rom yodd tedt ,setyoo to ,at eaetemgem titde mtamet yedt gedt fos ,jnetiuss om yriso yiisn at f[ansta tttde se [ttoay nottticos tad? at efenate eit to nottqssst et moq’ .bevteser ttide est eteateqo bisode etonznam ttide sdt goineqo yd tetnixa edt taefo bas matnsdoom tent et mottos sit ,ret of .tserd otem oft ,TEeVewoH ,encitonst redto ext es emsa ect -o¢ at tiestt fool bi{roda tongem ditide est fttas bestgterce-eb ed ot tom as oa ,aolttis -enett eft mort berteset et Langte saselet e gatdool edt ,cbrow redto ot .notvate gaittin eHsetd mtam eft davordd emoo tom term tne1t1s9 est to etostnoo oft dasotdt emoo tensm tod ~{ut ore atnenertizpet osed? .atengam sesoelet etiverio tttdea edt yd Bbelfit -tneesrq ef tivyerto ttide eAT . ot extetsqas eft ewote dotdw .$8 watt mt be edt .mottieog ,evitsteqont ro ,fsorrom ett -dixtetb edt dgvord? tretas9 sevieset tisotto 230 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY uting circuit, being connected to that oir- cuit at the second back point of P-5, From here, the current path leads through the left back contact of the shift relay, and then through the relay coils to ground. The re- lay also acts as the operating solenoid for the shift mechanism. While the shift relay is operating, it first closes its second front contact, and then opens the first back con- tact; this latter opening cuts the relay coils off from the distributing circuit. However, the closing of the second front contact com- pletes a second current path to the battery, this path leading through the back contact of the release relay. Hence, the shift re- lay has operated and locked itself in the operative position. At the same time, the relay has closed its first front contact, which A YHTAAOSIAT DUITHIAI TO MATEY MUAXAHOM FHT -tlo gadt of betosnnos antead ,tinetto antiy mort .d-2 to gmtoq Hoad brosea edt ta tlio ttef ext davordd absel diag tnettv0o edt ,etsd neat bas ,ystet ttide oft To tontmoo Aoad -ert ent .bosota ot eftoo yslert edt dacotdt sot hionefor anitesteqo edt es etoz oels ysl yefer titdea eft elftd! .metnedoom tide edt tnort Broose ett sesofo terlt TL ,gntitsteqo ef -coo Mosd tgertt oft aneqo medt bre ,toataos eftoo yefor eft etuo antaeco tettal etd? ,tost etTevewol .tinvorts anttiodittetbh edt moxt to -yoo fostnoos taort Broces edt to anteolo edt wretised edt of dteaq tnexaso Baooces vs eetela toatroo Yosd edt davoirdt ant beef dtaq elds -et Utide eit ,eoneH .yalet eesefer oifé to edd mt tleett hexool ins heteteqo ead yal etoftfaoq svitareqo velet oft ,omtt omse oft tA , doftdw ,tostmoo taort farit att boeofo aad 231 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY closing supplies current to the main break magnet. The break therefore opens and clears the printer. However, the opening of the main break does not open the locking circuit of the shift relay; hence, that relay remains energized, and holds the typewheel in its shift position. The release of the shift re- lay is effected by the operation of the re- lease relay. This reley becomes energized when a spacing or backing signal is received over the line. THE RUB-OUT CIRCUIT. The rub- out circuit is shown in Fig. 63. The battery is connected, through the distributor circuit, to the fourth back point of P-5. From here, the circuit leads through the main break re- sistance and main break coils to ground. Hence, when a rub-out signal is received, it oper- ates the main break, and thereby clears the féS3 YHTAAVRIET DUITMIS TO MUTCYe MUSAROM ANT wserd atem eft of tausrtwo eetiqqve amteofo aresfo Sue exeqo eroteisdt teerd ofl .tenagem atam edt to aatnesqo edt ,revewoH .tetatrq edt to thyotto antdool eft asqo tom aesoh daetd antemer yalet ted? ,soned i:ysfer wtide eft ttide att at [seriweqyt edt ebfod Sne ,Sextatrene emottteog -et Stida edt to serzefer siiT | -et oft to mottstrego odt yd betostte at ysl hestateas wemooed yefer etd? .ysafler sasel bevtooet et Ieaate gxtNosd to antorqe e nedw -ontt eft revo -dyy edt ,TIVOAID TUO-SUH FHT ytotted edi? .Sd .ati at awors at tisorte tso etiootto totsdirtetS edd davord? ,betoenmoo at ~oted motd .8-I to tmtoq toed dtavet ont ot ~9t Xserd atam edt davotdt ebeel tkyorto edt .oomeH .hasorg ot elton Haetd atam boa goustste -tego Tr ,5evteoet et L[anagte tvo-dyt s nxedw edt atsefo ydetedt base ,daerd mtam edt asta 232 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY printer. THE DISTRIBUTING CIRCUIT. Having completed the cireuits of the indi- vidual functions, we will now study the dis- tributor system by which these circuits are connected to the battery. The complete dis- tributor circuit is presented in Fig. 64. It is here shown in the inoperative condi- tion,which condition it retains if a rub- out signal is received; any other signal chang- es the connections. That part of the circuit directly concerned with the printing of char- acters has already been discussed; we are now concerned with the circuit from the standpoint of the purely operating functions. There are two requirements of the distributor circuit in this connec- tion, viz., first, it must connect the bat- tery to the beginning of the individual cir- cuits, and second, it must never connect the ww oO 9] YHIAAORIAT DEITHIAL TO METSYS MUAAHOM HT -totatrg eTIVOAIO OMITVAIATSIAC FAT -tiat edt to sttwotts edt beteliqmoo antvsl -~elh eft ybsta won {fiw ow ,agottonst [avbtv era attyserto eeedt dSotdw yd metaye totudtiat -3f5 etolqmoo edt .yrettad edt ot betoonnoo 33d .ott at betmesetq et tiveorts totudixt -thnoo evistsatsqont eft at mvoda oted et tI -duy gs tt estster tt motttbaoo dotdw,nott -gnado [erate tedto uns ;Sevteset at I[angte tuo Stuotto edt to traq tad? .anmottoonnoo edt es -tado to anttnirq edt dttw bemresmoo y[toorth wor ers ow ;bssesoatbh seed vyheetfs esd aretos tatogbuaete edt mort tiwerto edt cit fw berteomoo -emottonut actkteatoqo ylerg edt to etnemertuper owt era stedT -oommoo etdt af tivorte totudiztertS edt To -tad edt toonnoo teum ¢f ,tertt ,.siv ,aott -tto favhivthat edd to zaturtsed edt of ere? edt toennoo teven tanum tt ,fooosa haa ,ative 233 THE MORKRUM SYSTEM OF PRINTING TELEGRAPHY battery to the rotator circuits upon the re- ception of an operating signal. If the rota- tor and center-letter circuits do not carry current, the print relay will not operate, and there will be no printing action on the part of the machine. The following table shews what combinations of current pulses allow of these requirements. P=3 P-2 P-1 P-4 P-5 + + + ge ee ne = ee) CE An examination of the code shows that every operating signal comes under one of these classifications. &ES YHIAADSINT DUITHIAI TO METeYe MUANHOM FHT -9t edt moans ativetits totetor eit of “rotted ~stor edt til .fangte sattesteqo as to noftqes wrreo tom ob ettsetteo tettel[-1retmeo bas tot ~eteaereqo ton {[[fIw ysfot taxitq edt ,daetrs9 edt mo mottos antiatitq on od [ftw etedd bre -enidoan ed? to dreq ewote eldst satwolfot aT wolls seelyug taesrrus to emotteantdmos tady .atnomerisosr seedt to a-f deT £[-f $-T B-T yvrove tadt everd2e shoo sdt to no ttantmexe oA eaedt to eno tehas semoo Lanrgte sattereco eanotteaeottiecalo fa PO ZL N/ bao PUMA POWAY oY e (b/ 4VIHUND () Impulse Diagram, Plate I - Perforator. Plate II - Ferforator. , i ag f if Plate III - Distributor Plate IV - Distributor. Plate V - Distributor. Plate VI - Distributor. Plate - VII - Wheatstone Differential Relay. Plate VIII - Wheatstone Differential Relay Plate IX - Printer. Plate K - Printer. GAR: D ae a ay SAR iNet 7 ay i At Ae i nh nis ih a inte ne i Plate XI - The Printer. Plate XII - The Printer, ae iF Wh ri ne inf Th ih a '" Mes, oh i ie , ; it me j Y a yy | n Ray i) ee iy M ny = — sy ae i rR Ra TAPANS UT TING STATION As. /. pours TRANSIT TING STATION ; NECEWING STATION oY | a 1} | | te a Fete) Puc | Cmane a Aenea fee cas ; re Z | \- as Unley ea SRMCING lg MARBLING 4 +f i) - = 2. Ly dao ‘al ee ‘ i ° AN SMUT FING STATION ZoN\ 6 NECEWING STATION Aare * ef FG. 4. - | ” Na ; ail a eee a a Sis fh Lak i i t \"h eye 4 a tie be } i si AN ay, f j rey Ai 1 { , . f ’ ‘ i By + j i ie! 2 } ; hy 2) at hasten Ge ee 2 i vet ioe } rar { i i i b - “ } A ; ' . i \ « ¥ ( \ , i , f " ney i . n ‘ , i { } at Pir iy i i ean oy il Y ing K aE A, S f i n 1 el v be a human vt ae hf ae ae ‘ ay Me ea i} haya i are ee - yu PUN LIME BATTERY ite ee = TRANSAT TING STATION MECEWING STATION & a ty 716. o — , are ih tee HI ny ] ND j # une und . he 6)" fi a atl Wii , 4 vin he WA » bis (A) f ‘) MET RAC MAGNE FEF we ATC. ‘ 4 1 : i J y \ mt) i) at \ Rihaly lah tah in ; iia? rl al f M4 t : him Ay, j ye es Ale a tit i} Pe i 4 ‘ i Ant 4 ty ipl Hl rr 5 AV \y fy at ; ty e ae \ Nite BoM hy 1G. 1 heh haar ait) ae TR Bacw Space © coven y - ‘onl SOME TN LP 2EvER Ga (abERP Pinion f ff Conrser SHawelé Puteo Con mater Panr ‘foro “76./6 = Goverenonr LLM Fat Orin Scie es Bi) | Sw a) Ee Sy ee ae Oe ee re eo ee Oe le MN a AN ei ts lla te WAL SP MAAN LINE if VPRANSA/TTING OSA 5 G25 { LAMP SiG- WAL BREAK Aek + Or. 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At Lae ¥ \ iy pe 1 ee aad a AON id | Los Tv i i > \ i Oth na sis Pay ; +h m AT A a ; i we SS .