l conv...special n.a.b. convention number paul v. lutz, editor the corer photograph illustrates the...

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New! Overseas dial. Foreign stations once

shown in 1/4 inch on dial, now given 9 inches.

Easier to tune than domestic.

New! Sonic -Arc Magic Voice! Simplified Tone

Chamber uses "band shell" principle . . . de-

livers "boomless" tone -full performance.

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New! Beauty -Tone Cabinets by Victor. World

largest musical cabinet shop produces superb

new designs in lovely, rare woods.

eerie _ _uning. Push a hutton. . . theres your station

39 nerv1938 models announced/

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Electric Light Button

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Model 813K-An entirely new conception of a radio set. Look

at this big RCA Victor Electric Tuning model. See the sensational

Overseas Dial with its five 9 -inch -wide tuning bands. Note the

button: that tune your favorite stations at the touch of your finger.

Study the lovely proportions and fine lines of its Beauty -Tone

cabinet built to share in creating the tone -full quality of the

Sonic-A.c M3=ie Voice. Thrilling 13 -tube performance. Armchair Control extra.

Millions have been asking for it ! Now RCA Victor delivers it . . . a radio set

with which you can tune to your favorite station by simply pushing a button.

Electric Tuning-truly automatic.

The big open-faced dial is an "overseas" switchboard. You can tune foreign

stations easily. Push a button. and you get your favorite local station. Another

button for another station. And so on. around and among your favorite stations,

as you please! No dialing' No twisting auvthing around ! Just a button to push

-the same as turning on a light in your living room. That's RCA Victor Electric

Tuning! .

Nor is this all ! For a few dollars more you can have Electric Tuning with

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. Model 8511 . _ a smartly fashioned little chest model that will. give you entertainment from all over the world. New type dial simpli-

fies tuning and enhances appearance. Cabinet reveals new and modern uses of fine, rare woods. A' 2 -band; 5 -tube superlíeterodyne of

fine volume and tone. Dynamic speaker, auto-

matic volume control.

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Armchair Contr0L Then you automatic -ally tune the SONIC ARC Magic Voice

fro you: euT_ chair. or even from another room.

Finer Tuning at Every Price

Remember this. too: Th. 1938 RCA Victor Radios offer you a choice among

39 modek_ Weyer you pay. whichever you choose, you will get an instrument

with easier. finer. more exact tuning . . . an instrument that will make radio

entertainment more exciting. more interesting.

It is worth while to hear these new RCA Victors at your dealer's. and

to learn about his liberal trade-in allowances. You will discover that RCA Victor

experience creates finer radio sets, that cost no more to buy.

BROADCAST NEWS BROADCAST NEWS

REG. U. S. PATENT OFFICE Your Logical Choice

RCA Tube economy is no longer news

to broadcasters who have found that RCA

Power Tubes mean lower operating costs

and more satisfactory service.

Take, for , example, the RCA 100 kw.

tube. Many 50 kw. stations have found that

this tube, the 862, is one of the most satis-

factory and economical ever built.

Whether your station is 100 watts or

50,000 watts, you will find RCA Power

Tubes lower in operating cost and uni-

formly satisfactory.

RCA

Radiotrons

RCA MANUFACTURING COMPANY, INC.

CAMDEN, N. J.

-4 Service of the Radio Corporation of America

JUNE, 1937 - - No. 25

Special N.A.B. Convention Number

PAUL V. LUTZ, Editor

The corer photograph illustrates the construction of a high power tank coil.

PAGE

Building a Transmitter 2

Map of Installations 15

Listeners 16

Letters from Listeners 17

Tubes 18

Station Buildings 19

Speaking of Pictures 20

In the Future 22

Equipment 23

1 EASTERN DISTRICT-Ben Adler, Manager, 1270

Sixth Ave., New York City; R. P. May, Assistant.

2 CENTRAL DISTRICT-A. R. Hopkins, Manager, 589 E. Illinois St., Chicago, Ill; R. A. Wilson, Assistant; A. Josephson, Assistant.

3 WESTERN DISTRICT-W. H. Beltz, Manager, 170 Ninth St., San Francisco, Calif.; Edmund Frost, Assistant.

4 SOUTHWESTERN DISTRICT-W: M. Witty, Manager, 2211 Commerce St., Dallas, Texas.

5 SOUTHEASTERN DISTRICT-D. A. Reesor, Manager, 490 Peachtree St., N. E., Atlanta, Ga.

LONDON ENGLAND-B. Gardner, European Man- ager, Radio Corporation of America, Electra House, Victoria Embankment.

Photographs in this issue are by Alfred A. de Lardi, F.R.S.A.: Norman Newell; H. S. Attmore; J. O.

Gaynor; from the National Broadcasting Co.; the Columbia Broadcasting System; from radio station WMBO as well as from other stations.

Published in the Interest of the Radio Broad-

casting Industry and Copyrighted, 1937. by the

RCA MAINUFACTURING CO., Inc.

CAMDEN. NEW. JERSEY. t-. S. A.

Finest Electrical Transcriptions

is RCA Victor... Sound

Recording Leader!

HE RCA Victor Company, world's leader THE sound recording, has always played an

important part in sound reproduction. Its years

of experience, great laboratory research, record-

ing and record making facilities are all avail-

able to you. And yet this premium service costs

no more than ordinary electrical transcriptions!

RCA Victor electrical transcriptions offer

many exclusive advantages. The patented RCA

Victor "Higher Fidelity Process" of recording

enables RCA \ ictor to record every note-from the extremely high to the deepest bass. The

entire musical range is heard in exactly its

original timbre and color. RCA Victor electrical

transcriptions are particularly free of record

scratch . . provide adequate volume at all

times. They are made of " Victrolac," a flexible

material extremely resistant. to wear and warp-

age. Because of their light weight they may

be mailed at extremely low cost.

The RCA service also offers you the benefits

of RCA ALL THE WAY. For through its asso-

ciation with every phase of radio and sound re-

production RCA Victor not only can assist you

in building shows but has experienced Victor

and NBC artists at its service. For your conven-

ience RCA Victor electrical transcription studios

are located in New York, Camden, Chicago,

Hollywood and Montreal, and the one nearest

you will be glad to give you further information.

electrical - l-C'akaeCl,(ittl,Gtiid

RCA MANUFACTURING COMPANY, INC.

Camden, N. J.

A Service of the Radio Corporation of America

TRADEM ARKS RADIOTRON AND ICONOSCOPE

REG. U. PAT. OFFICE BY RCA MFG. CO., INC.

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1. A Conference is the starting point for the new transmitter. Here, in the office of I. R. Baker are gathered representatives of the engineering department and the sales group to discuss what is needed and to lay out a schedule of

FROM SKETCHES TO FINAL TEST

A TRANSMITTER IS BUILT

"CONSTANTLY IMPROVED BUT NO YEARLY MODELS" WAS ONCE THE SLOGAN OF A MOTOR CAR MANUF 1CTURER. IT MIGHT WELL BE ADOPTED BY RCA MANUFACTURING'S TRANSMITTER SECTION BECAUSE, ALTHOUGH SUCCESSIVE PRODUCTIONS OF BROADCAST TRANSMITTERS CONTAIN CURRENT IMPROVEMENTS, MODELS ARE NOT OFTEN CHANGED AND PURCHASERS WORRY LESS ABOUT HAVING BEHIND -THE -TIMES EQUIPMENT.

NEVERTHELESS WHEN IMPORTANT IMPROVE- MENTS CAN BE EFFECTED, A BRAND NEW MODEL

TRANSMITTER IS OFFERED TO THE BROADCASTING INDUSTRY. A CASE IN POINT, THE NEW 250-D

MODEL, INTENDED FOR HIGH FIDELITY 250 WATT SERVICE OR AS A BASIC EXCITER FOR HIGHER POWER TRANSMITTERS IS FOLLOWED THROUGH THE PROCESS OF DESIGN AND PRODUCTION FOR

TF:E BENEFIT OF THOSE WHO HAVE NOT VISITED RCA'S FACTORY.

2. Doodles resulting from the meeting often reflect random thoughts as we I as notes to he studied further. Famous men find

doodling a help to concentration. Engineer's doodles. like these,

are apt to he somewhat technical.

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progress. Usually the engineers come with a number of ideas for improvements and these are gone over to see whether they will conform to the re-

quirements of service.

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SALES, ENGINEERING, STYLING, CONTRIBUTE TO THE TRANSMITTER DESIGN

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4. John Vassos, well known industrial stylist and illustrator with Lynn lirodton go over the plaits and

provide an external design which will be Loth pleasing sold functional. Styling is today recognized as

important from the standpoint of usage and prestige to the buyer.

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3. Letters to district offices °nob.. tie tlrieln,seel design

and require prompt answer for criticism and suggestions.

lil::1's district transmitter sales representatives ale all engineers, appreciate the technical problems of broad-

casting stations. are able to cheek the design fr the

standpoint of the user. From close contact erith stations

they ad, for and get a design which the station: would

approve. Here, lien Adler in New York goes over the

letter and prep:ue: to reply.

5. Engineering discussions are frequent. The man in charge of the transmitter is in constant touch with

other engineers specializing in such fields as power supply equipment. mechanical design. filters. etc.

Sketches of the equipment are made showing the outline and the relative placement of parts.

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6. Laboratory models are often built to check operation of circuits and arrangement of parts. No particular attention is paid, at this time, to external appear:une since the circuit model usually hears little physical resemblance to the fin- ished equipment. Measurements on circuits provide checks on calculations and prevent possibility- of errors.

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7. The model shop is a factory in miniature. concentrating on doing things in a smaller

and better Nay. Here the model of the transmitter is made, with all of the parts

complete. While the components are made without production tools, production problems

are studied so that manufacturing costswill he minimized. In this shop also, small

quantities of special equipment are manufactured.

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8. Handwork by skilled artisans is an essential operation in the preparation of the model.

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9. The model transmitter is sent to another building, removed from the rest of the plant so that its operation will not interfere with tests and measurements of a

sensitive nature being made in laboratories. Power is

applied and careful checks are made on the efficiency, fidelity, ease of operation and reliability. If improvements are discovered at any point of the procedure, they are incorporated in the design.

10. Appearance not important at this time, and front panels

are usually omitted. being replaced with wallboard for safety.

The equipment is fed into a dunnny antenna simulating alt

actual antenna. Tests on the model often last several week

and after the engineer is satisfied that every detail is correct,

manufacturing drawings are e pleted for use of the factory.

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12. Curves and notebook data are carefully preserved for reference. The slide rule, the curve and the notebook form symbols of the work of engineering.

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COMPLETE DATA ON MODEL

INDICATES PERFORMANCE

11. Laboratory measuring equipment including osrillographs, %%aye analyzers. low distortion oseilkiturs and other apparatus proside- complete operating data on the model transmittet

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13. Model work completed, the drafts- men start manufacturing drawings. Drafting is often carried out in the building where the model is set up so

that actual measurements can be made to supplement sketches from which the model %%as constructed.

VIEWS OF THE FACTORY CAUGHT BY THE CAMERA

The factory begins work. Simultaneously in many shops, work begins on the components of the transmitter. Detailed drawings are supplied for each component and

carefully planned production reduces manufacturing cost..

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14. Rust protection important. Frames, metal panels. shields. all are 15. Tool work on other units progresses in RC.\'S well equipped shops. Precision workman.

rust -proofed before applyiug final finish. Here in the copper plating shop. ship and engineering supervision assure proper operation of the complete transmitter.

components are receiving a protective coating.

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16. In the factory workmen at machines and men en cased in masks fabricate the parts. Welding of

frames produces a sturdy construction, well able to units of the equipment. Sandblasting of frames and

withstand transportation as well as to support the panels assures a clean, firm base for lacquer finishes.

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17. Production lines are not used for transmitter manufacture but are limited to alas production of units. such as auto-

biles. radin receivers or refrigerators. Most parts for the 250-1) are hand fabri- cated by skilled machinists.

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18. Other components manufactured in RCA 'S plant begin to arrive in the factory types of ,transmitting equipment are important circuit elements. Types of con -

awaiting assembly. Faradon condensers, built by RCA and cued generally in all densers like these go into the 250D.

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19. Raw materials and parts manufactured by specialists are now ordered by the purchasing department. While RCA makes most radio parts in its own factory, standard con-

tactors, resistors, meters and similar components are ordered on rigid specification. Above, the purchasing agent goes

over the parts list with a manufacturer's representative.

20 Before assembly can start all of the material needed must he in the factory. Thus parts made in the various shops in the RCA plant and components from outside man ufacturers begin to arrive and are piled on benches for mounting in the transmitter frame.

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21. Contactors, transformers, switches, relays and all of the materials have now been delivered to the factory. Parts received from the outside have been carefully inspected and tested in a special laboratory to make sure that specifications have been met.

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THE TRANSMITTER BEGINS TO

TAKE SHAPE

24. After a final spray of aluminum paint on interior metal surfaces, the components are bolted in place on the chassis.

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25. The vertical chassis assembly of the 250-D

simplifies adjustment and maintenance by ren-

dering every portion accessible. The two L

shaped chasses, with parts assembled, are bolt-

ed together, mounted in frames, and mired. The

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22. Mechanical mountings are completed first as this view of the radio frequency

chassis indicates.

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outer cabinet is for protective and decorative purposes only. The inner frame bears all of

the stresses just as in modern skyscraper construction. At the left, the r.f. chassis is in the frame, on the right, both are in place.

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23. Skilled wiremen next take over the equipment, put and insert the other individual connections.

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the cable forms in place

PERFORMANCE TESTS CHECK TRANSMITTER

OPERATION

26. Construction completed the transmitter, less outer shield and doors, is moved into the test cage. Here wiring is checked, and the equipment is operated with full power and with reduced power (to check 100 watt service) into a dummy antenna. Performance is checked with elaborate measuring equipment.

. Complete fidelity curves are made on each transmitter.

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21. Individual test booths with separate measuring equipment permit several transmitters to be testci at once.

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30. Wave analyzers are employed to

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-m 28. A power change switch is useful for changing from 250 to 100 watts for stations operating with reduced power at night. Correct functioning of each device is carefully checked.

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29. Transmitters are tested with actual tubes from stock, not selected tubes. Final measurements are made using the tubes sold with the transmitter.

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measure distortion and to make certain fidelity of transmission is well within the rigidly specified limits.

"V" CUT CRYSTALS ASSURE FREQUENCY STABILITY

In the meantime, the VCnt crystals are being made. ground to the frequency of

the particular station ordering the transmitter. The natural mother crystals,

received from Brazil, are carefully examined for regularity of crystal formation.

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31. The polariscope aids in examining all quartz to determine whether crystal 32. The mother crystal shown exhibits "needling," which makes it unsuitable to meet

structure is suitable. "Twinning" as shown in the above illustration renders the RCA's specifications.

%lank unsuitable for use.

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33. Thickness faugis indicating ten -thousandths of an inch aid m"paeparation of the quartz for final lapping.

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34. Grinding of blanks is carried out on special machines by trained workers.

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35. The X-ray is used also for examination of crystals and study of crystal 36. Holders must be carefully built. Metal electrodes are carefully lapped and

polished to optically flat, uniform surfaces. structure to insure reliable operation.

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37. Crystal units contain the crystal, its holder, the heat chamber and thermostat. Two of these plug-in units are used in the 250-D transmitter. RCA Vcut (low

temperature coefñcient) crystals, beaters and thermostats provide stable, accurate

control of carrier frequency.

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39. Elaborate test equipment shown above in the shielded cage is

necessary to check the crystal frequency as well as the electrical

40. Testing thermostats. This machine marks on a roll of paper whenever the heat is applied to characteristics. Accuracy of this apparatus must be of the highest

the crystal oven. Eight heater units are tested simultaneously. order.

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and tested by the most modern sod

scientific methods and foond to be

as sh ,tied fro© the feetory satisfactL' ¡t ) ,'V`

43. Constant inspection at each stage of manufacture is

added assurance of satisfactory performance. The final tag

is fastened to the transmitter and the equipment is ready for packing.

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41.".Finishing side strips. Careful attention to details, hand rubbing of panels and style strips and improved lacquers assure a pleasing appearance of the equipment.

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42. Completed and ready for final inspection. The 250D is

almost ready for packing.

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44. Ready for shipment. Skilled workers crate the apparatus to avoid damage during whatever method of transport the buyer desires. While careful packing is a small

transportation and to make for easy handling. The transmitter is delivered by detail, it is important to the purchaser.

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At WMBO in Auburn, New York, the 250.D is set up and connected to external wirint_ RCAs Engineer. James Keachie assists Herbert J. House of WMBOin the final adjustments.

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The new 5-D transmitter which also employs the 250-D as the exciter.

As shown above, the 250-D transmitter has now been completed and installed at WMBO. If the owners of this station should wish to increase poster, they can add a standard 1000 watt amplifier to form the 1-D equipment shown at the right, or a 5 kw. amplifier to produce the 5-D equipment such as that illustrated above.

Front microphone to transmitter. RCA equipment is complete. Modern broadcasting stations are RCA ALL THE WAY- to assure themselves of the latest and most reliable broadcasting equipment.

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On the air and ready for a long broadcasting life. The completed transmitter is started on regular broadcasting service.

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The 25e -D may also be used as an exciter for 1 kw. equipment. Thus stations obtaining an increase in power may add to existing apparatus without discard- ing equipment.

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Many prisons are equipped with radio. and convicts Scenes like this warm the broadcaster's heart. The Foreign listeners become more important. This mem-

a e said to he enthusiastic listeners. Needless to ,ay. number of listeners to any one set is indeterminate her of the radio audience, seems to derive much

travel programs evoke little response. but every station hopes to pull groups like this. enjoyment from the program.

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The radio set manufacturer's idea of the radio listener is often like the above photograph.

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LISTENERS

Broadcasting Stations exist primarily for the listeners. Skilled research bureaus constantly strive to classify the radio audience, study its habits, predict its likes and dislikes. Broadcast Neu's, rushing in where angels fear to tread,

presents views of listeners caught at the listening post.

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Old as well as young enjoy radio. Broadcasters have the satisfaction of having brought pleasure and entertainment to millions. Old sets, such as the one on the

right may still be found in existence occasionally.

LETTERS FROM LISTENERS

A CROSS SECTION OF HUMANITY, WITH ITS TROUBLES,

ITS PLEASURES AND ITS PROBLEMS e

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w. I ..tonlNed, when I if handing on Ile wed., type P. awing up. fad wt. the .IC le helping a to do It. awe, It we grad. I we WOW) awry .hen they sot' through.

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Couldn't loo 0.M re u. ow It' .sate .tee .1 a actor, or 0.M

yin as end a se , Wind 01100 t woe of

We ...t There et be plenty ofd wee to la' Wse. Tea w ouldn't newt .,thing .toe. Jurt . , and end W. .01.peers I bed. w.., I newt appreciated hi.. le w. 1e, net Co .,e print to a, lest a en0,1loaretinn Of high-rlotlo .end Welled out a paper. gel that tan, .hat In Is, .t 011. g. le ratty one blot teat delta out to eater a wt. I trl.d M reed hie. I awe bee wee 1 RAP nle I too..

1\yt.neaw west wow are 11 elite. last .inter doe eight I'e .ire vo' there beside tan radio reading od.hwa. and euddrol3 the toot felle out of w Up end Ire flyln through Tae., gala den w

awetnd little firth. tenting a 'sport -anti, en its .01., to 'halo cant flooded .00b 0114 apereoe.1 wee.Itate and a thl.tst e herd ee sir I can 'You .re . 'negating ting little Start, one ee get r1ól dew to the truth about It. srot you. and rowing not to be ill. that ay are. al .grow wife tea now the w It as en old coot aa: batbown, .nd the plow I. called 'The %penlight goals . fee I

.. '0,11 IM big -Ito 0..l., and I .s tell its so t«' and roe ewe ear. .al did W. Wetwrw bold, es' I .we "Be Ella. .. thing. W W11 ita e. didn't Wars .004 I .id' and .he 101 'Ow w Onnt yew ewe Msthoeee w deaf 00 a poet.' MI I w -'.11 T's glad 1

t Due If a we dour how did he too. It wind .010.7 lite thet0' tnd .re Waal at ee 0101. pityingly. he ~ 1.. gainful to y0,. I here only one 00 1o1at le

1'. »elf! de 70. be -p on Writing those late teeds late w boo.., .wen

tiled awn fo, 0.1er .wninet The euaear. d..'t li.e le olat-cl-be. s. lose .t how. w Jinn W oft a rat ewe to rela. lt:eL alwellee.cu. hailer). Jet I. alright, with eau of pretty . ;-1.7104 dam the .1.14 th tight., .el .011110' Wawa.* on year blue .Olt. ti: a *late would be out of plate, we .euldot they. deed le. Waled 11101. Gerald:. w 'ya t led 14'1 .td lava L Wig yteoe, the as w. Luau. hew I. the place we W Wee 7eu ere

.: of 0.101{ 1431. That. t you add 1 beep en alibi the vent. it a +r 1Y ever Far es* n 00100. Btncersy

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The problems of radio are not all of a technical nature. Listeners have personal

problems which become radio problems through the simple method of placing

the onus for their solution on the station. But among the letters received are

many genuinely appreciative of the service being rendered their vast, unseen

audience by the radio stations throughout the country. Above are shown a few

interesting letters received by NBC.

ALL BROADCASTING

DEPENDS UPON TUBES

It is inconceivable that broadcasting could exist without vacuum tubes. The supplying of poner tubes to broadcasting stations is one of the function- of RC %. Once tube sere non -uniform, handmade; like those shown at the loner right. Today, modern production methods and elaborate equipment enable tubes, such as the RCA -805 at the right, to be manufactured uniformly and reasonably.

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141, Inserting a heater cathode in the element assembly of an RCA 837. Great care is exerted in applying the active material to the cathode surface to retain exactness of the coated area and thickness.

- *

Exhausting a transmitting tube. During the process the elements are heated to release gas. In this picture the plate is operating at a temperature of about 2500° F. More than 16 kw. power is used in the heating of the metal parts.

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High frequency measurements on tubes provide valuable data on performance and are often the forerunners of important tube developments.

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curb tube

pcod"cc a.

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Early exparimenters made tubes out of old lamps and other available parts. Such tubes were usually soft and no two had identical characteristics.

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Above we find the antenna of station KTSM rising from the top of a city office building.

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KARK is far removed from the city limits.

STATIONS HERE AND THERE

In the short span of 15 years many changes have been made in the method of housing transmitters. In earlier days any factory building or warehouse was

considered quite good enough for the equipment in broadcasting. Today, throughout the country functional design is considered imperative.

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Above, not alone in the buildings erected for transmitters is there a trend towards

beauty but here at WK\ we find landscaping which is extremely pleasing.

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KTOK

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KTOK adopts a simple and pleasing design for its transmitter home.

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Above, KRBC uses a building of plain, almost severe lines as the station for its equipment.

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Above, WGST is decidedly modernistic in the construction of its transmitter house.

Left, WFAA with its modernistic home, beautiful grounds and antenna,

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RCA's first broadcasting station. A one -day affair used for broadcasting the Dempsey- Carpentier fight, located at Hoboken, N. J. Using an antenna tower which is still standing on the property of the Lackawanna Railroad. Station used in July; 1921.

An 1897 complete coil and Lectors.

radio station with spark coherer de.

The predecessor of KDKA, Dr. Frank Conrad's transmitter located in his garage, which later became the first regular broadcasting station in the United States.

An early antenna erected at Poldhu, England, for Trans -Atlantic com nlunication in 1901. Unfortunately these towers blew down before the test, and a temporary antenna was actually used.

.

Page 20

SPEAKING

Radio communication is only about 40 years old. broadcasting, little more than 15. Photographs on this page indicate the equipment and meth. ods used in the early days of wireless and of broadcasting.

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In the studios of WJZ, Newark, 1921, a reception room in the factory was verted into a studio for one of the early broadcasting stations.

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Later. Technique had developed to the point where sound effects were an important part of broadcasting. Note the varied methods of producing noise.

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OF PICTURES

In contrast with old pictures are -ho-n phis.- graphs of new apparatus and present methods

of broadcasting. advances during the 13 years

of broadcasting have been far reaching.

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_ `; . hjr [ahl',,-511_1-1 o , Two modern studio installations.7Rl Above, NBC's 8H, the largest studio

in the world, in Radío Cíty. Belo.., a CBS playhouse studio where

invited audiences watch some of the larger programs.

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A modern short wave transmitter. The 10KW RCA International Broadcast Transmitter at W2XE, Wayne, N. J. used for sending CBS programs abroad.

Sound effects the modern way. Records supplant many of the earlier devices and

few of the old noise -making machines are necessary.

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A modern 5 KW transmitter installation at KOMO. Compare this with the transmitter pictures shown on the opposite page.

A modern antenna. Steel vertical radiators have improved efficiency; are

used generally by broadcasting stations. The WABC antenna was one

of the earliest vertical radiator installations.

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IN THE FUTURE - Television Broadcasting may someday he a reality. When, "e do not know. Today, RCA engineers study apparatus problems at Camden while experimental programs sent from W2XBS to groups of observers enable NBC to study program and studio technique. At the left-the Iconoscope and the Microphone- symbols of television. Belo", left - the tele-

vision control room in Radio City; part of the Empire State transmitter control room; the rear view of a synchronizing generator panel.

Below-transmitting a fashion show by. television-the makeup man works behing the scenes in the studio.

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.Page 23

A FEW OF THE RCA BROADCAST EQUIPMENT UNITS

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16-A Speech input consolette features facilities for handling two studios, transcriptions and remotes,

provisions for monitoring, selective talk back and auditioning.

41-B Preamplifier- The link between the microphone and mixer. Used by networks and leading

stations.

41-C 3 -Channel preamplifier One of RCA's new deluxe units.

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40-D Program amplifier features new peak reading volume indicator meter.

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46-B 4 -Channel balanced mixer with input keys, new, large, comfortable knobs.

RCA Broadcast equipment includes all of the apparatus nec-

essary in the station from the microphone and studio equip-

ment to the transmitter. Measuring apparatus of all types is

available for the convenience of engineers. The only manu-

facturer to supply all of the apparatus used in the entire

broadcasting system, RCA has adopted as an indication

of its wide scope. the slogan, signifying the coordination

of de-ign.

RCA ALL THE WAY

t The 44-B Velocity microphone-recognized by the broadcasters for its high fidelity and dependability.

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A new mobile ultra high frequency transmitter of 15 watts power for broadcast pickups. High fidelity transmission, crystal control.

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A new a.c. operated heat frequency oscillator with unusually low distortion for fidelity measurements. Type 68-A.

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58-A Tri-amplifier An economical three -channel preamplifier complete with mixing and switching facilities.

74-B Junior Velocity Microphone -An extremely popular unit.

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77-A Unidirectional Microphone makes any studio better.

-. Typical operator's console This one is used with 78% Speech Input.

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The 78- Speech Input (above) although extremely low in price employs standard broadcast panels and is readily adaptable to future expansion.

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The 250-G Transmitter (above) provides high fidelity operation at low cost for 250 watt stations.

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75-B Field Intensity Meter-Standard for the broadcasting industry.

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69-A Audio distortion meter measures both hum and distortion over 50 to 7500 cycle range. 15-C Meter Panel-indirectly illuminated meters- easily replaceable lamps.

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AVOID THIS: Drifting Is .Serious luint

Let IiCA V 1e(lurn(\- AIea-urin`T Service hell)

\'1111 111i1111ti1111 \-11111' il.-sIr'11etl frequency

For Routine Service Apply at the Nearer Office

Commercial Department

New York, N. Y.

66 Broad Street Phone: HAnover 2-1811


San Francisco. Cali!.

28 Geary Street Phone: Garfield 4200

For Ernergency Service Phone (Open Day

Riverhead, N. Y.

Riverhead 2290

W. U. Telegraph Only Rlverl.ecd, New York

or Wire the Nearer Laboratory and Night)

Point Reyes, Calif. Phone: Inverness 9.W W. U. Telegraph Only

Point Reyes Station Marin Co., Calif.

R.C.A. COMMUNICATIONS, Inc. A RA:10 C3=ORATION OF AMERICA SERVICE

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AVOID THIS! Drifting Is Serious Business

Let RCA Frequency Measuring Service help you maintain your assigned frequency

For Routine Service Apply at the Nearer Office For Emergency Service Phone or Wire the Nearer Laboratory (Open Day and Night)


New York. N. Y.

66 Broad Street Phone: HAnover 2-1811


San Francisco. Calif.

28 Geary Street Phone: Garfield 4200

Riverhead. N. Y.

Phone: Riverhead 2290

W. U. Telegraph Only Riverhead. New York

Point Reyes, Calif. Phone: Inverness 9-W W. U. Telegraph Only

Point Reyes Station Marin Co.. Calif.

R.C.A. COMMUNICATIONS, Inc. A RADIO CORPORATION OF AMERICA SERVICE

.. RCA Tia

High Fidelity Broadcast Transmitters, 100 watts to 500 KW

Ultra High Frequency Transmitters

Mobile transmitters and receivers

Microphones for Every Purpose

Microphone Stands

Mixers

Monitoring Amplifiers

General Purpose Ampli- fiers

Pre -Amplifiers

Program Amplifiers

Line Amplifiers

Portable Broadcast Am- plifiers

II, 01.41

Frequency Monitors

High Quality Station Monitoring Equipment

Complete Studio Installa- tions

Modulation Indicators

Portable Remote Pickup Equipment

Transcription Turntables

Instantaneous Recording Equipment

Sound Effects Equipment

Field Intensity Measuring Equipment

Beat Frequency Oscilla- tors

Cathode Ray O s c i l l o -

graphs

Transmitting Power Tubes for Every Purpose

l conv...special n.a.b. convention number paul v. lutz, editor the corer photograph illustrates the...

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