commercial

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place two simultan

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screen: the Intensifie

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doing just one

to do it well.

* Allen B. Du Mont--cathode-ray pioneer and specialist-examiningone of his earlier 5-inch teletrons. Back in 1931 Du Mont virtually wentinto the seclusion of his home laboratory for the purpose of studyingcathode-ray oscillography and working out a commercial solution ofthe cathode-ray tube, which, up till then, had been a rare laboratorycuriosity. In the succeeding years he evolved commercially practicalcathode-ray tubes, oscillographs and associated equipment which arein use throughout the world today. It is this man's work, his associates,his organization and his contributions to the cathode-ray and televisionarts that constitute the unusual story that follows.

CATHODE ..RA Y a,nJTELEVISION ARTS

Jhi6 is the story of the first decade ofthe Allen B. Du Mont Laboratories. Like-wise is it a vital chapter in the generalhistory of cathode-ray technique and itsdirect offshoot, the present-day televisionart, for the Du Mont name and the cathode-ray practice are inseparably linked together.Mention of one immediately brings theother to mind, and thus is appropriatelyreflected a fruitful ten years of pioneering,engineering development and productioneffort without which the cathode-ray tubemight still be a laboratory curiosity, whiletelevision could hardly rate in commercialterms.And so we enter upon a most unusual

story of a man with an idea which devel-oped into a specialized organization pro-ducing cathode-ray equipment used through-out the world, which in turn has laid thepractical foundation for successful tele-VISIOn.

THE MAN WITH THE IDEA

The activities and achievements aboutto be discussed begin with Allen B. DuMont, the man with the original idea. Infact, the organization bearing his name issimply an extension, elaboration or justplain multiplication of this man's invel1'tive genius, engineering skill and drivingeffort. The Allen B. Du Mont Laborato-ries today enjoy a multiple function, servingat once as an engineering and developmentgroup, a patent-holding company acting aslicensors, a production plant for cathode-ray tuhes and equipment as well as tele-

vision transmitters and receivers, and againas a television broadcasting system readyto take its place in the field of video enter-tainment. But to get to the beginning ofour story . . .Back in 1931 Allen B. Du Mont con-

ceived the idea of commercializing thecathode-ray tube and exploiting to thefullest the many possibilities of this amazingdevice in everyday work. At the time thecathode-ray tube was a laboratory curiosity.Prohibitive in cost, its use was limited toa handful of laboratories working withlavish budgets. To think of the cathode-ray oscillograph as a commonplace tool inindustry, such as it is today, was simplyfantastic and even preposterous. But notso, perhaps, when you appraise the extra-ordinary background brought to bear onthe problem by this man Du Mont.Born in 1901, in Brooklyn, N. Y, Du

Mont had served as a commercial radiooperator on coastwise and transatlanticships. He had owned and operated ama-teur transmitting station W2A YR. Latercame his graduation from Rensselaer Poly-technic Institute with an electrical engi-neering degree, followed by several yearswith the Westinghouse Lamp Company,first as engineer in the development labora-tory, later as engineer in charge of varioustypes of radio receiving tubes. While withWestinghouse he applied for numerouspatents covering tube improvements andtube-production equipment. One of thesepatents made tube history as a high-speedautomatic aging and testing machine' opel'-

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tit- The Electron Intensifier e Illustrated above serves to accelerate the bemn subsequent todeflection. The use of this electrode permits greater brilliance with a giVen deflection sensitivIty.or increased deflecti.on sensitivity for a fixed value of intensity.

Just wI"" ;5 u cllth.ode-m)' II/he? 1'1,;5 grell,l)' reduced reproduction of a two-color wlIllclwrt i.ssued s€r,eral ycars °0° IJy tIle Du Mont organi.':.(dion to Scl100ls, engineeringdepurlnwnts, [a[,orotories (JIlll (li/ier institutions, first made common I~nowledge out of tl-Iecrstw/lile "Iyslel"ips of t/lis 1/('''' art.

ating at the rate of 5000 tubes per hour.For this and other contributions he waspresented in 1927 with the First Award forthe most outstanding accomplishment ofany employee in the Westinghouse organi-zation.From Westinghouse, Du Mont went to

the reorganized DeForest Radio Company,first as Chief Engineer and later as VicePresident in charge of all engineering de-velopment work and manufacturing. Therehe found an abandoned plant which hadnot been operated for over a year. Theavailable equipment was obsolete. The DVsenes of audions had already been super-seded by improved tubes during the com-pany's long inactivity. There was no per-sonnel on hand. Nevertheless ...Within a few months Du Mont had

gathered new machinery, trained new per-sonnel and was turning out in excess of30,000 receiving tubes each day. He de-

veloped much special equipment to speedup production and reduce costs, includingthe improved high-speed sealing machine,automatic grid winding and welding ma-chine, high· speed base-branding machine,high-speed basing and wire-cutting ma-chine, improved weld machine, high-speedautomatic seasoning and testing machine,and various tube-characteristic test sets andlife racks.Du Mont then turned his attention to

transmitting tubes. Soon a complete line oftransmitting tubes was made available. Latercame the designing and building of 'phoneand code transmitters from 50 watts to10 kilowatts. Under his supervision a prac-tical facsimile system was evolved.With the absorption of the Jenkins tele-

vision interests by the DeForest organiza-tion, Du Mont was placed in direct super-vision of the DeForest television develop-ments. This work was climaxed by the in-

-----------------~------------------

auguration in 1930 of scheduled sight-and-sound programs over DeForest televisionstation W2XCD at Passaic, the very firstAmerican genuine television entertainmentof record, despite the limitations of 60-linemechanical scanning so apparent to DuMont.Indeed, realizing the need for cathode-

ray technique whereby to further the prog-ress of television, along with a better in-strumentation of industry generally, DuMont resigned his important post at De-Forest and went into virtual seclusion 60 asto concentrate and specialize and pioneer.Thus the extraordinary background broughtto bear on the cathode-ray-tube commercial-ization problem.

THE Du MONT ORGANIZATION

Is BORNThe year: 1931. The scene: the base-

ment, and a little later, the garage of DuMont's home in Upper Montclair, N. ].Here Du Mont set up some second-handtube-making machinery. Aided by a coupleof skilled glassblowers, he began his questof the commercialized cathode-ray tube.Du Mont made 'an exhaustive survey

and study of the cathode-ray art up tothen-literature, available tubes, knownusages, potentialities. He designed andbuilt many different types and variations.In a few months he had evolved practicalcathode-ray tubes in several sizes, and thesewere produced for sale on a glorified labo-ratory basis. They were snapped up byanxious seekers of cathode-ray equipment.So much so that the laboratory activity nowhad to be stepped up to something likecommercial production.The basement and garage space soon

outgrown, Du Mont moved his small or-ganization to a store in t,own. A few moremonths and a hole was knocked through thewall, taking over the adjacent store. Thenanother hole and a third store, anotherhole and another hole, until five stores werejoined together for a Topsy-style productionplant and engineering laboratory. Crowded,awkward, uncomfortable from the heat of-------~.----_.

many gas flames and molten glass, the quar-ters were by now inadequate for thesteadily mounting output of cathode-raytubes and even complete oscillographswhich, heretofore made on contract by out-siders, were now Du Mont produced.

A PLANT OF ITs OWN

And so the Du Mont organization, nowwell beyond adolescence, moved into itspresent plant building purchased early in1938, located on the outskirts of Passaicand with ample grounds for future expan-sion. Here with over 30,000 square feet offloor space, and with 'a personnel close totwo hundred, the Du Mont organizationalready finds itself cramped for space bya business that has exceeded the fondest ex-pectations. Particularly in these days ofNational Defense activities, when Du Montis called upon to produce radio communi-cation equipment over and above thecathode-ray equipment required by manydifferent industries, universities, laborato-

To produce the giant teletrons. special exhaustpositions and ovens had to be built and in-stalled in the Du Mont plant, TI,e aluminumcylinders contain heating elements which heattI,e gloss bulbs and drive out moisture. duringpumping operations.

ries. An annex has been obtained close tothe main plant, and additional personnelis now at work on Government contracts.And all the while this man Du Mont is

the directing genius. He works incessantlywith his engineer-specialists. He checks,suggests, collaborates, in the design of newcathode-ray tubes and equipment. He is inclose touch with production activities. Hetakes a keen interest in the sales and busi-ness functions of his growing organization.Engineer, inventor, production man, prac-tical businessman-we have here that rarecombination of the many elements neededto weld the growing band of specialiststogether.

From June of 1931 until January of1932, Du Mont designed, made and testedmany experimental types of cathode-raytubes, finally evolving the broad basis forthe electrostatic deflection tubes now ingeneral use throughout the world in the3-inch, 5'-inch and 9-inch sizes, for oscillo-graph and allied purposes.The Du Mont organization has simpli-

fied the general design and production tech-nique, whereby the cathode-ray tube, oncea laboratory curiosity and indeed a rarity,has become commonplace equipment. DuMont has pioneered the high-vacuum typewith two sets of electrostatic deflection

plates. After a decade of specialized ex-perience, Du Mont engineers are confidentthat electrostatic deflection is more satis-factory, which point is generally conceded.Due to distortion introduced by the in-ductance of magnetic deflecting circuits,as well as the presence of negative ioncomponents of the cathode-ray beam whichare not deflected magnetically c.s they areelectrostatically, electrostatic deflection issuperior not only for oscillographic butalso for many television applications.Coupled with electrostatic deflection, Du

Mont engineers have worked for a fine uni-form trace, high intensity, high sensitivityand exceptionally long life. Intensive studiesof various screen materials has resulted in achoice of medium-persistence green (for theusual run of work); short-persistence blue(for an actinic blue trace suitable for photo-graphic recording); and long-persistencegreen (for the study of transient phenome-na, the trace of which must be held on thescreen for an appreciable period). There isalso the black-and-white screen suitable fortelevision work, including the latest "mem-ory" screen for the minimizing of flicker atslow repetitive picture rates, as dealt withfarther on.Du Mont cathode-ray tubes are divided

into two bwad groups, namely, Oscillo-tTOns for oscillographic application, and'Teletrons for television work.

\Vitf, tlle advent of commercialtelevision. tllese 14-inch Duf.1on! teletrons became a pro-duction item ratller than a labo-ratory masterpiece. Dozens 01tIle 14-incf, and 20-incf, t<,le-trans are produced eacf, work-ing day in equipping as rnanyDu f.1ont television receivers.

~---_.

The intensifier feature-tT-Ie first radi-cal improvement made in cat/lOde-raytubes since tlte broad basic principleswere laid dOflln several decades ana~fllas scareel by Du Mont. Note theintensifier rings near tTIC flared endof tube.

Topping the many Du Mont cathode-raytube developments is the intensifier electrodefeature, covered by basic patents and firstintroduced late in December 1938. Thisadditional electrode in the form of ametallic-deposit band on the Inside wall ofthe tube, close to the screen end, greatly in-creases the brilliance without correspond-ing loss in deflection sensitivity. This elec-trode accelerates the electronic beam afterdeflection. From the practical standpoint,this feature brightens the pattern equiva-lent to doubling of the accelerarting voltage,yet not causing so great a decrease in sensi-tivity as actual doubling of this voltagewould produce. Or to put it another way,instead of a reduction in pattern size of50%, as doubling the accelerating voltagewould normally produce, the voltage withuse of an intensifier electrode reduces thepattern size by only 18%. Thus the designof deflection amplifiers has been consider-ably simplified. The vivid screen traces ofDu Mont oscillographs and television setsare due to the Du Mont intensifier feature.It is felt that this new improvement incathode-ray tube design-the first funda-mental improvement affecting sensitivity

since the inception of these tubes over 40years ago-is proving invaluable in multi-tudinous applications.Du Mont tube developments have also

included the phasmajector, which providesa uniform television test signal, as well asa simple, inexpensive demonstration of tele-vision principles. Likewise the 14-inch and20-inch teletrons, for television reception.Meanwhile, the Du Mont organization,

as a by-product of its cathode-ray develop-ment work, did evolve the cathode-raytube null indicator, popularly known asthe "magic eye", used not only for the pre-cise tuning of many modern super-hetero-dyne receivers, but also in numerous radioand industri'al instruments. The radio ap-plication rights to this invention were soldto ReA, while Du Mont retained all non-radio application rights.Today Du Mont cathode-ray tubes are

available in many types and sizes andscreens, ranging from the small 3-inch os-cillotron for low-priced oscillographs, to thelarge 9-inch oscillotron, and again to the14-inch and 20-inch teletrons. The organi-

Allotlwr Dil Mout development. tile PI",.sma;ector, 1"'5macle possihle tlw silllple dem.onstraLion of television. prin-ciples. Also, it provides a urtifonu, unvarying, alwaysaflailnble test pattern or irnage for cllecking televisionequiprnent.

zation also produces a selection of half-wavehigh'vacuum rectifier tubes and gaseousdischarge tubes for use in sweep circuitsand their power supplies.

THE CATHODE,RAY OSCILLOGRAPHGOES COMMERCIAL

Having provided the very foundation forcathode' ray oscillography, with its practical,uniform, low'cost tubes, the Du Mont or'ganization was soon called upon to furnishcomplete oscillographs as well. And so thefirst Du Mont oscillograph, Type 127, wasannounced late in 1932, with the statement"The completeness and moderate price ofthe unit bring the art of cathode'ray oscil'lography within reach of present,day labora'tory budgets". The instrument was classi'fied as "portable". It consisted of twounits, namely, the case containing powersupply, sweep circuits and necessary con-trols, and the 3'inch cathode'ray tube ina separate adjustable holder. The price was$185.00.Also in 1933, the Du Mont organization

introduced the Macneil amplifier, with acurrent sensitivity of 4/10,000,OOOth am'pere, for the operation of string torsiongalvanometers. But the rapid strides madewith the cathode'ray oscillograph sooncaused all efforts to be concentrated onthis technique, so further attempts to super'sensitize string galvanometers were aban'doned.

How Du Mont engiueers sooncommercialized tlte catllOde-ray oscillograpll is grapllicallytold here. At left. tlte originalDu Mont oscillograpl" ,!'itl,separate Illbe holder. AI riql,tthe portable instrument ideaof 1938. establislling file gen-eral design of today.

Always appreClat1l1g the difference instandards between precision laboratory workand general or industrial usage, the DuMont organization as far back as July1933, introduced its first laboratory'gradecathode'ray oscillograph. This was a rack,type instrument with a 5,inch tube, butalso available in 9,inch. It had a linear,sweep range of 10 to 5000 cycles, and washailed at the time as a marked advance inprecision equipment. The first truly port'able single'unit Du Mont oscillograph types,Type 137 with 5,inch tube and the 138with 3'inch tube, were announced in Janu'ary 1934. These instruments were primarilyintended for broadcast modulation studies,and sold for $165.00 and $85.00, respec'tively. By fall of that year, came the Type142 5,inch oscillograph which, with its fourcontrols on the panel, bore just a faint sug'gestion of present,day Du Mont general,purpose types. By January of 1935, the3,inch instrument sold for $99.50 and theHnch for $116.50, these models havingcontrols for frequency adjustments, syn'chronization and sweep amplitude.

February 1935, saw the introduction ofthe Electronic Switch, described later.

A further drop in prices occurred byfall of 1935, when Type 148 3,inch oscil,lograph was offered at $94.50, with a 5,

----~----

inch job at $106.50. These instrumentswith their nine knobs on the front panel,were getting fairly close to present-daymodels. A basically new sweep circuitjust incorporated made possible a 10 to30,000-cycle range, improved linearity andexceptionally fast return trace. Also, theseinstruments included an improved synchro-ni4ing circuit permitting the locking of thesweep with fractions as well as multiples ofthe wave. The cascade amplifier provideda I-inch deflection with 0.2 volt signal.A single knob controlled all the switching.As a final touch of refinement, these in-struments werc provided with the patentedcalibration screen scale so characteristic ofDu Mont oscillographs. With the adoptionof the bright stainless panel featured byNovember 1935, the present general styleof Du Mont instruments was inaugurated.Prices still declined, in keeping with

better and greater production facilities, asthe Type 154 3-inch oscillograph was an-nounced at $74.50, early in 1936.Coming to the present time, there is the

current 3-inch general-purpose refined os-cillograph, Type 164E (only $64.50) whichleads the field in the moderate-price range,as well as the 5-inch Type 168 ($116.50).Both types have been and continue to beproduced in large numbers to meet thelively demand. These popular instrumentshave made Du Mont a household wordthroughout the world in universities andtechnical schools, laboratories and engineer-ing departments, repair shops and servic-ing organizations, and other institutions.To meet the more exacting requirements,

Du Mont engineers have developed othermodels such as the Type 171 with severalrefinements over the 168, and the 175 pro-viding exceptionally convenient operationand flexibility in one complete instrument.But the peak in oscillograph design to datehas been attained in the Type 208, whichprovides an amazing array of features foundin no other single standard oscillograph nowon the market. Such features as the use ofthe intensifier tube for brighter screen

Exampes of ftOW

tllO co 1110d e-ra yoscil{ogropl, writesils own slory ...

TllO effect of l1ighinductance in agiven circuit, sllow-ing how tllOdampedoscillation I a k e splace 01 1110 slar!of eacl, 1",lf cycleof tIle square wcwe.

TflO response of agiven amplifier to a261,ilocycle square-wave signal.

A call1Ode-ray stop-watch effecl. show-ing how Ihe opera-Han of a fwD-waysnapswilch is ac-curotely Hlned inmilliseconds.

Oscillogram ofsl.inwli showingconstancy of formand amplitude ob-tained with the DuMont Varia.ble -Frequency Stimu-lator.

Analf,er oscilfo-grOIn of stimuli oh-lained with 1110same means. Thetime intervals inbotl, inslances: 1miTTisecond.

images; constant-impedance continuously-variable input attenuator with .zero fre-quency discrimination; four easily-accessibledeflection-plate terminals; symmetrical de-flection of both axes for fine focus and nodistortion; a beam switch which instantlyextinguishes the spot; undistorted four-cyclesquare-wave response; flat response to 100,-000 sinusoidal cycles per second; sweep fre-quencies from 2 to 50,000 cycles per second;nearly 15-inch time-base with 2yz times full-scale deflection; regulated power suppliesfor no pattern shift; a functional panel lay-out; complete portability, extreme rugged-l1ess, full dependability-these featuresindeed, in a standard, moderate-pricedoscillograph appropriately reflect a decadeof untiring specialization.In addition to the foregoing and other

standard types, the Du Mont organizationhas built and is constantly called upon tobuild special oscillographs to meet out-of-the-ordinary requirements. Some of thesespecial jobs attain most elaborate propor-tions, particularly the instruments built forpresent National Defense requirements, forthe leading laboratories, for almost everybranch of industry, and for other criticalusers.

Oil :"1011f Electro"ic Swilch (I,'ft) "sedin conjunction with DLl MUllt Oscillo·grapll. T/lis ingenious instrwllelll servesto place ffCO or more independent signolson. tile 5creen of n silln1c cot/lOde-myoscillogroph. 7\'ole fypicnl ex",,,ples. Tlwindepenrlent s(qn(l[ tr(lces COil be dis-lAnced for il1rlivit!",,1. de/nileel st"ely• orsuperilflpos(>J on SUHle hose lille for directCOfllporisons.

THE ELECTRONIC SWITCH

Realizing the occasional but vital needfor placing two voltage or current phe-nomena on a single cathode-ray screen forsimultaneous or comparative studies, DuMont engineers developed the ElectronicSwi tch, first announced in February 1935,as Type 143. This was a laboratory job,as distinguished from the present Type 185in its trim, convenient, fully portable casewith carrying handle, generally matchingoscillographs with which it is used.The exclusive Du Mont Electronic Switch

has done more to increase the versatilityand value of the cathode-ray oscillographthan has any other single development. Thisrelatively inexpensive accessory makes pos-sible the inspection and comparison of waveform and phase of two voltages or currentsfrom different parts of the same circuit, ormatching of wave form of a standard waveand any other wave. For example, it ispossible to see the input and output waveforms and phase displacement of an ampli-fier. Thus in the high-fidelity amplifier theinput and output waves cover one another,while even a slight distortion of phase shiftwill noticeably displace the two oscillograms.Another useful application is to apply atiming wave in conjunction with the waveunder observation; for example, in testingswitches or relays it is possible to inspect

----~~

the length of time it takes to complete theswitching if switched potential and timingwave originating from an AC source ofknown frequency, are present on the oscil-lograph screen.Essentially, the Electronic Svvitch is, as

its name implies, an electronic means, de-void of mechanically moving or vibratingparts. It comprises a switching tube andtwo amplifiers, or one for each phenome-non applied. The switching tube operatesto cut in one amplifier, then the other, atsuch rate that the two phenomena appearon the screen at the same time. In additionto switching, this instrument also amplifies.The original Type 143 whose design anddimensions pretty much confined it tolaboratory usage, has since been super-seded by the fully portable and lowerpriced Type 185.

THE CATHAUTOGRAPH ORELECTRONIC PENCIL

Among the many ingenious adaptationsof the cathode-ray technique made by Du

Mont engineers. the Catl1autograph orelectronic pencil attracted wide attentionwhen it appeared on the cover of theJanuary 1933 issue of Electronics. This de-velopment has far-reaching possibilities.Briefly, the Cathautograph is a means offlashing simultaneously the written wordor sketch over wires or radio. A pencil,connected by levers, works across two re-sistors to control two sets of plates of acathode-ray tube. The tube is providedwith a "memory" type screen, or one witha very slow decay rate, so that the traceremains luminous for :;0 seconds or so fol-lowing the activation of its fluorescentsalts. At the transmitting end the altera-tion of the two resistance values, followingthe writing pencil, correspondingly shiftsthe cathode-ray beam across the receiverscreen. As many as ten words can beseen on the screen. As the eleventh wordis being written, the first word is fadingout. In 1933 Mr. Du Mont greeted hismany friends with New Year's cards writ-

In addition to simultaneousobservaLi,ons and studies ofscreen patterns, tIle catllOde-ray oscillowaph may he sim-ply employed For makingpennanenL records with or-dinary cOl1uuercial photo-grap/tic eqfli.p,nenl. Here is

a typical setup in tile CruFtLaboratory, Harvard Uni-versity. using a [cicCI camera.

i\ precise means of cletertnining whelTler a singeror inslrutnenl is "flat" or "s/lorp", or exactlyon pilch, is provided by tlw Du Mont Reso,lO-scope. 'The electrodynotnic tnicropllOne servesalso as a loudspeal<er, and sounds tlw pilch ofanyone of the notes of a Full chromatic scale.hv means of the selF-contained tuning Forks.

ten by the Cathautograph. It was a star-tling innovation. The military as well asintercommunication possibilities of this de-velopment can hardly be exaggerated.

THE RESONOSCOPE SOUNDS THE

PRECISE MUSICAL PITCHEqually ingenious was the Resonoscope,

introduced early in 1937. This instrument,consisting of a special cathode-ray oscillo-graph and a standard set of tuning forkscovering the musical frequencies of thetwelve notes of the chromatic musical scale,provides a precise means of checking themusical pitch of musical instruments andvocalists alike. The frequencies producedby the twelve electrically-driven tuningforks are used to synchronize an oscillatorin step with them. The oscilbtor in turnprovides the horizontal sweep circuit for thecathode-ray tube. The output of a dynamicmicrophone used to pick up the sound underinvestigation, is fed to the input of a vol-tage amplifier. The output of this ampli,fier is placed on the vertical deflectionplates of the cathode-ray tube. This pro-vides a visual indication of the wave formof the musical note under investigation,

If the musical note under observation is ofthe same pitch (or frequency) as the pre-determined standard being used, or anyharmonic of it, the wave form will appearto stand still on the screen. If the note isflat, or lower in pitch, then the horizontalsweep 5tandard of the wave form will ap-pear to be moving to the left. If the noteis higher in pitch, or sharp, so to speak, thewave form will move to the opposite di,rection, going toward the right. This in-dicates to musician or vocalist whether heis in tune, is sharp, or flat.In musical circles the Resonoscope has

met with exceptionally favorable recep-tion. Many such instruments have beenbought, particularly by musical instrumentmakers, as a simple, positive, rapid meansof checking and adjusting for pitch. Inaddition to just the matter of pitch, theResonoscope also permits the intricate waveform of any musical instrument or voice tobe studied graphically, thereby permittingvisual comparisons between different tonequalities, and appraising the overtones andharmonics that go to make either a mail-order violin or a Stradivarius.And so from its very inception, the Du

Mont organization has constantly soughtnew applications and ingenious adaptationsof the cathode-ray technique. At this verymoment, its engineers may be at work ona quantitative and qualitative means forstudying automobile body noises; a checkupof airplane vibrations and stresses; an anal-ysis of the burning rate and explosive forceof given smokeless powders; the geophysicalexploration of oil-bearing strata; the char-acteristics of a Diesel engine in actualoperation; and so on and on. It is inthese applications and adaptations, fully asmuch as in the development of the cathode'ray equipment proper, that the Du Montname has identified itself so intimately withthis fast-moving art.MEANWHILE, TELEVISION COMES

ALONGOf course the outstanding adaptation

and indeed the very climax of the cathode'

-----~------

Because of its extreme versatility andready rueanS of grapllically irulicat-i1lg circllit and operative conditions,the Du Mont oscillograph soan be-Cattle 0 "must" instrulnent witll capa-(lIe raelio serpiccmen for use either in.ti,e sllOp or out all tile job. Its useIHIS weatl)' expedited and simplifiedserpicillg loelay's cOlnplicafed radioreceipers.

ray art is television, for here the require-ments are far more critical than those ofindustrial and scientific usages. Since pres-ent-day electronic television, as distinguishedfrom the very limited possibilities of thewhirling disc or mechanical technique ofthe past, is simply refined cathode-rayoscillography, it was a foregone conclusionthat the Du Mont organi"ation would enterthe television field when, where and as thisstruggling art offered proper inducements.Du Mont the man personally kept a

weather eye on television developmentsboth here and abroad during the early'thirties. By the summer of 1937 he de-cided to check at first hand the British,German, French and Dutch television ac-tivities. A flying trip to Europe and backhome again, provided the very essence of

commercially-feasible 'television. He broughtback data, ideas, tubes, receivers, plans.From the beginning of its television ac-

tivities the Du Mont organi"ation laid downand has adhered to several broad funda-mentals which it believes inherent to suc-cessful commerciali"ed television. First, DuMont televisors are characterized by largescreen size. Despite pressure for lowerprices, Du Mont has insisted on the 14-inchdiameter teletron as the minimum size forsatisfactory viewing. Again this organi"a-tion has steadfastly adhered to the use ofthe electrostatic type tube, because ofmarked advantages over magnetic-deflectiontubes particularly 111 maintaining cleanscreens free of "burns" or dar~ spots. Stillagain, Du Mont set design has favoreddirect viewing, without mirror or otherintermediates. Finally, Du Mont engl'neers have firmly believed in a flexibletelevision system, whereby scanning patternand picture frequency rate, while adjustableto meet changing needs and program subjectmatter, might be confined to the transmit-ting end, with receivers automatically fall-ing in step, thereby minimi"ing the trouble-some obsolescence factor.It was e;lrly in 1939, or just on the eve

of the inauguration of scheduled television

Ti,e nil Tont oscillograph is to be fOllnd in engi-II('(',-inn and rpsearcfl loborcttori.es cpcrywllCre, forif inclicotps precisely w/lat is goi1l0 on in elcctricolcirCllits.

~----_.

It all sfarted tl,is way ... Allen 13. DIL Mont (riqht) oncl his associate. Dr. Goldsmitl,. hack in theclays of the string of stares in Upper l''lonfdair, working all. early cathode-ray television. TIle pllOsma-jector or image-transmitting tuhe was developed as (t m.eans of prop;ding a standard signal. TIlLsimage of Lincoln was viewed hy tl,e engineers for hours on encl, clay after clay, until tlwy knewevery line hy Twart!

programs in the metropolitan New Yorkarea coincidental with the opening of theNew York World's fair, that Du Monttelevision sets began rolling off the assemblyline. Hundreds of sets produced ahead ofany others, were eagerly snapped up byradio merchandisers anxious to be the firstin their locality to show a real televisionreceiver. As a drawing card nothing everexcelled these first sets. Traffic jams infront of show windows featuring such sets,had to be broken up by police. Stores werecrowded from morning till night, and yetregular television programs were still tocome! Set screens remained blank.However, with the Spring came tele-

vision programs. Hundreds of Du Montrcceivers went into action. In homes, tav-erns and hotels, clubs, theatre lobbies, andother public places, countless folks saw realtelevision for the first time. Du Mont offi-cials anxiously watched these audiences.Was it just passing curiosity? Was tele-vision a new side show? Could televisionprograms hold the public interest? Theanswer was a decidedly big YES. Tele-

vision has a continuing, lasting, supportinginterest. It is more than a mere experi-ment or demonstration. It can be and willbe a real business.

COMFORTABLE TELEVISION ByDu MONT

Du Mont has a distinct aversion to"peep-hole" entertainment. Perhaps in thevery dim past he may have viewed baseballgames through a fence knothole! Or morerecently he had resented the postage-stampimages of the Jenkins televisors, which hehimself squinted at hour after hour untildriven to work out the larger images of-fered by the refined DeForest televisionsystem, under his supervision. At anyrate, his instructions to co-workers are.simply: large, larger and still larger tele-vision images, for the utmost comfort oftelevision audiences.Beginning with the 14-inch telctrons,

providing 8 x 10 images that can be com-fortably viewed by a doz,en persons, DuMont engineers have more recently gone tothe de luxe model televisor utiliz.ing a 20-inch teletron with a full 11 x 16 screen._________~----------.II

For tfIC simple, inexpensive demon-stration of television scanning prin-ciples, tf,e pllUslllojecLor tuhe wasintrodflcecl in conjunction with "vastandard nil MOllt oscillograpl.s.One, witl, pl,osntajeclor tuLe in-serted in place of usual cathode-raytube, serpecl as transmitter. Theotl,er reproduced ,flC image on itsscreen:

Meanwhile, developments have been underway on projector-type teletrons for pro-jecting images through optical systems andon to large screens for theatre-sized audi-ences. The Du Mont trend is towardslarger screen images. There is no interesthere in smaller images, regardless of anyprice considerations. Yet the prices of DuMont televisors have been consistently re-duced, and may be further reduced on thebasis of greater production volume withcorresponding economies, rather than vir-tual cheating on television performance.Du Mont television receivers are made

in various models. The table model hasproved by far the most popular, becauseof moderate price. Provided with a short-wave sound receiver in .addition to the14-inch teletron video receiver, this table

Ancl t{wn carne tIll! (irst cfHlIlII(,fciol telelJision

rec{'il'"r in tile l'.' S.-tl", n" lYI"nt tablemodpl, pror'iJinq complete sigl,t-ond-soundfPCl!ption!

model supplies complete sight-and-soundentertainment. Console models are alsooffered, topped by the de luxe console with20-inch teletron for large-screen images,television sound, and a high-fidelity all-wave broadcast receiver.

THE NEED FOR TELEVISION

FLEXIBILITYReceiver obsolescence remains bugbear

No. 1 of television workers. Heretoforewith every change in transmitting stand-ards, receivers out in the field have hadto be serviced if not revamped to accom-modate altered signals. Obviously no manu-facturer could be expected to go aheadwith thousands of television sets based ontoday's transmitting standards, when to-morrow's might render those sets obsoleteor at least subject to costly alterations.Meanwhile, no video broadcasters wouldbrave the storm of protests, let alone im-mediate loss of the major portion of hislookers-in, by attempting to change trans-mitting standards. And yet the televisionart at this early date could hardly befrozen at current standards, for that wouldobviously limit its entertainment poteD'tialities. What to do?The Du Mont organization in 1939,

despite the inauguration of scheduled videobroadcasting of fine entertainment valueparticularly in the metropolitan New Yorkarea, began work on a flexible televisionsystem, whereby video broadcasters wouldbe free to alter transmitting standards inkeeping with program and audience re-quirements, with television receivers auto-

• Tele,'ision transmilter \V2XWV (lnd ilsstudio focilities. ready to "go on t/te air":(I) Lolly tower (lnd onlenno ot 515 Modi-son Avenue dominates tlte midlown skylinefrom (I I"'igll! of 650 feet uhove tile side-wolks. (2) Steel tower supports tile (In-

tenna must 165 feet ahove tile .J2-storyskyscrnper. (3) A halter)' of lotest modelDu Mont telelJision cameras cover studioanel oulside programs. ('I) Careful moni-toring of pickUps insures uniform televisioninlUges of fine pictoriul quulit)'. (5) Banks

Uu Mont New YTelevision

-orkStation W2XWV

of fluorescent lamps provide cool, comfod-able. non-do=:ling illuminotion for tile per-formers_ (6) Studios are located on the14t/l floor, w/life transmitting station is onthe 42",/ floor of this conveniently situotedmidtown skyscraper_ (7) Tile electronic

lIi<.'w-fillder pnohles Dn ;"10nt cameranlen

/Jrf'cisely to check up their images in strictlytelevision terms_ (8) The powerful videaand audio transmitting equipment providesstrong signols tltrouglwut the metropolitanurea.

matically falling in step. This in markedcontrast to the inflexible 'system sponsoredby the Radio Manufacturers Association,in which free-running sweep circuits atthe receiver are available only for certainscanning and image-repet}tive-rate stand-ards. In the Du Mont Synchromatic Sys-tem the transmitted signal actually drivesthe sweep circuits of the receiver, whichmust follow any scanning, interlacing orimage-repetitive rate standards being trans-mitted. In other words, there is just thatrelative difference between R.M.A. andDu Mont systems as exists between a carwith flanged wheels pushed along a track,and a bus that can be steered over anyroad according to orders.With the Du Mont Synchromatic Sys-

Du Mont consoletelevision receiv-er. available at apopular price. Ade luxe model in-cludes an all-wave receiver inaddition to televi-sion pictures andt.elevision sound.

Rpo":, two complete ,,('ceivers in one-,11e television receil'er and tIle telc4vision-sound receiuer-tlte DH Montchassis is tlwrou9111)· clleckecl b\" capa-ble engineers before b~i"g placed inits cabinet and "",de nl'ni{nble forshipment. TIle components arenlounted for ready te~"irlg and serl'-icing.

tern all controls for the synchroniz;ation ofsweep circuits are eliminated at the receiver.Such controls are usually provided for afine frequency adjustment of the sweep

An early television image. Remarknbly brigl,tnncl detniled images ore obtainable with todny'stelevision receivers--pictures fully cOHlpomblewith those of home movies.

oscillators. Unless synchroniz;ing action is,therefore, very positive, these controls arefrequently in need of adjustment. Further,should a change in scanning standards beindicated in the light of future develop-ment, these self-oscillating sweep circuitswill not provide the desired flexibilitysince they would require re-synchroniz;ationadjustment. The use of the Du Mont auto-matic type sweep circuit at the receivereliminates this limitation of the R.M.A. tele-vision system, and in its place provides asystem which will cause the television receiv-er to follow any scanning changes in the~elevision transmitter without loss of syn-

~--------------

chronization at the receiver and withoutthe knowledge of the user except by anevident increase (or decrease, if desired)in picture detail.Du Mont automatic synchronization of

the television receiver is effected by utiliz-ing a sweep circuit which is not of the self-oscillating type. In its place is substituteda discharge circuit which is always readyto operate \.vhenever a synchronizing pulseis applied. Upon application of such syn-chronizing pulse, this circuit gives one, andonly one, single, linear, horiz;ontal sweepof the luminous spot across the fluorescentscreen. It is obvious that, with a circuit ofthis type, the number of horizontal scan-ning lines per frame, and the number offrames per second, are both under com-plete control of the transmitter. Picturedetail may, therefore, be increased fromtime to time as the state of the art permits,and this may be done at no sacrifice in re-ceiver operation, no obsolescence of exist-ing equipment, and without restriction atthe transmitting end.

THE "MEMORY" SCREEN AND ITsVAST IMPLICATIONS

In 1940 Du Mont engineers developedanother startling television innovation -the "memory" screen. This is a fluorescentscreen that has a relatively slow decayrate, so that one image is held over until

the next appears. In the usual teletron,images appear and disappear almost in aflash, with the result that there is a notice-able flicker due to the intervening darkinterval if the repetitive rate is cut con-siderably below the R.M.A. 30 frames persecond standard.Now if there were all the room on the

air that could be wished for, televisiontransmission would be a simple matter.Taking all the elbow room needed, therewould be no need and indeed no thoughtof conserving on the band width. How-ever, with 44 Hines and 30-frames-per-second, the heretofore R.M.A. standardsnecessitated a transmission band width of4.5 megacycles for the video signal alone.A total band width of 6 megacycles accom-modates the sound component and permitsof adequate separation between adjacenttelevision channels. Each television channelrepresents as much ether space as would600 sound broadcasting stations. It is im-mediately apparent, then, that if this bandwidth could be materially reduced, moretelevision stations might eventually operateto serve the public.Cutting down on the number of scan-

ning lines is of course a direct attack onthe pictorial definition, and is generallytaboo. Cutting down on the image repeti-tive rate can also reduce the band width,but it also introduces marked flicker when

Just a corner of the Du Monttelevision receiver production linewhich has turned out many suchsels already. Despite the intrica-cies of tlle television receiver, itis simply a modified oscillograph.and is 110ndled as such in the DuMont plant long speciali=ing inoscillowaphs.

-----~.~~----

the usual fluorescent screen is used. There-fore, Du Mont engineers recently cowdueted exhaustive experiments on manykinds of fluorescent screen materials, aimedat a controlled decay rate to provide the"memory" or carry-over effect from oneimage to the next, bridging over the darkinterval that causes flicker.The earlier Du Mont "memory" type

teletrons produced rather vivid orange-and-black images, which were somewhat objec-tionable. Further developments and refine-ments gradually corrected the color untilpresent "memory" type teletrons provideblack-and-white images. With the "memory"screen, the repetitive rate is slashed in half-15 frames instead of the former 30.Yet there is no apparent flicker, even whenreproducing pictures with considerable andfast animation.Meanwhile, the halving of the repetitive

rate permits transmitting pictures of agiven number of lines, with a 50% reduc-tion in band width. Thus we can get

along nicely within a 2.0 megacycle bandinstead of the previous 4. Or cutting thescanning standards, 325-line picture may betransmitted on a 1.0 megacycle band.Either of these transmissions would proveuseful in providing a natio11'wide or world-wide television service on a carrier fre-quency between 20 and 30 megacycles.With such wider coverage, many of thehitherto economic problems of televisionmay possibly vanish.Or if the present band width is to be

retained, the Du Mont "memory" screenpermits using the extra elbow room gainedby halving the repetitive rate for an ill'creased number of scanning lines, andtherefore greater pictorial definition. InDu Mont demonstrations 625 lines and 15frames (30 fields) has been chosen asan excellent compromise.With the Du Mont flexible Synchromatic

System, together with the "memory" screenfeature, it becomes possible to offer high-definition programs for the compact metro-

Hpcoglli=inn tIle widera.nge of !(-"('uision pro-gran!. circllt1l.slallces, t.l,eDIt MOllt orgoll;=olio(l.decid"d on t.lIC unit pionof Clss(>lnl-)[ing requir('J"elwins'.lnatl,en"ards.a dloice of stnnclonl,porta.hle, sel{-conf.aineclunits is alJailable. Tlleseare cotlllecled togetlwrto form. a ..cl,ain" tomeet ,IHY program nepcls,erITH?,. for outside piCkUpor for studio IIse. Thisis SOfne of ,lie earlierequipment. prior to tIleelectronic view finderfeature.

DIL [\/Ol1t r~por,~J iTie19-10 Pr~si<I~I1'iol Flec-lion ,-('turns pia televi-sion. Tile camera pickecllip tIle election returnsflnsTleel on (J tmllsluscentscrf'f'n. in f,.onL of it,wI1if(~ die opC'/'(ltor llIolli-tor~rl '{,e "ideo sigl1o{s,in tl'e DIL j'1ollt ,\'elUYorl, stot.ion, \V2X\VV.

politan areas, using the standard 6 mega-cycle band widths, or, on the other hand,medium-definition programs to the outly-ing areas that may best be reached ifsome elbow room can be squeezed outamong the higher wave lengths that havegreater range. Naturally, reduced bandwidth is imperative if higher wave lengthsare even to be considered,At a time when the television art seemed

ready to be "frozen" for several years onthe basis of the R.M.A. standards of 441-line 30 frames, the Du Mont demonstra-tions of a flexible system attracted the at-tention and sympathetic consideration ofthe Federal Communications Commission.During 1940 and the first half of 1941,many demonstrations were staged for theCommission and for all television interests,including direct comparative tests betweenR.M.A. and Du Mont signals, On the rec-ommendation of the F.C.C., the NationalTelevision Standards Committee was formedfor the purpose of studying various tele-vision systems and formulating a set ofstandards to be submitted to the F.C.C.This activity has kept the television art in

a state of flux, and while this may havebeen deemed unfortunate from the stand-point of earlier commercialization, it hasserved to encourage more refined televisiontechnique which in turn will prove morethan worth while as television becomes areal business. Du Mont, regardless ofwhat standards may be finally adopted,feels that its unselfish, progressive, yes,argumentive attitude if you will, has beenfor the best interests of all concerned.

Du MONT AT THE TRANSMITTINGEND

Cognizant of the fact that television re-ceivers are simply useless in the absenceof video programs, and harkening to thedemands of various interests throughoutthe country for television transmitters, theDu Mont organization has been producingtransmitting as well as receiving equipment.From the iconoscope camera to the video

transmitter, including the necessary audio,Du Mont is equipping television broad-casters. Several Du Mont-equipped sta-tions have already been set up 111 vanousparts of the country, with more equipment

--------------------~---------------_.

Yes, television did take 1/Old-a",1 'I'itl, a bCll1fj!

Particalarly in caIes ",,,I iI/II> 0",1 d"bs. Here'sa typical caIe in the heart of Ne,,' Yor', City, !I'itl,television entertainrnent 011 top.

on order. Such Du Mont equipment IS

designed for either the Du Mont Synchro-matic System or any other system that maybe desired, but the former is naturally rec-ommended because of its flexibility andgreater possibilities now and in the future,as already discussed.

In designing television studio and trans-mitting equipment, Du Mont engineer"shave sought to reduce the proposition toits simplest elements. Instead of the usuallarge assemblies confined either to studiouse or to outside pickup work, Du Montequipment comprises a "chain" or collectionof separate, compact, portable, interconnect-ing units that go to make up any requiredstudio or mobile facilities. In other words,the "chain" is made up of selected stand-ard units. Each unit is complete by itself,in an attractive metal case, with leathercarrying handles and removable protectivecover. In the studio, the units, such as thecamera control, camera control power sup-ply, shading control, line amplifier, lineamplifier power supply, synchroniz,ing-signal generator, and the power supplyand scanning unit for the synchro-nizing-signal generator, are simply placedon a table or metal shelving, and operatedwith the iconoscope camera. The self-same units and camera can he packed into

'Tfle lefeuision rpcciuer 1105 come to he part of ,lIeatmospllere of tile top room. TI,is ol/e happens 10

TlOve a sound-recording ouffit as well. to entertainits patrons.

a passenger car and taken outside for re-mote pickup work, operating either overa special coaxial line or an ultra-high-fre-quency radio relay transmitter, the lattercalling for corresponding equipment. Thisdual usage of the same units is of signifi-cant importance to the smaller televisionstations in that the investment and mainte-nance are kept at a minimum.Du Mont "chains" are also made up for

film pickup work. The movie projectorimages are picked up by the iconoscopecamera. One camera, suitably mounted ona wheeled platform which in turn permitsshifting the camera from one projectorto another, can handle two or more pro-jectors of either the 35 millimeter theatretype or the 16 millimeter amateur type,the latter promising to be most popularin much local television program work.

ELECTRONIC VIEW,FINDER

As in its extensive cathode-ray pioneer'ing, so in its television developments, theDu Mont organiz,ation has had its ownideas. Of outstanding importance, forexample, has been the introduction of theDu Mont electronic view,finder for theteleviscn camera, whereby the operatoractually sees the images as picked up intelevision terms, just as the audience seesthem, rather than in the usual optical terms

-----~-----

Even oul in llle sticks, as tlleY say, television 110sproved Cl big drawing card for taverns, especiolfyon those f1ig11ts wIlen tllere are sporting ('vellts.

which mean little more than aiming thecamera. The electronic view-finder is ac-tually a miniature televisor attached tothe camera. With it, the cameraman mustknow precisely what he is picking up notonly as to exact field of view, but also hislights and shadows, action and other details,translated into television terms which, afterall, are what he is primarily interested in.Lenses can be changed, while the electronicview-finder automatically checks the lens.This development is held to be the mostoutstanding step ahead since the iconoscopecamera was first introduced several yearsago.Other innovations, improvements and re-

finements too numerous to mention, char-acterize Du Mont studio and transmittingequipment, and reflect a decade of speciali-zation in the cathode-ray art which remainsthe very foundation of present-day tele-vision.

Du MONT VIDEO PROGRAMS IN THE

MAKING

Meanwhile, the Du Mont organizationhas been on the air with experimental sig-nals and with test video programs. Forthree years past it has been operating anexperimental television t ran s m i t t e r ,W2XVT at the Passaic plant. This trans-mitter has served as the testing ground for

Television fws clone 0 reol soles-promotion job forIllHulreds of eolillO places II,,-ou9'lOut tile metropoli-tan New Yor" area. Toclay it is a "must".

much of the Du Mont television engineeringwork on transmitting and receiving equip-ment, and also has served for some of thedemonstrations for the F.e.e. and televi-sion interests generally.During the past year a video broadcast-

ing station has been under constructionin the New York studios of the Du Montorganization at 515 Madison Avenue. Aprogram staff has been gathering and or-ganizing program material in anticipationof commercialized video broadcasting. Thisstation, W2XWV, is located on the topfloor of the 42-story skyscraper. The trans-mitting aerial is supported atop a polewhich in turn rests on a lofty steel derrick-type tower, fully 650 feet above sea level,commanding a sweeping view of the entiremetropolitan area. Recently the transmit-ting equipment has been completed, withthe installation of the 4000-watt peak-ratingvideo transmitter, and the 1000-watt (2000-watt F.M.) audio transmitter, for completesight-and-sound broadcasting.The studio facilities provide for direct

pickup as well as film programs. Du Montengineers have installed a fluorescent light-ing system in the studio, so that performersare no longer subject to intense glare anduncomfortable heat experienced with usualincandescent illumination. The fluorescent

-------------~I111.--~J~~~..----------

Not only receivers. hut complefe studio and transmitting facilities as well llOve heen provided hyDu l\10nt in promoting general television programs. Here is a typiCClI insfance~fhe D" l\10nt lelevisionequipment, including tile earlier model of electranic view finder on the camera, used ii, tl,e Balahan& Katz television sludios in CI,iCClgo.

lighting closely approximates daylight andis well diffused for ideal television images.Baby spots are used for modeling and dram-atiz.ing when required.In conjunction with the New York tele-

vision station, there is a mobile transmittermounted on a truck and provided with com-plete pickup facilities. The ultra-short-waverelay signals from this mobile transmitterare picked up at the main station by receiv-ers, duly amplified and monitored, andpassed on to the main transmitters for re-

Again Du Montscored in radicalilnprovenl€n.Ls--thistime with tIle elec-tronic view-find~r.lUll ielt provides thetelevision ca,neru-111.on with a realcheckup of hispickup. (Casing re-,noved to sT101V

cletoils.

broadcasting. It is anticipated that muchof the earlier program material will beoutside pickups.A battery of 35- and 16-millimeter

movie projectors are housed in a fireproofroom. Movie images are projected throughfireproof windows and on to the iconoscopecamera which, mounted on a wheeled truck,can be brought in front of any desired pro-jector. It is anticipated that many earlierprograms will feature movies, particu-larly special films prepared exclusively fortelevision requirements, which may be madeavailable through the Paramount Picturesaffiliation enjoyed by the Du Mont or·ganiz.ation. Sound films will be used, aswell as silent. Turntables are available forelectrical transcriptions.All in all, Du Mont is ready to place

suitable video programs on the air. Withthe advent of commercial television licenses;with a completely equipped, thoroughlyengineered, ready-to-operate station in the--_-:~---~I

Onl)' h)' such a large illuslration can DuMan I/IIorlunansllip anJ Jesign he fnll)' oppredared.Here is a DuMont Jual film pickup cI,ain. pro-viding for the sinlultaneous pickup of two ,. rlwlJip"

progrluns. Tile operators uiew tile images on tileI"rge monilor screen, anJ cI.eck lecl,nical delailson rI,e smal/er C<llllOde-ro)' screens he/ow. S"d,equipment I,os alrendy been supplied to spveralIplt)caslers.

@ ,c...,,,,~,

A Du Mont dual canlera clloin, cOlnprising two CQrneras equipped with electronicv;ew~finders. and tlte necessary associated equipntent in IlOndy portable unitform, for use either in studio or outside. The dual use of such equipment isparticularly significant to ,I,e smaller local telecaslers soon to dot this cOllnfry.

very heart of the leading metropolitanarea; with a program director and staffwhom, during the past year, have watched,studied, analyz;ed video programs and havecarefully formulated their own entertain-ment ideas and mobiliz;ed the necessaryprogram resources; with a financial andbusiness affiliation with the outstandingproducing organiz;ation in the movie field-with all these trump cards in its hands, hereand now, Du Mont is prepared to maketelevision the outstanding entertainment inthe home, club, hotel, theatre lobby, tavern,and wherever people congregate to passthe time of day.A second television station has been

built by the Du Mont organiz;ation for theWashington, D. C. area. This station islocated at 726 Eleventh Street, N.W. Anantenna 172 feet above the sidewalks in-sures a strong signal throughout the Capi-tal district, from this transmitter operating

at first on an experimental license basis asStation W3XWT.Du MONT SERVES IN THE NATIONAL

DEFENSEWhen our nation was suddenly con-

fronted by a world gone mad with war,and National Defense became a prime need,the Du Mont organiz;ation immediately en-listed in the army of production. In fact,the major portion of cathode-ray oscillo-graphs now being produced by the DuMont company have a more or less directbearing on National Defense needs, forthese instruments are proving indispensablein critical engineering and production acti-vities. Du Mont engineers are constantlyworking with Government services, andwith National Defense contractors, in fit-ting cathode-ray equipment to almostcountless critical problems ranging fromballistics and radio technicalities, to the eli-mination of vibration in aircraft.----~----

And beyond the production of its usualline of products, the Du Mont organizationhas geared up its facilities even to the ex-tent of opening up a second plant buildingprimarily for the production of televisionreceivers, while releasing still more produc-tion capacity in the main plant for specialradio transmitters and receivers called foron Government contracts. The organizationis proud indeed to serve this nation to theutmost of its capabilities.

AND So WE LOOK AHEAD,CONFIDENTL Y

All this, and much more which couldnot be discussed in this limited space, hasbeen achieved in but ten short years. DuMont has rounded out its first decade ofexistence as an organization. Much of theeffort has been by way of foundation build-ing. Allen B. Du MontI the man with theidea, has surrounded himself with a staffof engineers, designers, instrument builders,sales 'engineers, video broadcasters. Sotoday Du Mont means a compact, enthusi-astic, loyal, hard-working group of special-ists intent on exploiting cathode-ray tech-nique to the utmost. How much easier,

During recen.t AnnymaneuverS Du )\1onten.gineers and opera-tors demonstro ted tomilitary men tIle poten-tialities of televisionscouting and reporl.ing.Rigl'l up front. prop-erly camouflaged fromIIw "enemy", IIw DuMont camera and mo-bile transmitter flashedvital graphic reportsback ta IlCaelq'LQrt.ers.

Ti,e cot/lOde-ro)' campass installed in a Coast Guardplane. A special Du Mont 3-inch high-sensitivitytube is u!;pcl in conjunction witll a radio com.possdevice permilling direct bearings to be tal<en or to beHsed (IS a JlOming ,npons. Tube is ahove. with 11lQg-

netic compass, artificial 11orizon, and directio1lo1gyro compass, in vertical line below.

greater, and simply unpredictable, there-fore, must future progress be under suchextraordinary circumstances!

Uu MONTliEY MEN

Thomas T. Goldsmith, Jr., theresearch. coordinator for: alldevelopmental, el1gi1lee-ringandproduction activities. Dr. Gold-smith conducts the technicaldemo'llstrati011S and discus-siml.r. such as those for theF.C.C. officials and the NTSC.

Norman Hall, in charge of themodel shop aud televisiontransmitter production. Hetranslates engineering datai 11 to commercwlly-fea.sible-equ,ipmcnt terms.

Patti Ware, in charge of tele-vision receiver product-ion anddefense con1ro'Ct production.He has also had much to dowith televisioll ·rccci1.'cr cir-cuit developments.

Stanley Koch. ht. charge ofcathode~ray tube prod·uctionfor both tclet'ision a lid instru-ment requirerncllts. A skU/cdglass-blower In, Ids own right,he carries out the id(·QS sentolol1g b)' the engineers, audsu./JenJises all f'roductio"l fromglass blank to final e.t"lIO'Ustand sealing.

Richard Cam..pbcll. ill chargeof ,f!'lcvis'ion transmitter devel.opme/lt. In the field of tele-'l'ision scan-l1ing tecl11liqu.e. heis sccoud to 1lone, and hasdOlle much of the eHgiJleeri11g'work on the Du MO'nt Syn-chromatic Scann-illg System,He is responsible for the tcle-'l'ision units and (ellOins",

Charles Huffma"l. in charge ofthe engineering and operaHonof the Du Mont N eui Yorktelevisi011 transmitter, Sta.tionW2XWV. He has 0" enviablebad.-ground in televiriOt~ pia.1leeri11,g.

P. S. Christaldi, who is direct.Iy ill charge of desl:pH and de-velopment of standard a lidII1'ghly specialized cathode-ray1·'lstruments. Requirementsand problems in tlu's field O1'esubmitted to h.itn for his rec.ommendations and for specialengineering <if·hell11ecessa'''jl,

Harry H01tsten, in charge ofall production activities of theplant. He is the man whokeeps the wheels t1trl1ing, fromthe i-n,coming flO'W of materialsto the outflO1.ving shipmentsof fi/lishecf products.

LeoltQrd F. C;-all'l-er, j'n c/zargeof cathode· ray £;lstrltHWH·taHd tubes, as u'€ll as tele; ..iswatraJlsmitter, sales. He headsthe sr1{es acti,:£ties of Da Jfon;repY:!~~e~ltath t!$ t;!YO'Ug:iOHt 61l!cou)/~r~.,

H. A, C/iHCh, -:.610, as thef'J'llycJla,H~Jlg agent, secltYl!S tilewirfe array of HUlt2rials andf'ayt~~ required for all pro~d;~c;:'o;: actir. itics,

llfark B. LajO'i.'c, i;l charge oftelevision recei:-rer sale.f. Hehas a: backgroulld oj years ofmerchandising experieilce £~~the radio set al1d a·ccessorvfields. He heads the staff ofsalesmen and dealers JiaHd!£H{}telev£s£oH recei:.'crs,

Jli"ss Alma J, /£;I;'(:-;:S, theca.poble office 11uulager '<.l.'lwsllpo':'ise;s f:le c01t..J·iderablecud grou:iug taper work ofthe D!J. .Huilt tJrgaui::ation,rcrn'c;u'ar(, I:::? acco:01tiHg,

Jfortimer lV, Loeu"1' W;:J. G.SGSS;·.}':Oi:; to r;le Presidei~r.wtYr?s u/1'th _',fr, Du JluHr );j

ma"y of r::c? cxec1ltiI'C at'.!fiHa.nciaJ derails or tiu's raf1:·d·ly e,r7Jadil1g o,.ga;zi=t1r:·o;~.

fVill Battin.} Program Dt'rec-to/ of the D" M"nt l';e-JJY&rk teJe"oJiswn s tat~' O·il.

W2XWV. His rich baek·around of television p'ro-duction eXpeyieHCe ensuresercept£ollaJ telecastiug cute.,-·ta;illment.

OfficersPresident ALLE.' B. Dt; ~O~TVice-President _ MORTIMER W. LoEWI'Treasu.rer PAUL RAIBOCRNAsst. 'Treasurer _._..J. J. DOL:G H l 'E YSecretary BERNARD GOODWI>f

ALLEK B. Du MONT

MORTIMER W. LoEWI

PAUL RAlBOURN

BERNARD GOODWIN

ARTHUR ISRAEL, JR.

PHILIP SIFF

ALBERT]. RICHARD

HERBERT G. WELLINGTON

Where flu MONT PRODUCTS

are made ...* An attractive, modern brick buildinglocated at 2 Main Avenue in Passaic,N. ]., houses the general offices, engi,neering laboratories and normal produc'tion activities of the Du Mont organiz,ation. The building is company-owned,having been purchased in 1938 when theorganization moved from its Topsy'growth string of stores in Upper Mont'clair to these far more efficient and dulyplanned quarters.The plant building is surrounded by

spacious grounds, providing for futureexpansion. A side track provides forbulk shipments via the D. L. & W. Rail,road, which passes at the rear of theproperty.In order adequately to take care of

the growing volume of National Defenseorders, while maintaining the necessary

production of instruments, tubes andother standard products, the Du Momorganization has recently taken overanother building nearby. This annex isdevoted largely to National Defense.contract business, and also to televisionreceiver production and conversions tothe new transmitting standards.The Du Mont organization also main-

tains a sales office in New York City,at 515 Madison Avenue, as well as itstelevision station which occupies the en-tire top floor of that 42'story skyscraper.A second television station is located inWashington, D. C., to serve the Capitaldistrict.Needless to say, you are always wel,

come to call at the plant or at the NewYork sales office and television studios.The latchstring is always out.

~. !-r=_c:c.-;" .-! .r---...-...,

Du MONT PATENTS* Thc following are but the patents issued to date and assigned to the Du Mont organization.Due ro the extensive and continued research and engineering activities of the company, newpatent applications are constantly being filed and issued in most instances. The following,therefore, is merely past history.

ISSUED PATENTS.'\I!en B. Du Mont Laboratories, has issued to it the following Patents:

1,844,1171,960,333

*1,999,4072,000~014

"'''2.014,106"'2,067,382*2,082,327"2,085,5762,087,2802,098,231

,',,', :""2,153,8002,157,749

2.163,2562.164,176

2.185,7052,186,634

2,190,020H"Re.21,326

2,207,0482,208,2542,209,5072,221,3982,225,0992,227,822

2,245,4092,245,4282,249,942

Sound Operated Circllit ControllerCathode-Ray Instrument for Measuring ElectricalQuantities

Electron TurbineTela utogra phVoltmeter for Vacuum TubesSynchronous Electron MotorCurrent Generator and ConverterCommutating DeviceCathode-Ray TubeCathode- Ra y DeviceMusical Instrument Tuning ApparatusMethod and System for TelevisionCommunication

Cathode-Ray Cyclographic Bridge BalanceIndicator

Cathode-Ray TubeMethod and System for TelevisionCommunication

CathautographMethod and System for TelevisionComm unication

Cathode-Ray Tube

Mosaic ScreenMethod and Means for Inductively Heating theMetallic Parts of Enclosed Electrical Devices

Method and System for TelevisionCommunication

Television Transmitting SystemAmplifierSynchronizing GeneratorAmnlifierCathode-Ray TubeSystem and Method for TelevisionCommunication

Cathode-Ray Tube Control Device forTelevision Scanning Apparatus

Method and System for Television CommunicationTelevision Transmitting SystemTelevision Systems and Synchronizing meanstherefor

Systems and Methods for Television Reception

Allen B. Du MontAllen B. Du MontAllen B. Du MontAllen B. Du MontAllen B. Du MontAllen B. Du MontAllen B. Du MontAllen B. Du MontAllen B. Du MontLester B. Holmes

Thomas T. Goldsmith, Jr.Allen B. Du Mont

Thomas T. Goldsmith, Jr.Allen B. Du Mont

Allen B. Du MontAllen B. Du MontAlfred J. Hinck, J 1.Thomas T. Goldsmith, J1.

Thomas T. Goldsmith, Jr.Richard L. CampbellWilliam A. GeoheganRichard L. CampbellWilliam A. GeoheganPeter S. Christaldi

Richard L. CampbellAllen B. Du MontThomas T. Goldsmith, Jr.Horace G. MillerRichard L. CampbellRichard L. Campbell

" R.C.A. licensed under these patents.** This patent sold to R.C.A. Du Mont retains rights to 'manufacture and sell under this

patent and also to license in non-radio field.Allen B. Du Mont Laboratories licensed under this patent.Du Mont· has a partial interest in this patent.

--------------------~-----------------

Uu MONT SALES

* Beginning its corporate existence III 1931, primarily as a research andengineering organization, the Du Mont company began actual production andmerchandising activities in 1932. Its rapid sales growth, with 1932 taken asthe 1001'0 basis for comparison, is given in the following percentage figures.In its tenth year of existence this organization, due not only to NationalDefense contracts but also to the widespread demand for cathode-ray instru-ments and television equipment, is attaining fantastic gains which cannoteven be estimated at this time.

SALES1931 3701932 1001'01933 662%1934 1011%1935 2039%1936 38381'01937 5602%1938 5089%1939 6322%1940 95201'01941 (1st 6 months) 41,6501'0

And that, in conclusion, is the climax of a decade of pioneering in a new field.To Allen B. Du Mont, to his close associates and co-workers, to customersthroughout the world, must the credit, fairly divided all around, be due.Certainly the heartfelt thanks of the Du Mont organization go out to itsfriends and supporters and admirers, everywhere.