‘The Davisson Cathode Ray Television Tube Using Deflection Modulation Dy ALG. JENSEN lakers Ha bi wn crnazed by Be CN Bae HE present day cosa cable roa! Band ranuminson aysten wa develop ering the ely 188 x ws eigally ooncsva as ‘metas for multi-channel telephone trssmission, During the sme periad the rapidly developing television ast wae prndcing video sigale roping, wwiler and wider frequenry ands We ear very sonn vealed, therefore, {at This cousa system wold ler el acral tn ve Cans ef such wide band television signals. Tae ely deve'apment culpa fn the installation of «conan cable route fin New York to Palade. ‘Tain aye wan desig to pve 40 Ween chance oF 9 ingle 200 ke Wlevision chante nd hath types of tans. wer succstlly seemed drng ae of donation 472 The waning cipmest used ‘oe puoducing the television signals fo: these denna wna dovelapod under the divtton of Dr HE. oes sa the Ball Telphone Taboratories, It we designe! to san sista ‘85mm mation pietare lm an conte of asx foe ste disk rotating at 10 apm and having 20 lees nase roo te petiphery. Te ts truce elvis al of 240 Tne ao 2 Fares, ooo ga badd of about 80 kloeyeles, "Fr Wis save pei cane the well Enowa work of Dr. Davison inthe Gehl of electnasdifecction® Tis work had seule alzo ia important sdvances in electron optics ad inthe develepzent ofthe aarp Fosse, ell defined electron bet. Te was natural, thezfors, that Dr. [ves chou cuss with Dr, Daviston the possbity of designing a cathode ray tube ‘ule of slate igpaying pete frm theLelevion squat Sel above. The trom of the conte ns tek Dr Davison, th the cove and able collaboration af C.J. Cubic aaderunk to design aad farsract the abe deere! inthe follwing yes Ts this conection it tho alo be mentioned that he Set experimental ame af the tae ‘were built by GH, Reiter mile the [ater engineering for Emsited produc iow as cari ont by H.W. Weinhar “The disk scanner was & near ransmiier co the plimle of Ce goal toa cre tly qe] tothe flan Teghenes. "Ta fume] oqutement for ening ‘abe tae therfore as tated by Dx. Davison Ian ex'y memoreadum TS erm il ae proportional to Beam current or mms sees Se tw Inn cunt i t2e rev tae shot be ropes] to ge rel voltage; te dations of Iran eusrent by sgval wllage should Be liner, Flare tu nee his reqrement eis in elsicaiov nf ne values Sn repeavetton, aed hen degsetures ener are marked ft Jad to nstilactony plesurcs 1 was this fondmemal rome. af a eam corene deel proportion to fut wise, wich ed Inthe develcpaent af 9 take employing dedee- toe modoletion, ive i type of tedulstion in which the maing Waltage causes the el tron kez to be defeted sero» defining serio jn sech a manrer That inrvarng mounting voltage wil cause a leper fice te bers tops hnoagh te apr ad theres he eight tess of te seeen pronoatianedy tothe meron voltae The pace OF tis ty nf moat ie satated in Fi Figure (a) shows a erie ir if eletrns pasig trough the sit S (perventcue to the plaae of the peer) and aeranged to form & shexp ine nf the sli the plane of the sseare aperture 5 The relation of the tie mage to the square apron ison i Fi. (8), A bie voltage i pled esis the modular ples Wy wd AP 0 chat the ait imege fls ssf the syuatespartare for no sgn voage. As signal velege > mp pied aero the madtlstor plate the si age will ive seoss the npet= Ture sich a mange tht the reser ael atc of the beam beyond he sri propeaioaa to sgl velage (for email! engies of detection, ss ede), ravistor cxrmanr way TeuRVIEN FoR sr Leyond she aperace the electron Yeas enters projet las 5y- tem eesignat to prject neve ston nage of tthe res sent screen ofthe ‘tbe, Tn order to toil further moan of te bey | ; L aes in the pgm fens sytem tf eget that the Beas be mnataine mall id. ie tube ins fad ot be deleted ye mation as a Fig 1M}, Ta secomplich she second pat af muting plate 8 and AFL avis CATMODY RAY TEERUIION TORE 350 in add an cn connected wo At und 3,3 indicted ia Tig. 12. Now sen sgoalwolage i paid, the rleetnon nem ieinlane, vather Ua Alefected, acroae the spertine ae the porn uf Une hese etorag the Projection lene syste is maintain ia proper clguaont with tho tube "The cma set ronuptcal system of the tbe is indicated echemt tally n Fig 2,8 dimensional coe section of the tube ie shown in Fig. 3, hile Figs, nd S show rechaniesl deal Ube asl. igure 6 the tne tate, held By Me. Calc, Refering to Fig 2, he pes, PS, 2,20 and PY are metallially ‘connected tgetier with separating metallic eyes to form the stat tural “lane” ofthe etic letra serombly, They are eonnested to the internal Aqatdeg coating tnd hed at grow pleat ‘The backing pte 7, ment F, ad elmaar aperture platen P, and Pe constitste the electron course and condensing lens eprom aoe Faneton “Pes muy eh singe nt wision exon way seems FORE sot |S to peoduue ae intense “oc sp of electrons ia the ple of the ait aperre 5 (Fig. 1, ‘The Hlameat Fis made of tungsten fll nthe shape of «cross (Fig. 3) tnd fed by divectcuevour with opposite ead of Ch cross connected to- feces, This costcucioningures 2 nearly fon lemperature over Ue ‘nce aren uf the eros analy ninimdaen reagete ele ae up by the Fumes carant, which woald other tend to dru the eecton opt fal ssinetey- ie Hemestcestance te apnicnaely 1 lem al he eae eat IO expete. The hip caisson cueeat devaly om 2 tungsten Ea rent mas exported to eet in 8 more nee Toel spot then ould be Dnucrahie wth anomie ested etre. Alun ohe arge metalic stactne invite the tebe sight tend to comee devetivition or peeoning ofan ie rath 1 ie mecianiea alignment were perfect the “Yoca spo of electrons ‘woul ll directly on the ait aperture. Hecause of unavoidable small mise Migueacate eal particularly due lo the fact that Une Samant ras ib wot Peet fat such perfect symmetry cannot Le insured without some cor ctions These eotections exe supplied by ¢ socalled collimating unit Ch. 0. Phe anit conse of em slecrragnot with ingle pele per (hig. yan by appy'ng mal coring voltages ad curren he the “foal pt ete ei is rt rena: fal Ue tater pation of the at epertce S.A sacra identical colinsting unit (CPs Cos is mounted ater the vi, i oder to ceutr che ait image on the quae apeetare 8. ‘The thee csc aperture place PS, Pend Py constitute the socalled tuoduletr lens system and serve to fora ga electron image ofthe ait 5 fon th square epercureS with a mogninestion ef I. Accurate focussing iemptsnst hy ost the peal the pte Pa ‘The action of the daar plates MyM aad MaRS ha ley beow osered. The photograph in Fig 4 stows the modulator pete assembly ‘The sot of thee cieulae apertare plates F2", Py and PY comprise the jens len yet, hich form a lei ing of the equate apee- ure s* upon tie duoteeson seeen with a mayaikension of S'1, Proper focussing accompli ed by adjstig the paent of pace "ro cea of el azsun‘es in the Inceal comers af tae tube ovsing, sven fo teste the eth’ el ach predates il dete or rangle sf 4° from the erties andy hy prover aesting the ol “aor pb to pmdae practialyaniform magelic El, ih ‘eosin Inlet hen he sen Tecan wf he rorsplcael mechanical say Snide ele there vas orginally come difcaty in propery degusing the tubes and ene Taina vaemen. Phe euler roel wer Une emtinucsly pun, Dnswisow @ARMOn? kay sLEvRION TORR mss ‘nd a oto Slamert manomator waa usd for checking preture. The tebes used during deniastatios were sealed ul, bot the mromeer was retained as own a he photograph in Fig. 6 Tr ace the hot tata, fnment acted a8 a getter which aucosllly Kept the presare down to boat 10° min He The apetuie 5 was 6? square, With 2:1 mnglcation tis rested inn seunnog ine height on the seen eoecsponding to 4210 line pice of shost 7 8 ines A stationary spot viewed on the sercen stow shaxply deta settan ular erenaoetion of approximate srfom, Drightaes, Adjusted for no ig. 7-Seenat dee af node curve overlap thi resulted nat eld th only fine cation of ln ste tore. I the ime of the st falling on the aquare sperture Sis prtectly focussed, with eeges peal! to the ides a the aperane if ro stray ee trons ate present duo to secanlteyerviion or ober ease, and te ‘leeteons i the bet al: have the sume thar} emission energy, then the ‘arve of beam cutent yeraus tclatorvultoge wld be ne sow’ a Tie 7. The curse veo unt the lading ee of he ai enters the sper fore The corm then incest i trees a ints when the lt ile the spectre, Ifthe alt wider thin he apertare the carve vel have a Bat lp and il Chen decrease Tneriy ag the tralng edge of the alt waves cro the apace ‘The setae! mulation erve dd not show shacp corners, bat was rounded both abi an bottom a cated the dnt ines ia Bg 7. ‘The dispersion of thermal velocity of the electrons cnoes “chromate” aleration of the condensing lens wstem (Py; P) wich therfore fms 8 66 emt. svstn HFEMMEAE JOURNAL, CeTUME 1981 “Socal epot of non-eiform denny This in ton rests in ror wid vores sf Cre tmaluation cane Eves, the near portion ofthe ipdulton eve ‘urrpnlel tory eure ratio a abou 101. Sa wil be seen Srom the curve, the tbo maybe ee cpaly we for cither postive or negative moduli, bt inthe éeonalins pve duo wae employed ‘An actual modulation curve for the teller wl for 4 ive pictues fs shown in Fig. 8, The dotted line fnicaes the maton heaters Tithout aay iiodifcation, mle tae sok carve show Ure improveeneat “TTL! vA att | ear eutof eblened by inconporsting w non-fnane rel ia he oatpat age othe video ampitr. Wily his exit, Finest moulin as ob Tail over a bgxtnese range nearly 10021 ‘Due tothe veresle with of ee acunnng spol i obvlous eat con ventions! apertae equalisation & not appli. The wile of she rectan ler spt cages from rasan &¢ fa brighlnees to sexo or rr n> Er the decp shade ln oer wore, the ert apature equalization trould bea aneton of Inghtiese, Some chemical eonpatatonsideated {hac the efectivehorinstal teoivtion, without eay aperiore msalzadon, tnigit be nell ahove the verte! rsaiow detennined by 220 ins. That this woe ecualy ses iaiened Hythe fet shat, by arbi ie