Community Survey Tips Digital Logic Basics Phase Monitor Update · 2019-07-17 · Land Mobile Activity in UHF TV Spectrum Space Both the Bell System and Motorola have unveiled ambitious

the technical journal of the broadcast-communications industry

Community Survey TipsDigital Logic BasicsPhase Monitor Update

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W dd\ yQ~ '()ick upsound Withbut nols~ ,_ ;: :; '; -

Pipk up: the·n,ew REand:the·new1RE85quiet microphones.

8 Introducing two microphones that~ aren't "rnicrophonic". That areunexcelled for hearing air-borne sounds,but shrug off contact noises. The newhand or stand RE50 and the lavalierRE85 dynamics.

Small, light, and just barely larger thanthe smallest microphones of their type.Yet both use a unique double-wall construction that is more effective in reducing microphone noise than any other wehave tested.

Let's look into the RE50 first. A cutaway shows that inside each RE50 nestlesthe familiar 635A, case and all. It's shockmounted at top and bottom to the outercase. Even the connector is isolated fromthe actual microphone. And the problems

aGuitan

Model RESOomnidirectional dynarr.ic $77.10. Model RESS Ievel+er dynamic $85.50. Suouested professional net prices.

of mass and resonance have been workedout (with the aid of our computer) sothat contact noises and cable rustlingnever reach the Acoustalloy* diaphragm.

The result is remarkable isolation fromall but air-borne sound, even in hand-heldapplications where microphone movementis uncontrolled. And when you add theextra protection of the built-in Acoustifoam" blast and pop filter, this is one ofthe quietest omnidirectional microphones

you can find. Yet response,output level, and polar pattern are essentially the sameas the 635A (one of the mostpopular professional microphones of all time).

But if noise can be a problem withhand-held and stand microphones, it isa plague to lavalier types. Clothing rustle,cord noise, and accidental contact withhard surfaces are common troubles ..Ex-

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cept with the new RE85. Again, we havecreated a microphone within a microphone. But we've gone even farther. Aspecial low-noise grille, for instance. Andeven the hard, smooth paint finish waschosen to reduce small rubbing noises.

The result is virtually noise-free operation even with inexperienced performers.And at no expense to sound quality. Likeall E-V lavaliers, output of the RE85 ispeak-free and natural. Each RE85 comescomplete with neck cord, tie clip, and abelt clip to help control the cable. TheRE50 is supplied with a Model 300 standclamp.

Both the RE50 and the RE85 are nowavailable at your E-V microphone headquarters. In this noisy world, it's a reliefto know that help has quietly arrived.*E-V Trade Mark

a GULTON subsidiary



t____ -·-·

NEW ANTENNA f OR CARS BANDAndrew hasdevelopeda new seriesof economical andversatile antenna systemsfor use in CARS band localdistribution systems. An optional rear mounted enclosure allows rnourrtinq of radio equipment directlyon the antenna or on the tower. When mounted onthe back side of the reflector, the complete RFassembly, including feed can be readily removed formaintenance without disturbing antenna patlh align-

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For further information write for Bulletin 1051A orcontact your Andrew SalesEngineer.

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July, 1973•Volume15, No. 7

BROSDC&ST eoo1neeR1nGThe technical journal of the broadcast-communications industry

iii#tila...

18 Color Camera Basics, part 1 of a series. First of atwo-part series that discusses color cameras from one tofour tubes. Includes facts on design and operationalaspects of cameras. Joe Roizen.

26 Let's get going on that community survey. Guidelines formaking the survey Jess painfull. Includes tips on how toget the survey going and how to conduct the interview.Pat Finnegan.

32 Basic digital logic review. First part of a series designedto till the gaps in currently available information on thebasics of digital logic circuits. John M. Lee.

40 An update on phase monitors. Last part of a series oninterpretations of the FCC's dockets and rulings onphase monitors. Bob Jones.

44 A report from Montreux. Report from the scene of therecent international television symposium.

rDEPARTMENTS

Direct Current .4Letters to the editor 8Industry News I ISBE 14Cable Engineering CE-IEngineer's Exchange . . .. 39Book Reviews .47People in the News 48New Products SOTech Data .......•...... 59Classified Ads 63

\... Ad Index 63

ABOUT THE COVER

Pickup tubes are just a partof the meat for a specialreview of state-of-the-artcolor cameras and their systems. See article on page 18.Photo courtesy of Joe Roizen,Tclcgcn.

Copyright, 1973,Howard W. Sams& Co., Inc. All Rights Reserved:Material may not be reproduced or photocopied in any form without written permissionof publisher.

2

®

EDITORIALRONALD N. MERRELL, DirectorCARL BABCOKE, Technical

PAT FINNEGAN, MaintenanceHOWARD1'. HEAD, FCC RulesROBERTA. JONES, FacilitiesWALTER .JUNG,Solid State

ANDRA BOYLE, Editorial AssistantH. G. ROESLER,Cartoonist

WEBB G. STREIT, Graphic DesignerJOE ROIZEN,Video

ARCHERTAYLOR, CATVEDITORIALADVISORYBOARD

LES NELSON, ChairmanHoward W. Sams & Co., Indianapolis

CIRCULATIONEVELYNROGERS,Manager

ADVERTISINGE. P. LANGAN, Director

R. JACK HANCOCK, ManagerFRANCESSIGMAN, Production

JAKE STOCKWELL, Sales

REGIONALADVERTISINGSALES OFFICESMICHAEL KREITER1014Wyandotte St.

Kansas City, Mo. 64105

lndlanapolls, Indiana 46206ROY HENRY

2469 E. 98th St.Tele: 317/846-7026

New York, New York 10017STAN OSBORN

60 East 42nd StreetRoom 1227

New York, N. Y. 10017212/687-7240

Los Angeln, CalllomlllRICHARD BOHEN

3600Wilshire Blvd., Suite 1510Los Angeles, .california 90005

Tele: 213/383-1552

London W. C. 2, EnglandJOHN ASHCRAFT & CO.

12 Bear StreetLeicester SquareTele: 930-0525

Amstardllm C. HollandJOHN ASHCRAFT & CO.W. J. M. Sanders, Mgr.for Beneluxe & Germany

Herengracht 365Tele: 020-240908

Tokyo, JapanINTERNAtlONAL MEDIAREPRESENTATIVES,LTD.

Shiba-Kotohiracho, Minato-kuTele: 502--0656

BROADCASTENGINEERING is publishedmonthly by lntertec Publishing Corp.,1014 Wyandotte Street, Kansas City,Missouri 64105. Telephone: 913 888-4664.

BROADCAST ENGINEERING is mailedfree to qualified persons engaged incommercial and educational radio andtelevision broadcasting. Non-qualifiedsubscriptions in the U.S. are $6.00 oneyear, $10.00 two years, $13.00 threeyears. Outside the USA add $1.00 peryear to cover postage. Single copy rate 75cents. Back issue rate $1.00. Adjustmentsnecessitated by subscription terminationat single copy rate.

Controlled Circulation postage paid atIndianapolis, Indiana.

I~ Robert E. Hertel, Publisher

INTERTECPUBLISHINGCORP.Subsidiary of HOWARDW. SAMS & CO., INC.

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DIRECT CURRENTFROM D. C.July, 1973

by Howard T. Head)

Private Funding Authorized for Cable Advisory Committee

In an action believed to be the first of its kind, the Commissionhas authorized the Cable Television Technical Advisory Committee(CTAC) to solict private funds to be used for administeringcertain Committee activities. CTAC was established by the Commission in the Spring of 1972 to provide advice with respect tothe formulation of technical standards governing the operationof CATV systems.

CTAC is made up of nine panels, representing various aspects ofcable technical standards. These panels are staffed by volunteersfrom the cable and broadcasting industries. The funds to besolicted publicly will permit the establishment of a WashingtonHeadquarters which will include a fulltime Executive Secretaryand administrative staff.

Land Mobile Activity in UHF TV Spectrum Space

Both the Bell System and Motorola have unveiled ambitious plansfor the use of portions of the newly-assigned spectrum spacenear 900 MHz for a mobile telephone service. The Commission inDocket #18262 reassigned TV channels 70-83 inclusive, togetherwith additional spectrum above 890 MHz, to the land mobile service(see 7/70 D.C.). The Bell and Motorola plans are similar in thatlarge metropolitan areas are to be broken down into smallcellular structures, permitting reuse of land mobile channel pairsat relatively close spacings. Computer techniques are to be employedfor switching and hand-offs between cells. Both companies haveconcluded that the 900 MHz region is suitable for land mobileservice, and that reasonably priced equipment can be mass-producedwithin a suitable time period.

Actual use of this portion of the spectrum for land mobileoperations must await a Commission choice among competing plans.In the meantime, UHF TV translators operating on channels 70-83will be permitted to continue on a non-interference basis withthe land mobile service, although no new translator assignmentsare being made above Ch. 69. Considering that most TV translatorsare in remote areas, and that initial land mobile operation willbe concentrated in the large cities, it seems likely that translators on these channels will enjoy a substantial grace periodbefore their re-assignment to lower channels becomes necessary.

In another land mobile action, the Commission has proposed somereadjustments in the allocations to the various land mobile

4 BROADCAST ENGINEERING



Ain\ nobody else cangive you an S/N ratioup to 72 dB. Nobody.

We call it the Scully 280-B ProfessionalRecorder/Reproducer. Not a very fancyname. But it's so new, we haven't hadtime for anything else but a number.

Briefly, here are the high points, newelectronics for up to 72 dB S/N ratio onfull track .25" tapes. And a greaterdynamic range than you've ever beenused to.

Two-track quarterinch and four trackhalf-inch 280-Blays on a crisp, clean69 dB on anNAB weighted basis.

We've built in some other choiceTM

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The spec sheet has all the details.

For moreinformationcontact your

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Scully/Metrotech.

July, 1973For More Details Circle (6) on Reply Card

5



(Continued from page 4)

services in the 470-512 MHz band shared with UHF TV broadcasting(see 8/71 D.c,.) • Available assignments have essentially all beensnapped up id'the New York City area, and requirements forprotecting t~levision broadcast reception have proved to imposefairly substantial restrictions on the land mobile sharing.

NCTA Propose~ Uniform CATV Technical Standards

The National Cable Television Association (NCTA) has filed apetition with the Commission asking the Commission in effectto be preempt technical regulation of cable television systems.Many municipal cable franchises impose technical standards onthe systems which go beyond the requirements of the presentFCC CATV Tech~ical Standards, and in some instances are inconflict with FCC requirements.

Waiver of TV ~emote Control Requirements Authorized

The Commissiop has authorized the Nebraska Educational TelevisionCommission tofoperate certain of its television transmitters byremote control without the insertion of the required VIT signalat the remote~control point. Three of the stations cannot meetthe requiremepts for the VIT signal insertion and in the case ofthese three stations, the Commission has waved the requirementto permit remote control operation.

4'


Deletion of TY Booste.FsProposed by Commission

In the early days of TV, large numbers of unlicensed "booster"stations sprang up in remote and mountainous areas to receive,amplify, and re-transmit signals received from distant TV stations.Isolating the=receiving transmitting antennas was often quite atrick to keep~he feedback below the point of oscillation, andoften the twoysides of a mountain were used to accomplish justthat purpose. ·

By the time t~e Commission finally got around to authorizingboosters and tjranslators,the vogue for straight "boosters"was waning, wlth frequency translation becoming standard practice.Nevertheless, the Commission adopted Rules permitting the useof on-channel boosters. Only two booster stations·were everauthorized, neither was ever licensed, and there have been nonew applicatio'nsfiled within the last 12 years. Consequently,the Commission is proposing to discontinue any provision for thisservice.



•BUSY BEAUTY SPOT

FOR SPARTAThe sunny, oak-clad Vaca Hills

surround this transmitter site,but there's nothing else sleepyabout this bustling area betweenSan Francisco and Sacramento.Within view of the Sparta 602AFM Transmitter lies Travis AFB,where our returning VietnamPOWs first touched their nativesoil. The Sierra Nevada bringsheavy San Francisco Bay Areatraffic to I-80, below, both summer and winter. This area isgrowing, and builder Don Reeves(left) is planning for the future.

Don has been associated withconstruction of ten stations inhis nearly 30 years in radio, andwas given the huge Broadcast Coordinator's job for the 1960Winter Olympics. Consulting Engineer Cecil Lynch has workedwith Don on many of thoseprojects, mcluding the mammoth·Squaw Valley one.

Yes, these men knowradio, and its future inbusy Northern California.After five years exper-

July, 1973 For More Details Circle (7) on Reply Card

ience with Sparta equipment atKPOP-KPI P in Roseville, Donand Cecil picked Sparta again forthis new venture ... completeShowcase studio outfitting andthe 602A Transmitter with theall new 680 Exciter and 682Stereo Generator.

To their listeners they'reKU IC. To us they're Don andCecil.

SPARTA, the 'just right' company. Small enough to be firstname friends ... big enough tooffer EVERYTHING. Call us.Collect.

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~tfl~&,

- PROUCIyour broa~cast e~uipmentagainst lightning surges

with WllKINSONACUNISURGIPROHCIOHS~

Excessive voltage surges caused by lightning, transformer arcing and induced transients are everyday occurances that cause heavydamage to valuable broadcast equipment.

Now through the use of WILKINSON.voltagesensitive Line Surge Protectors you can protect your equipment from line surges that mayexceed even twenty times the normal linevoltage.

A WILKINSON pulse compensated Line SurgeVarister, is placed across a line of its ratedvoltage. Should a surge or increase of voltageoccur, the resistance of the varister decreasesat log scale as the voltage increases, thus acting as a momentary load or short circuit to thesurge. WILKINSON Line Surge Protectors drawlittle or no current and are capacitor compensated for microsecond surges, thus dampingall line disturbances as well as excessive voltage increase.

A small investment in WILKlriSON Line SurgeProtectors is your assurance that your valuable broadcast equipment will not be damageddue to line surges,

Model SIA-1 11O V. Single phase $17 5.00Model SIA·2 220 V. Single phase $275.00

Model SIA-3 220 V. Three phase $375.00Model SIA-4 440 V. Three phase $475.00

For complete details write to:

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• TELEPHONE (215) 874-5236 874·5237

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lETTERS mm 1~1~m

Las Vegas StationSends Call For Help

Dear Editor:I have had some experience in

soliciting donations of equipmentfor several 10-Watt FM stations.The most fruitful method I cameacross was to make phone calls tothe CE's of stations in the area(including TV). Most CE's I talkedto were very friendly and anxious tohelp locate the equipment weneeded. The only items I found verydifficult to locate were any kind oftransmitter over l O Watts, anantenna system, and monitors thatwork!

I'm currently in the process oftrying to equip a non-commercialEducational FM station to serveLas Vegas, Nevada; the first one inNevada (except two 10-Watters).We still need everything butespecially a transmitter (at least1K), antenna, and monitors. Donations are tax deductible, but ifnecessary, we can't pass up a goodbuy. All help and advice will reallybe appreciated. Also, if you arewith a non-com station, write to usand anything we don't really need,we'll pass on.

Bill Motley, Tech. Dir.Nevada State Public

Radio Assoc.P.O. Box 1425

Alhambra, Cal. 91802

Decision-MakingPerspectives

Creativity in electronics hassparked a veritable revolution inbroadcast technology. The past several years have witnessed a level ofproduct innovation that has touched just about every aspect of thebroadcast/communications industry. Never before have professionalsin this field-even those with wellrounded technical expertise-been

so hard pressed to keep current onnew developments and their impactupon the operations of individualAM, FM, TV, CCTV, CATV, andrecording facilities.True to its mission as the indus

try's technical journal, BroadcastEngineering has endeavored to report and interpret these changes.To accomplish that objective werely upon a cadre of specialists whomonitor for our readers the changing technologies that now and inthe future will influence broadcasters in the selection, operation,installation and maintenance ofequipment, components and accessories. The objective of the contributing editors and the full-time staffis to demonstrate precisely howsignal quality can be attained andmaintained.The readers of Broadcast Engi

neering comprise the buying teamof the broadcast facility. Some exercise full authority in specifyingwhile others exert direct influenceupon the buying and specifyingprocess by which stations and systems are modified or constructed.Some of these readers operate in

\\ OU12..~A..,...te.. Soot.JD S._jS'rtn") IS1"1Í II\u:f>.k1..,•. T¡¡15 !!; A ~¡,) SF'FAt1>J6 .....

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technical capacities. Others holdcorporate or management responsibilities. AU, however, share the obligation to generate a quality signaland to employ techniques andequipment by which this goal isimplemented. But all must have aneye to efficiency and eventual profitability of the overall broadcastoperation. To this extent everyreader shares a management responsibility. Since the new andemerging technologies affect thewhole spectrum of operating economy, Management Highlights areunderscored for most feature articles published.

The Editor

EmergencyWarning Systems

Dear Editor:We are Americans living and

working in Japan and we are verymuch concerned, in our respectivejobs, with news of new productsand technologies. We are quite interested in the February, Octoberand November 1972 articles onautomatic home warning in Broadcast Engineering magazine. In addition, we believe the matter to besocially very significant. Livingoutside America has given us aspecial insight.

America's proposed systemsmust be the first ever developed inany country for home warning.Your magazine has carried the firstauthoritative information we haveever seen anywhere on this life ordeath subject.

As citizens we believe the U.S.Government must be prudent notto make a wrong decision aboutsuch a vital matter. We agree withthe author, Stephen A. Russell,that the general public must get

(Continued on page 10)

1~Plp0~l!~6Q!91S

-:0,º . 1 Shipped from Inventory

I/ Mfrs. of Amerline reels

I " POLYLINE ¡31214a9.11s1· CORP. 2449N.Western, Chgo. 60647


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The Belar TVM-1 Modulation Monitor isthe most accurate monitor available.Our advanceddesign starts where othersleave off. TVM-1 Monitors both positiveand negative modulation simultaneouslyand registers the higher of the two. Yes,it even tells you whether the modulationis positive or negative and calibrationaccuracy can be checked from the frontpanel modulation calibrator at any time.

and aural carrier independently or auralintercarrier. Thesemonitors provide continuous monitoring with inhibited offfrequency alarm drivers, switch settableto either ±500 or 1000 Hertz. It requiresthree successive errors to produce analarm. This means no false alarms foryou.

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AELtransmitterfeatures:

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To get it, we combined two AEL FM-25KD25KW FM transmitters, whose combined outputsare connected to the antenna through a true 90°hybrid combiner.

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LETTERS U® uoot ~~mrmm(Continued from page 9)

their home warning from the commercial broadcasters (EBS) fromthe standpoint of national security,the public's economy and technicalfeasibility.

When we saw your story inTokyo we were attracted by thefact that the technology for theproposed Unified Public AlertingSystem was invented by a Japaneseengineer. It was very beautiful forus that a Japanese had gone to thetrouble of offering Americans ameans for saving lives during anuclear attack, when his very owncountrymen were twice victims ofa U .S. nuclear attack. We hope hisdiligence will not go unappreciated.The limited ABM, home warning,and civil defense, are now the onlypurely defensive protection we canrely on.There is too much emphasis on

purely offensive means and weapons, for both defense and deterrence. A convincing, purely defensive deterrent, such as a perfect,low cost warning system for everyhome, is needed. In that sense,U .S. cities and people are nowvulnerable to any sudden attack,just like defenseless hostages.

Edwin C. MernerStephen J. Baxter

Kanagawa-ken, Japan

SEND YOURUTTERS TO THE EDITOR

toBroadcast Engineering

1O14 WyandotteKansas City, Mo. 64105




Radio,

manager. KI I I. Corpus Christi,Tex., and William F. Turner,executive vice president and generalmanager, KCAU, Sioux City, Iowa.Turner continues as chairman.

TV Committees NamedFour radio broadcasting execu

tives have been named to. two-yearterms on the Small Market RadioCommittee of the National Association of Broadcasters.The appointments were made by

NAB Joint Board ChairmanRichard W. Chapin, president,Stuart Broadcasting Co., Lincoln,Neb., and NAB President VincentT. Wasilewski.

Named to the seven-man Committee were Edward D. Allen, Jr.,president and general manager,WDOR, Sturgeon Bay, Wis.;George Allen, president and generalmanager, KLGA, Algona, Iowa;Jim Ballas, general manager,KOWB, Laramie, Wyo., and PaulReid, president and general manager, WBHB, Fitzgerald, Ga.

Continuing members are ArchHarrison, Jr., president and generalmanager, WJMA, Orange, Va.; AIRock, general manager, WSMN,Nashua, N.H., and William J.Ryan, general manager, WNOG,Naples, Fla.

Rock was named chairman.Secondary MarketTV Committee

Three television broadcastingexecutives have been named to twoyear terms on the Secondary Markets Television Committee of theNational Association of Broadcasters.The appointments were made by

NAB Joint Board ChairmanRichard W. Chapin, president,Stuart Broadcasting Co., Lincoln,Neb., and NAB President VincentT. Wasilewski.

Named to the seven-man Committee were William F. Duhamel,executive vice president, KOTA,Rapid City, S.D.; Robert E.Krueger, president and generalmanager, KTVB, Boise, Idaho, andJohn Shott, general manager,WHIS, Bluefield, W.Va.Continuing members are Frank

Harden, president, WCBD, Charleston, S.C.; Ray Johnson, executive

July, 1973

Business Trends

vice president and general manager,KMED, Medford, Ore.; Michael D.McKinnon, president and general

A number of broadcast equipment manufacturers managed andsold their way into the black lastyear. There's no denying thatbusiness is good and growing. If the

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Writeor call Pentagondirect for full informationon thePRO-Series2800line of 8-lrack duplicating systems.You'll begladyoudid.

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íl~OOOO~IWNEWSSMPTE Gearing Up For Oct.(Continued from page 11)

business at the NAB convention isany indication. the broadcasters arein much better shape. And thatmeans the manufacturers will havea fast. busy year.

As an indication of how muchimprovement was possible, TeleProIndustries reported that 1971 salesand earnings of $4.6 million rose tojust over $7.3 million for 1972.TclcPro is the manufacturer ofFidclipac tape cartridges.According to Dennis W.

Boardman. president of TelePro,sales and earnings for the yearended December 31, 1972 reachedtheir highest level since thecompany \\'<IS formed in 1963.TclcPro is a 58.1 per cent owned

subsidiary of El-Tronics, Inc.

arrangements chairman, will beresponsible for all the non-programactivities and arrangements. He willappoint a comprehensive committeeto assist him in providing the manyservices required at an SMPTEConference.

The program chairman, arrangements chairman, and the exhibitchairman, have been appointed forSMPTE's 114th Technical Conference, by SMPTE editorial vicepresident Gerald G. Graham, andconference vice-president HarryTeitelbaum.

The Conference is scheduled forNew York's Americana Hotel,October 14-19.R. L. Pointer, director, broadcast

engineering, American Broadcasting Co., appointed programchairman, will have the basicresponsibility of putting together afive-day technical papers program.He will appoint a program committee made up of topic chairmen,each representing a different discipline within the motion picture andTV areas. Topic chairmen willparticipate strongly in the acquisition of papers.

Charles Ahto, MPO/Tape Films,

Free Alignment BookletFidelipac, a division of TelePro

Industries Incorporated, announcespublication of their booklet, Aligning Your Cartridge System, A Practical Approach. This 12-page booklet discusses machine alignment;head height, azimuth and insertionadjustments; tape guide and pinchroller adjustment; cartridge positioning and other subjects necessaryfor automatic tape cartridge recorder/reproducer maintenance. It isavailable, free of charge, fromFidelipac, 3 Olney Avenue, CherryHill, New Jersey 08034 or fromFidelipac distributors.

For Latest NewsSee

Direct Current page 4

iNcreAseFmttsrercerswituoutCHaNGiNGrormxt

Reach into those difficult areas, car and features variable horizontal-to-receivers and small portables. These vertical gain ratios.hard-to-reach groups can represent a Your stereo performance will also im-large audience. With our FM "Pene- prove, because of the "Penetrator's"tratar" antenna, you no longer give exclusive .field trimming. They allowthis audience to your competitors. you to a~¡ust your VSWRvalues, after

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JAM PRO ANTENNA COMPANYA DIVISION OF COMPUTEREQUIPMENT CORPORATION

Phone (916) 383-1177 • 6939 Power Inn Road, Sacramento, California 95828

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NAEB Sees IncreasesIn Hours And Services

What are the program plans, theoperational costs, and the over-allneeds of public television stations inthe years to come? A study conducted by NAEB's television division, Educational TelevisionStations, asked those questions ofstations across the country-with aparticular focus on the year 1976.Here are some of the projectedanswers:•A full-service operation of 48

weeks per year, seven days perweek, 16 hours per day (contrastedto 40 weeks, six days and 13 hoursin 1972);•A program source mix of local

production, 2(1 1/2 hours/week;tape/film, SO hours/week; and"real time" interconnection, 49hours/week;

•Local production needs of classroom instruction, 8.7 hours/week;public affairs, 4.2 hours/week; nonclassroom instruction, 3.5 hours/week; cultural, 3.0 hours/week;newscasts, 1.4 hours/week; andother, 1.3 hours/week.•Local production costs of

remote coverage-current events,$3, 700/hour; 32-program schoolcourse, $1,800/program; socialissue documentary, $12,000/program; and in studio-publicaccess, $1,000/hour.Licensees responding to the ETS

questionnaire (62, representing 113transmitters) indicated that an"optimal funding mix" for theirregular production and broadcastoperations would be: Federal, 32.Spercent; state/local. 44.0 percent,

Commissioner Wiley in the ·field

FCC's Dick Wiley tours WTIM, Springfield, Ill. during trip to Illinois Broadcasters Association meeting. Wiley (at left) is shown here with President DonJones and CE Roy Fritcher.

July, 1973

and private, 25.S percent.Questionnaire responses pointed

to a fiscal year 1976 program mixof approximately 20 percent localproduction, 40 percent tape andfilm use, and 40 percent from realtime interconnection.

Different kinds of licensees willemphasize different kinds of programming:•University stations will place

heavy emphasis on public affairsand cultural, locally produced programming.•State stations will focus on

classroom and non-classroominstruction.•School system stations will place

their emphasis on child-directedinstructional programming.

•Community stations will seek aprogramming mix with broaderaudience appeal.The study also shows that

stations related to academic institutions are Jess likely to provide yearround, seven-days-per-week, fullservice operation, either currentlyor in their projections for thefuture.

"Ironically," the report suggests,"the diversity of public television,which is truly a boon to its manypublics, is an impediment to its fulldevelopment. It is an impedimentbecause diverse purposes are oftenperceived as competitive purposes.This perception often results in themanagement of information forspecific activities and createssporadic areas of growth, ratherthan integrated, planned overalldevelopment."

Data from the ETS questionnairewas analyzed and interpreted by theOhio University Broadcast ResearchCenter, under the direction ofOUBRC director James A.Anderson. Copies of "Operationsand Costs: A Study of EducationalPublic Television Stations" may beobtained from NAEB/ETS.

Want A FreeSubscription?

Send Requests ToBroadcHt Engineering1014 Wyandotte StreetKansai City, Mo. 64105

13



New SBE Chapters FormingThe following areas represent

locations for possible future chapters. Informa tion on any plannedorganizational or technical meetingsmay be obtained from the individual listed as the "contact" in eachcase. Anyone interested in chapteractivities in other locations maycontact Virginia Doss, AssistantSecretary-Treasurer, SBE, P.O. Box88123, Indianapolis, Ind. 46208, orat WRTV, 1330 N. Meridian,Indianapolis.

In some cases, assistance fromSBE national officers and directorsmay be available. Contact anyofficer or director, or SBE President James C. Wulliman, atWTMJ, 720 East Capitol Drive,Milwaukee, Wisc. Those involved inthe development of new chaptersshould also keep the SBE JournalEditor posted so that this work canbe aided by promotion in theJournal.

ContactH. J. Bart Paint, telephone 882-6644,or Chuck Deen, KOOL TV, 511 WestAdams, Phoenix, Ariz., telephone 271-2345.John Blattner, 11001 N. Kendall Dr.,Apt. Al07, Miami 33156.Arthur H. Rounds, 1321 Aspen Drive,Florissant, Mo. 63031.Bob Beurket, Asst. Chief Engineer,WRIK TV, Ponce/San Juan, PuertoRico. Telephone 809-724-7575.Robert Daines, CBS Laboratories, OneEmbarcadero Center, San Francisco,Calif. 94111.

LocationTucson. Ariz.:

Miami. Fla.:

St. Louis, Mo.:

Puerto Rico:

San Francisco,Calif.:

SBE Insurance Plan BoomsThe new SBE Directory is ex

pected to be out in two to threemonths, perhaps by the time thenext issue of our Journal reachesyou....The rate of increase in SBEmembership has increased sinceBroadcast Engineering started toinclude the SBE Journal as asupplement ....The SBE insuranceprogram is turning out to be even agreater bargain than at first expected. A 25 percent dividend wasreturned to members the first year,and a 40 percent dividend thesecond year.

14

Another new chapter within thenext few weeks may be Louisville,KY.... Former SBE President andoutgoing Director Lew Wetzel urgesmembers to apply for Senior Member grade as soon as qualified.Advanced in grade conceivably maybe a step toward promotion in yourjob. To upgrade your SBE membership, merely fill out an applicationblank (there is probably an application printed in this issue of BE),and check off the appropriatenotation (x) Change in Grade, or (x)To Sr. Member.

SBE MembersOn The Move

Klaus Binder has accepted theposition of Director of Engineering,United Broadcasting, Washington,D.C. Klaus is a former chapterchairman.

Michael D' Amore has been promoted by TeleMation to DistrictManager for the Kansas City office.

Ralph Thompson, former director of engineering WGBI AM FMand WDAU TV, Scranton, Pa., hasmoved to Las Vegas, Nevada, wherehe is Staff Engineering Consultantfor Donrey Broadcasting, P.O. Box2927, Las Vegas, 89104. Ralph hadbeen active as chairman and inother positions in Chapter 2, Northeastern Pennsylvania.

By the middle of July, SBE members will have received a copy bymail of the new SBE Directorylisting members alphabetically andgeographically, regional chaptersand chairmen, and society objectives. Also included is a list ofofficers, directors, and honoraryand fellow members up to November, 1972.

Paul Evanosky, WVIA FM TV,and chairman of chapter 2, recentlyreturned from the Bahamas wherehe and his new bride were honeymooning.Charles Hallinan, former chief

engineer of WKOP-AM-FM, Binghamton, N. Y., and former president and executive director of theSBE, is now a field sales engineerwith CCA Electronics and has beenguest speaker at meetings of severalchapters in the northeastern U. S.Hallinan also brings along CCA'slatest gear.

Society NotesFrom The Editor

Through these pages, provided byspecial arrangement with the publisher of Broadcast Engineeringmagazine, members of the Societyof Broadcast Engineers may nowcommunicate with each other; SBEheadquarters can pass along information to the general membership;SBE chapters can report and an-




nounce information concerningtheir meetings or other activities;and we can air issues of vital concern to all of us who are employedone way or another in the field ofbroadcast engineering.

A means of communication isvital to any organization. Let's utilize this unusual opportunity whichis now available.

Here are some reminders fromSBE Headquarters: Chapters: Besure to apply for annual rebatesfrom SBE headquarters. A rebateof up to $100 annually is possiblebased on membership attendancefor the preceding year. To obtainthis rebate it is necessary to complete the Annual Attendance Report Form which may be obtainedfrom Virginia Doss, SBE, P.O. Box88123, Indianapolis, Ind. 46208.Virginia would also like chapters toremind members that attractiveSBE tie tacks are available fromher for $3.50 (members only).

When corresponding with SBEabout your membership includeyour membership number. Submitchange of address promptly. If youare not receiving Broadcast Engineering magazine, provided as acourtesy by the publisher to SBEmembers at no cost, notify VirginiaDoss. Letters to the Editor, ChapterNews, articles, and other information for publication should be sentto SBE editor, Joe Risse, P.O. Box131, Dunmore, Pa. 18512. Articlesneed not be professionally writtenbut they should be technical informa ti ve-diagrams can be handdrawn, but legible and accurate.

Chapter NewsChapter 1 - Binghamton, N. Y.Chairman: Larry Taylor,WENY AM FMMark Twain Hotel,Elmira, N. Y. 14902The annual joint meeting hosted

by chapter 1 was held on May 8that the Owego Treadway Inn,Owego, N.Y. The advance preparation and promotion efforts ofchairman Larry Taylor and hisassociates paid off in good attendance by members of his chapter aswell as by members of chapter 2and 22. A smorgasbord dinner pre-

July, 1973

ceded the technical and businesssessions. Angelo Domino, field salesengineer for Tektronix, provided anequipment exhibit, and a áº-minutedescription of their á iiá VIT Insecter and the áííñ AutomaticVideo Corrector. Bob Mahoney provided equipment demonstrationsbefore and after the meeting.The feature of the joint meetingwas guest speaker Otis Hanson,chief of existing facilities of theFederal Communications Comrnis-

sion, Washington, D.C. Hanson isone of those involved with thedrafting of new broadcast regulations, and confined his talk mainlyto that topic. A high degree ofinterest was evidenced from thelengthy question-and-answer sessionthat followed. Audience appreciation was also evident from thesustained applause.


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Chapter 2 - Northeastern Pa.Chairman: Paul Evanosky,WVIA AM FMOld Boston Rd., Jenkins Twp.Avoca, Pa. 18640

The regular monthly meeting ofchapter 2 was a joint meeting heldwith chapters 1 and 22, as described in the preceding report. Thechapter's annual Ladies Night wasalso held on May 8th at IremTemple Country Club, Dallas, Pa.;a refreshment hour and dinner werefollowed by dancing until earlymorning hours. Corsages were provided for the ladies plus specialfavors donated by Shelborne Electronics of Wilkes Barre and PursellElectronics of Scranton. The eventwas planned by Milan Krupa ofWPTS and Paul Evanosky, Jr., ofWBRE TV. Krupa also served capably as Master of Ceremonies.

Chapter 15 - New York, N. Y.Chairman: John M. Lyons,WWRL AM41-30 58th St., Woodside, N.Y.

The May 10th meeting featured adual program as has become theusual practice for the New YorkChapter. One program is plannedto appear to radio engineers andthe other to television engineers.Held at the WQXR PresentationTheater, 2 blocks from the PortAuthority bus terminal, at 229West 43rd St., between 7th and 8thAvenues, many availed themselvesof the opportunity to join in asocial hour and dinner in the NewYork Times Cafeteria, 11th Floor ofthe Times Bldg. The program designed for audio people was"Stereo-Mono Compatibility inBroadcast Audio Equipment" withEric Small, a broadcast audio consultant and chairman of the Broadcast Papers Committee of theAudio Engineering Society, theguest speaker. Small discussed theproblems of left/right mixing forthe composite mono signal as itapplies to audio as well as to FMstereo equipment. The TV programwas "Time Base Correction fromVideo Tape to Quad". Alan Nichols

16

of the Harvey Group was the guestspeaker. He reviewed and demonstrated time base correction neededfor transference from Y2" videotapeto quadruplex, with the emphasison how to use low-cost videotapeequipment in this process. Thoseinterested in attending N. Y. chapter meetings may contact BobWoerner, secretary, at 212-535-1000or Art Silver, Gates Radio, 212-889-0790.

Chapter 16 - Seattle, Wash.Chairman: John Maxson,KETO FM17425 63rd Place. S.E.,Issaquah, Wash. 98027The May 9th meeting, held at the

Norseland Restaurant, Seattle, atnoon, featured Howard Haskett,vice president, sales, and ElmerWilson, technical lead man, both ofMann-Russel Electronics, Tacoma,who spoke on "Novem Applicationsof RF Energy". The topic wasrelated to the use of dielectricheating in the manufacture of woodproducts ranging from laminatedbeams to tennis rackets and moisture detectors.

Bob Dietsch, of the local FCCoffice, provided his monthly reporton Commission activities.

Annual election results, held alsoat this meeting are as follows:Chairman: John Maxson, KETOFM, Issaquah, Wash.; Vice Chairman: G. Lewis Rambo, KCTSChannel 9, Seattle, Wash.; Secretary/Treasurer: Bill Pickering,KOMO AM TV, Seattle, Wash.;Editor, NEWSLETTER: NickFoster, 1124 N.E. 147th St., Seattle,Wash.

Chapter 18 - Philadelphia, Pa.Chairman: Jack Jones,Asst. Dir., Engrg.,WCAU TV,City and Monument Aves.,Philadelphia, Pa. 19131On May 22, social hour and

dinner preceded a talk by guestspeaker Richard Smith, engineer incharge, Federal CommunicationsCommission, Philadelphia. Smith'stalk on the activities of the FieldEngineering Offices, was supportedby slides. A spirited question-andanswer session followed. There wasa good turnout of members andguests.

Chapter 20 - Pittsburgh, Pa.Chairman: Henry R. Kaiser,.wwsw,1 Allegheny Square,Pittsburgh, Pa. 15212

On May 17th, a noon luncheonat Buddies Restaurant was followedby an open discussion concernedmainly with "Antenna Monitors inDirectional Antenna Systems."Members were provided an advancecopy of FCC Docket No. 19622,which is an FCC Inquiry on thistopic, so were well prepared tocontribute opinions.

Chapter 22 - Central New YorkChairman: Hugh Cleland,WCNY TV FM506 Old Liverpool Rd.,Liverpool, N. Y. 13088

The May 8th meeting was heldjointly with chapter 1 of Binghamton and chapter 2 of ScrantonWilkes Barre, and featured a talkby Otis Hanson, chief of existingfacilities, FCC., as is described inthe chapter 1 meeting report. Thenext meeting, scheduled for June21st, was to be an inspection ofWSYR's new on-air and productionswitching system.

Chapter 28 - Milwaukee, Wisc.Chairman: Ed Wille,KENCOM7835 W. Caldwell St.,Milwaukee, Wisc. 53218The May 21st meeting, held at

WTMJ, Inc., Radio City Auditorium, featured guests Jan Pritz! ofWMVS, Ray Hernday of WTMJTV, and Todd Boettcher of WTMJ.The meeting included tours of thevery fine color mobile units ofWTMJ TV and WMVS. Among theequipment observed and discussedwere TR-60 and TR-4 video taperecorders, and Norelco PC-70 andRCA TK-44 color cameras.Ed Wille, chairman, appointed

an Election Committee consisting ofGuy Morrison, John Lafferty, andJim Wulliman, who were to comeup with a suggested slate of nominees. The committee recommendedthat the present officers be retainedfor another year, but that nominations should also be accepted fromthe floor. Results of the electionwill be reported in the next SBEJournal section of Broadcast Engineering.




TranslatorConventionHeld In Utah

The 1972 national meeting of theNational Translator Association washeld recently in Utah. Although itdrew well, it might even have beenhigher if it had been held in a morehighly populated area ....but then,Utah is a good example of wheretranslators are so often needed.

Bruno Zucconi, of Scala RadioCorporation, presented a paper onthe Modern Antenna. He pointedout that good transmitting antennasare now available, as well as goodtransmission lines, but the realproblem, he stated, lies in the homeTV antennas. This is the weak linkin the TY-to-translator-to-homeservice.

Bill Loveless, Assistant Directorof Engineering, summarized theexperience Bonneville InternationalCompany had had in applying forsome 20 FM translators. He statedthe need to select sites that were

outside other FM stations l.OMY/M plus watching ± three channels and the need for new per·mission from the Forestry Bureau.

Marshall Smith of Aerodyne presented a paper on the basic featuresof the new "Modern Translators".Most new translators, both TV andFM are of the solid state variety,especially in VHF. Some UHFemploy one or two tubes. Onelesson the operators have learned isthat, unlike tubes, transistors arenot very forgiving. In this respectsolid state is a new ball game.

Ed Craney, talked on the"necessity of making translatorsself sustaining". In addition torelating the beginnings of the NTA,he humorously referred to some ofthe early illegal translators. Thereal reason there has not been ahealthy growth of translators is dueto the need for a profit motive. Thefact that KSL showed their translator film to the FCC has been onefactor in getting the FCC to increase the length of local announcements from 20 to 30 seconds. Hefurther pointed out a weakness ofthe FCC Rules in restricting FM

translators to just the 20 Class "A"channels. The Rules should bechanged to permit all channels tobe available. For example, inJapan, a country the size ofMontana, there are 3000 translators. Yet in the United States wehave the same number in the wholecountry. In fact, by proper use ofspectrum, Ed Craney states wecould accommodate 100,000 translators.

In the afternoon there were talksby industry and consultingengineers. Nat Ostroff of Aerodyneread a paper on the latest conceptof envelope delay in TV translators.Robert A. Jones, consultingengineer from La Grange, Illinois,talked about FM translators. Thistalk included a slide presentationoutlining the FCC Rules as well asshowing examples of some of hisclients' FM installations, and theunique features of the Model J-316/J-317 translators made by theVersa-Count Company. G. Johnsonof ECW, lnc., spoke about the needfor translator operators to resist thefurther encroachment into the TVbands.

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was large enough to be subjectivelydiscernable. Such highly specializedcolor cameras built for NASA withseemingly limitless public funds donot present immediately practicalsolutions for terrestrial color television problems. The more commonsingle tube color camera operateson a much different sequentialprinciple.

The faceplate of the pickup tubeinvariably a vidicon at this time-hasin front of it a series of vertical (ordiagonal) color strips (Figure 2)which are applied by electro deposition in a vacuum chamber. Thesefinely spaced alternate color stripswhich act as filters in the selectedprimary colors break up the imagefocussed on the camera tube faceplate by the optical system. Thealternate color filter strips are ofcarefully selected widths and atprecisely calculated spacings. Thispermits the image scanning actionof the pickup tube electron beam togenerate video signals which havediscrete center frequencies for theprimary color components. Bandpass filters centered at these discrete frequencies are then used toseparate out the RGB informationin the video output signal of thepickup tube preamplifiers. The synthesized primary color (RGB)signals so obtained can then beused to drive the matrix circuitry ofan encoder and produce a fullycompatible composite output signalin the television standard desired.

A great deal of developmenteffort has gone into improving theresults that can be obtained withstriped filter single tube cameras.However, they suffer from certaininherent defects that make themrelatively unsuitable for any exacting color television applications.Among the disadvantages in resolution where there is fall-off towardthe corners, interference patternsdue to the color filter structure with"picket fencing" effect under rapidmovement conditions and low sensitivity (requiring a high ambientlight level) due to the losses in theoptical path. Also a problem, areareas of color desaturation in thepicture associated with scanningbeam velocity errors arising fromslight non-linearities of the horizontal sweep waveform. Registrationproblems are exchanged for sweeplinearity problems.

For applications where adequatelighting is easily available, the subject matter requires little depth offield and no great resolution isrequired, (scanning color captioncards, fixed closeup of an announcer, etc.) the better versions ofthis type of camera may very wellserve the non-broadcast purpose ata modest outlay in capital equipment cost.

The Two Tube CameraThere are several versions of two

tube cameras all of which takeadvantage of a unique character-

LENS

DICHROLICBEAM

SPLITTER

IMAGE

TUBES CAN BEVIDICONS OR PLUMICONS

OR COMBINATION

TWO TUBE CAMERASIOE BY SIDE MINIFIELDIMAGES IN REO/BLUECHANNEL

GREEN AND LUMINANCE

RED PICKUP

BLUE PICKUP

20

Figure 4

istic of human vision. Visual acuityis greatest in the green region andfalls off in the red and blue areas.Since the luminance matrix of acolor television signal is 59 percentgreen (and this contributes greatlyto the resolution of the overallimage), the two tube camera assignsone tube to handle the "wideband"green channel and uses the secondpick-up tube to take care of the redand blue signals either sequentiallyor simultaneously.

An optical splitter behind thetaking lens produces separateimages that impinge on the pickuptubes as follows: The direct path tothe "green" tube which alsodoubles as the luminance channel isthe high resolution image whichcarries the bulk of the video information. The secondary image produced by the splitter is focussed ona pick-up tube with a color stripfilter with only cyan (negative red)and yellow (negative blue) elements.

By the process described for theone tube camera, but now appliedonly to the narrower band widthrequirements of the limited acuitychannels, a red and blue videosignal (by inverting cyan andyellow) is derived from this secondpick-up tube. After preamplification of both camera tube outputsand appropriate extraction throughband filtering of the red and bluevideo signals, the RB and Y signalscan be matrixed and encoded into acomposite color signal.

Another approach in the twotube camera is to further split theimage in the red/blue channel intotwo side by side or one over theother images that appear on theface plate of the pick up tube.While the images are smaller, thelimited resolution requirements forred and blue make it possible toproduce adequate results by thismethod.

Still another technique that wasused on portable color camerasdeveloped for ABC sports coverageused a small synchronous colorfilter wheel with alternate red/blueoptical filters in the red/bluechannel. While the two-tubecamera out-performs the singletube version in size and weight, it

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does so at a cost and complexitythat sometimes exceeds the threetube version while still exhibitingsome of the restrictions of the onetuber. Where cost, size and weightare imperative factors and somecolor picture degradation is acceptable, the two tube camera canfill the bill.

The Three-andFour-Tube Cameras

Almost all color televisioncameras over the ten thousanddollar price bracket that are beingproduced today are of the threetube variety. There are, however,enough four-tube cameras stillaround to be worthy of mention.

Early high quality studio colorcameras using three image orthicons were rather heavy and monstrous devices. Since most of theresolution information is conveyedin the luminance channel, cameradesigners were quick to come upwith the approach that a colorcamera could be built with a highresolution luminance path with alarge orthicon pick up tube andthree low resolution color channelsusing vidicons to supply RGBsignals that could be matrixed withthe Y output of the orthicon. Thesewere called separate luminancecameras and were widely used asstudio and telecine cameras. Because four-tube cameras were relatively immune to the effects ofregistration drift, they were produced widely in two configurations,an I.O. with three vidicons or fourplurnbicons.The switch to three tubes was

occasioned by two significantdevelopments, stable solid stateelectronics and a new family ofmore sensitive pick up tubes including the plumbicon, the SECtube and the silicon diode. It wasnow possible to design new colorcameras using only three tubes withcharacteristics equal to or betterthan the previous four tube type.

The three-tube camera is astraight forward approach to theoptical separation of the RGB elements in the image by prismsand/or dichroic mirrors. The red,green and blue optical paths pro-

22

3 TUBE CAMERA - RGB

OICHROICFILTERS

ANDMIRRORS

IMAGE

TUBES CAN BE: DRTHICDNSVIOICONSPLUMBICDNSSI LICON DIODESS.EC.DR COMBINATIONS

PICKUP TUBESRED

PRE-AMPRED TUBE

GREENPRE-AMPGREEN TUBE

BLUEPRE-AMP

BLUE TUBE

Figure 5

duce a focussed image on the flaceplate of the appropriate pick uptubes, each of which produces avideo signal relative to its selectedprimary color. The output signalsfrom the camera are RGB noncomposite video at a nominal 75Ohm impedance and are deliveredto the camera control unit formonitoring, further processing andencoding into a composite colorsignal output.

Three-tube color cameras arewell suited for most studio applications since they provide a goodbase from which a proper composite signal can be generated.These cameras also lend themselveseasily to external image enhancement, better signal monitoring andmanipulation and full broadcastquality encoding techniques.Three-tube cameras do vary

greatly in price, performance andperipherals and the selection of abasic camera and its options mustbe tied to budgetary allowances inrelation to the desired results. Hereare some of the factors that shouldbe considered in selecting a threetube color camera.

Optical SystemsThe first element which controls

the quality of the picture appearingat the photosensitive surface of thepick-up tubes is the combination oftaking lens, relay lenses, and

dichroic filters or beam splittingprisms that combine to form theoptical path of the color camera.

While the manufacturer of thecamera usually provides no optionto the internal optical system of agiven camera model, most of themdo offer a variety of lenses whichcan be specified by the user. Lenseshave become sufficiently standardized that the major lens manufacturers have interchangeablemodels covering a wide range ofapplications. Lenses also come invery different price brackets whichusually relate directly to the maximum aperture, the ratio of variablefocal lengths and the method ofcontrol.

A color camera set up as part ofa telecine chain requires a simplefixed focal length lens with areasonable aperture since it is looking at a projected image withadequate ambient light level and ina constant focal plane. Some filmcameras dispense entirely with afocussing lens and use a simplesingle element field lens into whichthe projector image is projected.This results in sharper picturesbecause several optical elements areeliminated.

Most studio cameras are requiredto cope with a variety of conditionsthat encompass extreme changes incamera to subject distances and inthe variability of the light level and






contrast ratios of the scene. Inaddition to this the speed at whichthe change may have to take placeimposes a need for automatic controls that maintain proper lenstracking between the extremities ofthe optical limits of the lens.

It would obviously be the easiestsolution to purchase a lens with themaximum "F" stop, the greatestzoom ratio and the best electricallyoperated control system. Unfortunately, such an approach is impractical from both a budget or anadaptability viewpoint. Top of theline zoom lenses with an 18:1 ratiomay be larger physically than thelow cost camera it would attach to,and certainly more expensive. Smallaperature, low ratio lenses may notsuffice for a particular use. Theselection of the lenses should bemade on the following basis:

l. The maximum aperture shouldbe adequate to provide suf-

ficient image intensity at thepickup tubes under the minimum ambient light level thestudio is expected to operate at.

2. The lens should have a zoomratio that accommodates thescale of minimum to maximumimage distances for the type ofprogram production envisaged.Any unique requirements canusually be met with lens extenders that are added whennecessary. Some lenses havebuilt-in snap-in extenders.

3. The lens should exhibit goodfocal tracking between its minimum and maximum zoompositions. This feature cannotbe over emphasized especiallywhere less than the most proficient cameraman is to beused.

4. The quality of the lens shouldbe carefully evaluated forchromatic abberations, shading,flare suppression, image resolution, light transmission and

FOUR TUBE CAMERA

LENSBEAM

SPLITTER

IMAGE LUMINANCE TUBE¡.---

PRISM

t ==I: ::::311.1·-·-t-·-·-·-·-·-• \ BLUE TUBERED TUBE

ONE IMAGE ORTHICONTHREE VIDICONS

GREENTuBE

24

Figure 6

edge focus at wide openings.S. The mechanical side of the lens

is also important, check forsmooth operation of the iris,zoom mechanism and ease ofmounting and demounting. Ifthere are electrical servo controls on the lens make sure themotor drives function freelyand that they reset well fromboth directions.

6. If the lens uses extenders to increase focal range, find out ifthey are bolt-on, screw-in, orbuilt-in. The former take alittle time to attach, the lattercan be inserted in seconds butcost more.

In making a comparison betweendifferent color cameras, particularlywith regard to optimum performance, it is important to make surethat the differences are not generated by the lens rather than theinternal camera optics or electronics. Any valid comparison between two cameras should requirethe same or nearly identical lenses.

Internal OpticsWhile the internal optics do not

generally allow latitude of any different choice to the user, they dorepresent a variability in the qualityof different cameras. The lenses,mirror and/or prisms that form theimaging system should be mountedon a firm base and be protectedfrom the outside environment asmuch as possible.

The relay lenses and mirrorsshould introduce no significant geometric or chromatic distortions.The dichroic mirrors or prismsshould have suitable optical spectrawhich provide precise colorimetricseparation of the primary signals. Arigid optical path will eliminate theneed for frequent mechanical readjustments of the glass elements.Adequate protection from theenvironment will keep out dust,dirt, moisture and other imagedetiorating factors like stickyfingers that leave hard to removeoily deposits. Some cameras havefixed optical elements which require




no adjustment for the life of thecamera.

Last but certainly not least, theinternal optics of a camera sometimes limit the variety and focallength of the applicable availablelenses by requiring unusual backfocal distances from the rear exitpupil. It is important to be surethat the desired camera will matewith the selected lens.

Tube SelectionCamera tubes not only come in a

variety of photo conductive surfaces, diameter sizes and physicallengths, but· also in increments ofquality that determines their price.Much in the manner that solidstate devices are manufactured thengraded according to quality/costcategories, image pickup tubes arealso graded by the manufacturer.The user is given the choice ofpaying a premium price for broadcast quality or a bargain price forindustrial grade tubes with certaindeficiencies. Where optimum colorquality is desired, the three tubesare supplied as a matched set withcarefully selected conjugate colorresponse curves.The most noticeable type of

deficiency is the surface blemishwhich causes a spot in the imagethat cannot be eliminated. Thenumber and position of suchblemishes is the criterion by whichthe tubes are graded upward ordownward. Blemishes are lessnoticeable in the low acuity red andblue channels than in the wideband green channel, making tubejuggling a way of sometimes gettingby with industrial grade units,which often exhibit more lag thanthe top grade tubes. Only the usercan decide if his application demands the matched marvels or thecheapie.

When making a comparison between different color cameras, oneshould ascertain that both are usingsimilar grade tubes from a performance standpoint or are beingquoted with the same tubes withregard to cost.The vidicon, plumbicon and sili

con diode have similar enough

July, 1973

physical and electrical characteristics, that many cameras offer thecustomer the same model withtubes of his choosing. Only the SECand image orthicon tubes are sufficiently different to require specialcamera structures to house them.There are some basic ground

rules to selecting the best tube ortubes for a given utilization, theyare:l. Vidicons may be used where

there is a high ambient lightlevel on the scene to be televised and where the lag produced by image movement isnot objectionable. Telecines,caption scanners, outdoorscenes and brightly lit studiosqualify.

2. Plumicons, which seem to bethe most popular these days,make good pictures in lowerlight levels and exhibit little orno lag characteristics. Plumbicons which cost more than vidicons may be a good investmentif they save you from needingextra lights (in your old monochrome studio) which is usuallyfollowed by additional airconditioning to keep the talentcool.

3. Where extended red sensitivityis required, the plumbicon inthe red channel is replaced by asilicon diode tube. This notonly extends the colorimetricrange but improves the noisecharacteristics in that part ofthe spectrum where it is usuallymost objectionable.

4. SEC tubes are used only wherethe ambient light levels are verylow. While they make goodcolor pictures in just a few footcandles, the inherent noise levelis higher than in any of theother pick up devices exceptimage orthicon. Unfortunately,even when the light level increases the signal to noise ratiodoes not improve significantly.Applications that require SECtubes are usually very specialized and are willing to sacrificeSIN ratio for sensitivity.

S. The image orthicon has beenvirtually displaced by the

plumbicon in new color cameradesign. the I/O has high sensitivity and good resolution withlittle lag, but its large mechanical size, set up complexity, andhigh price have phased it out ofmodern cameras. It also suffersfrom some of the noise problems inherent in the SEC tube.Most of the color cameras builtprior to 1965 used one or moreimage orthicons.

Tube SelectionComplex, expensive, high tech

nology products like image pick-uptubes always confront the individualrecipient with the dilemma ofaccepting what comes out of thesuppliers shipping carton on goodfaith or to go through vigorous incoming inspection procedure that istime consuming and intricate.Large television networks haveroutine methods of detecting substandard tubes and, since they arevolume buyers, they usually end upwith the pick of the litter. Manufacturers being what they are, it isnot unlikely that the network runtis repackaged in a new box andsent out to a less meticulouscustomer.

To avoid being a recipient of"hand me down" tubes a studioshould have some minimal targetsof performance that can be checkedwhen the tubes are installed in thecamera. With the lens cap on, theimage in the view-finder is the stateof the target. Check for blemishesand pin holes, especially as towhere they are in relation to theimage. The same defect may beperfectly acceptable at the edges ofthe image and totally unacceptablein the action areas. Check forshading effects in dark current,then remove the lens cap and setup camera normally to check forshading, colorimetery, noise, lag,halos, etc.

Another alternative is to knowyour supplier. Some camera manufacturers or distributors do theirown screening of pick up tubesbefore shipping them. A conscientious supplier can save you a lotof camera tube problems. D

25



WHO? ....ME?

Let's get going on thatcommunity survey

By Pat FinneganBE MaintenanceEditor

Who, me? Yes, you, the engineer,may find yourself conductingpersonal interviews with communityleaders. The survey mandated bythe FCC at license renewal timemust be conducted by managementlevel station personnel throughpersonal interviews. Managementlevel means management in itsbroader sense, and is not limited totitles.

Depending upon station size,many engineering people are inmanagement level positions and arethus eligible to participate in thissurvey.

The license renewal date willdetermine the period of this survey,so this will vary from state to state.The survey creates a heavy additional workload, but if the timefalls within a period of intensivecommunity acitivity, such as theyear end holiday season, the workload is greater yet. During such aperiod, many of the people youneed to interview will be very busyand setting interview times will bedifficult. Besides all the additionallegwork and paperwork the surveycreates, the greatest casuality of allwill be time. This project consumesa tremendous amount of time.

On TheBright Side

Be optimistic and look at the

benefits ...and there are benefits tobe gained. Aside from the information gained on community needsand problems, there is a tremendous potential for stationpublic relations work.

Many of those interviewed, andespecially those in smaller communities outside your main community, will be quite impressed thatyou will personally seek theiropinions. This makes them feelimportant, and in doing so, makesfriends for the station.

Station engineering people aregenerally immersed in technicalproblems and "things" and are notoften in contact with the public.Making these personal interviewscan be a very satisfying experiencethat will broaden the engineer'sviewpoint both as to the public andthe station's responsibilities in thecommunity.

Planning The CampaignPrepare your campaign so that it

can be conducted in a methodicalmanner. Your particular efforts willbe a part of the total station effort.While you may have little to dowith selecting the "panel" of Community Leaders, you may have achoice in selecting the particularnames that you will interview. As asuggestion here, select the names ofthose you do not know personally.This will provide you an opportunity of getting to meet newpeople, and it will keep the survey

Management HighlightsThe requiredcommunity surveywill makedemandsuponyour time, even if you take the adviceof the author. Buthis view, some pre-planningand time organizationwillmakethe effort a lot easier.And, yes, all membersof thedecisionmakingteamcan participate.

26

objective.So that the interviews will be

both fruitful and efficient, preparethose to be interviewed ahead oftime. This can be done through asimple form letter sent to each oneon your list. The station shouldprovide you with such a letter andalso one of the forms that will beused for the interview. Although it'sa form letter, add a personal touchby addressing each letter to theindividual and sign your own signature at the end. This letter will startthe recipient thinking about thecommunity problems and needs,and the interview form will show itsoutline.

You may have been assignedmany people to interview so it willtake some time. It is best to sendout only enough letters at a time tocover one week of interviews. Allowthe letters to be in their handsabout one day and then call themon the phone to set up an interviewdate. Set this date for a day or solater or within a week. This quickfollow up will continue theirthoughts in this area and settingthe interview a few days later willcontinue the process.

In case there are misunderstandings about the interview, you canclear it up on the phone. Somewords convey different meaningsthan intended. The word "interview", for example, in the minds ofmany people means microphones,tape recorders, cameras and exposure over the air. Clear up misunderstandings, but don't get intothe interview itself on the phone.This must be done personally. Youcan suggest that they jot down--onthe form that was sent-their mainopinions and some of the personalprofile data, such as organizationsthey represent. During the interviewitself, you can add to these mainpoints with additional points they




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names of others interviewed, callthem "other community leaders."

A straight question and answertype interview should be avoidedalso. Such an interview will tend todirect the discussion into areas youconsider important. Sometimespeople in sensitive positions maygive you "standard positions" ofthe national organization, or theymay give you opinions that appeared in a recently publishednational poll. If you sense thishappening, ask a few probingquestions so as to determine inwhat manner these apply to thelocal community. While these arevalid in themselves, they may notbe necessarily valid as applied toyour particular community.

To sum up the interview itself:place the individual on stage in thespotlight. You are the audience.The program matter is freewheeling and determined solely bythat individual. This is his opportunity to freely express his own

opinions and in the order he considers them important and in whatrelationship to the community.

You should have an additionalshort form with you so that you canobtain some personal profile information on the individual, such asage, marital status, race, etc. Forthe age question, have this in 5 or10 year brackets. You should beable to guess reasonably close onage. Most of the other informationyou can note without asking also.Another thing you need to know islength of time the person has beenin the community. With women, itis best to pose the question thisway: "Are you a lifelong resident,or have you lived here only a shortwhile?" If you ask a woman howmany years she has lived in thecommunity and she is a lifelongresident, she may balk. To tell youthe years will give away her age.

last? Very busy people will beprepared but won't be able to giveyou too much time, while othersmay desire to talk a long time. Butconsider 15 to 30 minutes asaverage length of time for the interview. Don't allow the interview torun too long as you have scheduledothers to follow. Once it is apparentyou have obtained the mainopinions and talk now begins toramble off into very minor things,start asking some of your profilequestions. This will effectively closeoff the interview. As any goodsalesman knows, once you havemade the sale, don't dally too longbut graciously take your leave.

It may come as a surprise to you,but you will meet many, manypleasant, thoughtful people who aredeeply interested in and concernedfor their community. And this isunderstandable, for it is these veryattributes that made them community leaders in the first place. D

How About Length?How long should the interview

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couraged although, presently, itsuse is optional. Future amendmentof the rules is planned to requirethat this form be submitted witheach type acceptance application. Aseparate copy of Form 723, togetherwith one copy of the informationand data required for type acceptance, should be submitted for eachequipment type number.

On and after July 1, 1973, earlierissues of FCC Form 723 will beobsolete and only the April 1973 orlater issues will be acceptable foruse.

Sept. Date For Video ExpoVideo Expo IV, the fourth

annual international exposition ofprivate, closed circuit and cassettevideo delivery systems and programming, will be held September18 through September 20 at NewYork's Commodore Hotel.

In making the announcement,Eliot A. Minsker, president ofKnowledge Industry Publications,the sponsor of the exhibition stated,"Video Expo has established itselfas the largest exposition of privatevideo systems and programming inthe country. This year's eventpromises to be bigger and betterthan ever.

"Over 3,000 industrial televisionsystem operators, instructionalTV administrators, programmers,dealers and other exectutives activein the industrial, institutional andeducational markets are expected atVideo Expo IV,'' Minsker said.

He explained that the majorvideo industry manufacturers willagain be displaying film and tapecassette systems, cameras, taperecorders, time-base correctors,lights and other engineering andstudio equipment. This year's showwill have a large display of programming.

A unique feature of Video Expois that two major video workshopsand the second annual VideoPublishing Conference, will be heldsimultaneously with the exhibition.Media & Methods Magazine will

sponsor a workshop aimed at theeducational media specialists.Smith Mattingly Production ofWashington, D.C. will coordinatethe workshops which will emphasizesubjects such as the Operation of aSingle Camera VTR System, VTRFeedback and several "hand-on"sessions.The International Industrial

Television Association's easternRegion will sponsor the other workshop, which will be aimed at videousers who have passed the beginnerstage and use multicamera systems.Signal Analysis, Audio Procedures,Video & Software DistributionSystems and Remove Shows will beamong the subjects discussed.

For further information contactEliot Minsker, Knowledge IndustryPublications, Tiffany Towers, White

July, 1973

FCC RevisionOn Form 723

The April 1973 revision of FCCForm 723 may be used by applicants for type acceptance of equipment. Use of this form is en-

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Part 1 of a series

Basic Digital Logic ReviewBy John Lee

Engineer,Hewlett PackardCo.

From nearly every corner todayyou hear that digital circuits are thekey circuits. And it was obvious atthe recent national NAB conventionthat these circuits truly are popularwith R&D engineers.

Last year this magazinepublished a series of four articleson digital logic, written by StanBusby of Ampex. From theresponse we had to that series, webecame accutely aware that there is- and will continue to be - agreat need for more information ondigital circuits.

When the industry was facedwith accepting the solid state trendin equipment design, there werethose who resisted. The vacuumtubes were such old, familiarfriends that it was difficult to partcompany. Then too, there was somuch new terminology to belearned. And in many cases, theterminology was more difficult tounderstand than the new components.

So it was, then, that we weresettling down to the next stepintegrated circuits-when alongcame logic circuits. Taking a hintfrom industry history, the editorsdecided to start at a very basic levelin digital circuits in order that theyonce and for all could be understood and handled. Once more wefound a new set of terms. If wecould make the transition fromtubes to transistors, it followed thatwe could understand the extensionof transistors into IC's and thenot-so-new circuits they would buildinto.What it came down to was realiz

ing that digital circuits displayed intheir most basic form certainly arenot difficult to understand. Perhapsthe understanding of digital logic isat first perplexing, but thisshouldn't hold true when we have afirm grasp of the basics. Of course,

32

as you saw in the Busby series andas you'll see in this series, there aresome new symbols that go alongwith the new circuits. But hereagain, you will find that logic circuit symbols are simply a replacement for block diagrams. Once youbecome familiar with their meanings, many prejudicial problemswill resolve themselves.

We feel that, combined with theBusby series, BE's new approach todigital logic circuits will be "must"reading for all engineers.

The world of electronics isbecoming increasingly digital. Thisfact accounts for circuits todaywhich are more complex, compact,and powerful than ever before.Calculators now perform functionsthat previously required a computer, communication systems arecapable of carrying as many as230,000 conversations simultaneously, and computers affect, if notcontrol, many of our daily transactions.

But even the most complexdigital system is based upon a

Logic circuits are springing upeverywhere. Here you see one of ouremployees setting the type for thisarticle on a machine loaded with digital circuits.

relatively small set of simple concepts. By repeated applications ofthese concepts and through today'sintegrated circuit technologies,designs which before challenged theimagination now become realities.

Because of this revolution, it isimportant that anyone involved inthe design, testing, producing, orservicing of electronic equipmenthave a knowledge of the fundamental concepts of digital electronics. This series of articles is meantto provide an introduction to digitallogic and circuitry. With this background, the reader will be able tostudy more complex circuits andsubjects.

Logic ConventionsThe most common form of

digital system in use today is thebinary system. The informationcontained in a binary digital signalis quantized to two states. Thebasic information unit, the bit,represents the state of the digitalsignal at any fixed point in time.The two possible states of a bit are

..., ""'tf!U&:t~ (l_t

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20 Pt Helios Ug1t1

2!J P,t 1-11?/ins/faff(:

~0 I'!_ I _'-LI1'\/I \\)\I! i \I'_

Here is a closeup of the left side ofone of our typesetting machines. Notice that there are no less than threedifferent types of readouts in use.




Why we've startedwearing the star.

You may have noticed a new symbol on ourcover or index page: the star of the American Business Press.

This star means we've been elected to join aselect group of business and professional journals in a specialassociation. And it means something special to you.

How we earned our star.As a memher of the American Business Press, we

have pledged to uphold the highest ethical standards ofjournalism. Which means we are dedicated first and foremostto your interests as a professional reader by (1)strivingconstantly for honest and effective presentation of all newsand articles, (2)maintaining absolute editorial independenceand (3) refusing to accept any advertising we know to befalse, misleading or unfair.

Let our symbol be your guide.Of the 2,335business magazines published today,

only 30 percent meet the stringent qualifications for ABPmembership. So look for the star in selecting your professionalreading. It's your guide to the finest magazines in nearly everybusiness and professional field. ~

We're proud to have earned MemberAmericanour star and proud to recommend any Business

publication that wears it. Press

July, 1973 33



commonly associated with the "I",yes. assertion. or true condition andthe "O". no. negative or falsecondition. Other associations arepossible but these are the mostwi d c ly used. In the electronicsworld. the "I" and "O" aregenerally used to denote the twopossible states.

In reality. the state of a bit isdetermined by the relation of thedigital signal to a predeterminedcondition. Most commonly thisrelationship is the voltage amplitude of the digital signal to a givenvoltage threshold (Figure I). Due toinaccuracies in determining exactvoltage levels and in order toincrease the digital circuitsimmunity to noise, two thresholdvoltages are often used.

If the digital signal amplitude isgreater than the high voltage threshold. the bit is said to be in thehigh state. If it is below the lowthrcshold voltage. the bit is said tobe in the low state. At pointsbetween the high and low thresholdvoltages. the bit's state is unlined.

Two conventions exist for logically interpreting a bit's state. Themost widely used is the "positivetrue logic" convention. This statesthat a bit in the high state will beinterpreted as a "I" and a bit inthe low state will be interpreted asa "O".

Not so wid e ly used is the"negative true logic" conventionwhich states that a bit in the highstate will be interpreted as a "O"and a bit in the low state will beinterpreted as a "!". It is important to remember that regardless of which convention is used tointerpret a bit. the actual signallevels are unaffected. A positivetrue logic "I" is the same as anegative true logic "O". Both represent a bit in the high state.

Because of the wide acceptanceof positive true logic. this convention will be used throughout theremainder of these articles. Byremembering that a positive truelogic "I" equals a negative truelogic "O". one can easily adjust tonegative logic whenever it isencountered.

Truth TablesTo describe the operation of a

34

digital device, a truth table is used(Figure 2). Since each input canexist in only one of two states, it ispossible to record all input combinations. For an N input devicethere are 2N possible input combinations. A truth table lists theresulting output state for each ofthe input combinations. The truthtable may be expressed in either bitstates (highs and lows) or aspositive true or negative true logicinterpretations (I's and O's). Inpractice the bit state is most oftengiven by the device manufacturersand the positive true logic interpretation used by designers and servicetechnicians. The truth table provides a complete and concise description of a digital device'soperation.

Fundamental DevicesThe fundamental digital device is

the gate. There are five basic typesof gates from which all other digitaldevices are built. These are theJ\ND, OR, INVERTER, NANO,and NOR. In general, a gate can bedescribed as a single or multipleinput device that produces a singlehigh or a single low state output fora given combination of input states.

The symbols used to representthe basic gates are varied andmany. The symbols used in thismaterial represent those mostwidely accepted in practice. Theactual symbol encountered is unimportant, for once a symbol isdefined. the interpretation and useof that symbol to represent a welldefined digital device is simple.

The AND gate is a multipleinput device. It produces a lowstate output only when all inputsare in the low state. Another way ofan N input AND gate will producea high state output only when inputI and input 2 and ...and input N arein the high state, hence the termAND gate.

The OR gate is also a multiple

input device. lt produces a low stateoutput only when all inputs are inthe low state. Another way ofsaying this is that the output ishigh whenever input I or input 2 or...or input N is high. hence theterm OR gate.

The INVERTER is a single inputdevice that produces a high stateoutput when the input is low and alow state output when the input ishigh. From these three ¡l~tes, theAND, OR and INVERTER, allother digital devices can be implemented. But for flexibility and tobe consistent with actual devices inuse today it is important to add theNANO and NOR gates to our listof fundamental devices.

The NANO gate is an AND gatewith its output inverted. That is,the NANO gate produces a lowstate output whenever all inputs arehigh and produces a high stateoutput otherwise.

Similarily, the NOR gate is anOR gate with its output inverted. Itproduces a high state output whenever all inputs are low and a lowstate output whenever any input ishigh.

Demorgan's TheoremWhen analyzing digital circuits

and observing the sym bots used torepresent these gates, it is important to know certain rules ofequivalence. As is inferred in thesymbol for the NANO and NORgates, a small circle on a gate'sinput or output indicates that thatsignal is inverted. For example, thefollowing symbols are equivalent:

=D- ~Figure 3 illustrates another set ofimportant symbol equivalences.From the bit state truth table, wesee that an inverted input OR gateis the same as a NANO gate andthat an inverted input AND gate isthe same as a NOR gate. This isknown as DEMORGAN'S theorem.

Management HighlightsDigital circuits are finding their way into countless broadcast equipments. There is no need to avoid the basics. Youcan start here and be as up to date on the state of the artas anyone.




HIGH THRESHOLD

! 11 n n n DIGITAL SIGNALVOLTAGE ILOW THRESHOLD~

I L___j LVOLTAGE -- LJ lJ I Fig. 1 The relationship of the

I I I I I I I digital signal to the bit stateBIT STATE and the positive tn,e logicH H H H L H L H L

interpretation of the Bit state.I I I i I IPOS. TRUE ~OGICo l I l l o I o l o

I I I I I I I I I INEG. TRUE '.OGIC1 n 1 n 1o o o o

INPUTS OUTPUTS BIT STATE TRUTHTABLEL L H HL H L LH L L HH H H L u

INPUTS OUTPUTS POSITIVE TRUE LOGICo o I 1 INTERPRETATION

o I o o TRUTH TABLE

1 o o 1I I 1 o

INPUTS OUTPUTS NEGATIVE TRUE LOGIC

I I o o INTER PRETATl ON

I o I I TRUTH TA BLE

o I I oo o o I

Fig. 2 Truth table representation of the logical transfercharacteristtcs of digital devices.

By remembering these equivalencesit should not be confusing when aninverted input OR symbol is usedin a circuit schematic while thedata sheet of the actual componentshows a NANO gate symbol. It iscommon practice today to useequivalent symbols on schematicswhen they simplify understandingof the circuit's operation ratherthan the data sheet logic symbolwhich, if used, may cause confusionor misunderstanding.

Combinatorial LogicThe fundamental gates discussed

thus far are part of a class of

July, 1973

A~F:=L)-F = B~

A B

A B F Iio o l 1o I I l o

o 1 - I I oe

=o- F _ A=L>--FA -

BB

A B F liA BO O ! I OO I íl O O

o ll ¡ OI)

Fig. 3 Demorgan's theorem. From the truth tables beloweach symbol you can see that an inverted input OR is thesame as a NANO, and an inverted input AND is the sameas a NOR.

Fig. 4 Binary to decimal decoder.The line corresponding to the decimal equivalent of t t e inputs BAgoes high and all other inputsremain low.

35



digital logic known as combinatorial logic. Combinatorial logic is.the set of devices or circuits whosecurrent output state depends onlyupon the current state of its inputs.Combinatorial logic has no storageand no memory. Combinatorialdevices are easily characterized bytruth tables and logic diagrams. Alogic diagram is a functionallyequivalent circuit composed offundamental gates. Through studyof a device's truth table and logicdiagram, any combinatorial devicecan be analyzed and understood.

GatesCombinatorial devices can be

classified into four main categories-gates. decoders, linedriver/receivers, and MSl/LSI*devices. An important combinatorial gate not yet discussed butwhich often appears in logic dia-

grams is the exclusive-OR gate(XOR) .

Under the strictist definition, thisdevice is not a true gate but rathera more complex circuit. In practicethough it is usually referred to as agate. The XOR gate is a two inputdevice that produces a high stateoutput when its inputs are different. An XOR is thus a digital bitcomparator.

The AOI (AND-OR-INVERT}gate is another complex gate in thecombinatorial logic family. Thelogic diagram and truth tableshown illustrate that the output ishigh only when at least one input toeach AND gate is low. The AOIgate is very useful in binary adders,subtractors and other computercircuits.

Buffer gates provide extraordinary output drive capability inaddition to performing the same

logical function as the AND orINVERTER gates. These devicesare used to interface digital logicfamilies of different voltage levelsor to provide increased drive capability within the same logic family.Quite often the outputs of thesedevices are tied in parallel toprovide this extra drive capability.The 7406 Hex Inverter Buffer is anexample of a TTL buffer gate. Itallows TTL deviceds to be interfaced to MOS and extends themaximum current sinking capability to 40 mA, more than 20 timesthe ability of a normal TTL gate.

Some logic families also includeexpander gates in their productline. In general, these devices arenot gates but rather analog circuitsused to increase the effectivenumber of inputs to another gate.Often the outputs do not meet thedefined output threshold levels.

AND gate

AA

HH I LH

BIT STATETRUTHTABLE

POSITIVE TRUE LOGICTRUTHTABLE

OR gateA A

HHH I H

BIT STATETRUTHTABLE

POSITIVE TRUE LOGICTRUTHTABLE

INVERTER

Fundamental Logic DevicesSYMBOL NOR gate

BIT STATEfRUTHfABLE

A SYMBOL

PQSlflVE fRUE LOGICTRUfHTAALf

SYMBOLINPUTS

XOR (Exclusive OR gate)

INPUTS

OUTPUT OUTPUT SYMBOl

A B e o f

o o o o Io o o I Io o I o Io o I I oo I o o Io I o I Io I I o Io I I I oI o o o II o o I II o I o II o I I oI I o o oI I o I oI I I o oI I I I o

AOI (AND-OR-INVERT)SYMBOL

f----{>-1- OR ~

NANO gate

A

BIT STATETRUTHTABLE

POSITIVE TRUTHLOGICTRUTHTABLE

36

SYMBOl:=e>-r-




They are sufficient, though, to drivethe inputs of certain other gatesknown as expandable gates.

The 7460 is an example of a TTLexpander gate. This device ismerely a TTL input transistorfollowed by a transistor with openemitter and collector. Its outputswings between .4 and .8 Volts.This is not a defined TTL signal.

DecodersDecoders are multiple input,

multiple output devices whichaccept a predefined set of inputsand produces a predefined set ofoutputs. Figure 4 shows a simplebinary to decimal decoder. Theinputs BA represent BCD numberwith A the least significant bit. Theoutputs O through 3 correspond tothe decimal equivalent of the BCDinput. For example, 10 is the binaryequivalent of 2 and thus output 2will go high when this input ispresent and all other outputs will

LOGIC DIAGRAM

TRUTH TABLE

INPUT OUTPUT

WHEN WHEN

c1N·O CIN ·I

A¡ Bt A2 B2 £¡X2Cz X1l~£BL L L L L L L HILÍLHLLLHLLLH----- - .__l;;..__ 1--·+--+--+-L H L L . H L L L H LHHLLLHLHHLLLHLLHLHHLH L H L H H L L L HLHHL'HHLLLHH H H l L L H H L HLLLl9LHLHHLH L L H" H H L L L HL H L H H H L L L HHHL_HLLHHLHLLHHLLHHLHHLHHHLHLHHLHHHHLHLHHH H H H L H H H H H

"- X¡

Logic diagram and truthtable from a 7482 data sheet.These are basic tools neededto analyze· combinational devices.

July, 1973



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remain low. Other decoders includeEXCESS 3 to DECIMAL, BCD toSEVEN SEGMENTS, and BCD toDECIMAL.

Line Driver/ReceiversLine drivers are semi-analog

devices which generally performsome gating function on the inputand provide the result on differential outputs to drive a twistedpair line. The outputs are currentmode and do not swing between thedefined threshold levels. Linereceivers are high input impedance,high sensitivity devices used todetect the differential signal and toconvert it to a signal compatiblewith the logic family being used.

MSl!LSIThere are many other combina

torial devices of a much morecomplex nature. These are usuallyreferred to as MSI (medium scaleintegration) or LSI (large scaleintegration), depending upon thedegree of complexity of the device.Some such devices are MAGNITUDE COMPARATORS, PARITYGENERATOR/CHECKERS, ARITHMETIC LOGIC UNITS, LOOKAHEAD CARRY GENERATORS,DATA SELECTORS/MULTIPLEXERS, FULL ADDERS andmany more.Since it is impossible to discuss

each and every one of these devices,we will analyze in detail one circuit,the 7482 2 BIT BINARY FULLADDER and state that the techniques used can be applied equallywell to the other devices.The basic tools used to analyze

any combinatorial device are thetruth table and the logic diagram.On the data sheet for the 7482, thebit state truth table is given. Thisgives a complete and concise statement of the device's operation.From this table one can see thatthere are 5 inputs Al, Bl, A2, B2,and Cin· The arrangement of thistable is slightly different from thatdescribed before. The state of theCin input determines which row ofoutput states are to be used. This isequivalent to including the Cin inthe input column as done pre-




Phasing For Stereo PBWith emphasis on better quality

these days the following procedurefor proper phasing of stereo playback units should be helpful.

Normally a test tape is placed onthe machine in question and theazimuth rotated for maximum outat say 10 kHz or so. This is fine forsingle track recorders, but with twotracks even after this adjustmentthe phasing can be off enough tocause a drop of several dB. With ofcourse the same information onboth tracks.

I suggest you make a test tape onyour master machine by the following method. Connect your audiooscillator to your recorder with onechannel 180 degrees out of phasewith the other. This can be donewith a 500-500 Ohm transformerwith the secondary reversed. Recordboth channels simultaneously, for a1000 Hz tone for two minutes, then5000 Hz for two minutes. Thiscompletes the test tape.

Place the recorded tape on yourPB machine to be adjusted. Nowhere you will need a method ofmonitoring both channels in a

mono condition. The level of theplayback amplifiers should beequal.

Play the I kHz portion of the testtape and adjust the PB head for anull on the test VU meter or in thephones.

The audio in channel A will beequal and opposite to that inchannel B, causing them to cancel.Figure 2 shows the output whichresults with mis-alignment.

Move to the 5 kHz portion of thetest tape and adjust for furthernull. With a good quality recordedtape (and good heads) you shouldbe able to adjust for zero outputwith proper alignment.

Perhaps the people who recordthe various music tapes will comeup with a test tape for your PBmachine in your automated systems.

Thomas J. ArledgeAsst. Chief Engineer

Birmingham Area ETV Studio

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An update on phase monitorsBy Bob Jones*

BE's Facilities Editor brings you upto date 011the directions the FCC istaking on a11te1111aphase monitors.

This article concludes my threepart story of the FCC's changes inthe antenna monitor rules and regulations. The following commentsrelate to Docket #19692. It shouldbe noted that the FCC has not concluded this Docket yet.

As a result of all the commentsfiled in reply to Dockets #18471and #18455 the FCC has finallyrecognized that some standardsshou Id be set for the design andinstallation of sampling systems forantenna monitors used by standardbroadcast stations employing directional antennas. The FCC asked byNotice of Inquiry dated February21, 1973 for comments by interested parties on the standards setforth in the Appendix attached tothe Docket. But first let me give alittle history on this third Docket.

DocketPerspective

The antenna monitor is an instrument utilized to provide indications of the relative phases andamplitudes of the currents in theelements of a directional array of astandard broadcast station. Such amonitor can furnish much of theinformation necessary to insure theproper maintenance of the station'sradiation pattern, which is essentialif a station is to stay where itbelongs and prevent interference toother stations.

In the two previous Commissiondockets and accompanying filings,the FCC amended its Rules andRegulations to establish type approval of antenna monitors and aschedule for their installation by allstandard broadcast stations utilizing directional antennas. Theimplementation of these new rulesmeans that all stations eventuallywill substitute accurate, stable andeasily manipulated monitors, forthe present equipment, much of•BroadcastConsultant/ LaGrange,Ill.,and Facilities Editor o BroadcastEngineeringmagazine.

40

which is obsolete, of doubtful accuracy and stability. Also. some ofthese older types of monitors arecomparatively complicated to operate. This is a special problem nowthat the FCC has permitted lessergrade duty operators at stationswith directional antennas. Thesenew antenna monitors are intendedto give not only more accurateindications, but also to permit-inthe case of remotely controlled stations with a directional antenna-alessening of transmitter inspectionrequirements.

Coupling ComplicationWhile the FCC has provided a

solution to improved instrumentation at all stations, one further stepis necessary ..... or, so the FCCstates, if we are to realize the fullpotential of the modern antennamonitors.The signals which activate the

antenna monitor are samples of thecurrents flowing in each tower ofthe array. These samples are obtained from coupling elements,usually mounted on each individualtower. The individual signals aredelivered, by transmission lines(usually coaxial cable), to the antenna monitor located in the transmitter house. Each line may be upto several hundred feet in length. Ifthe antenna monitor is to be reliedupon for accurate and stable indications of relative phase and amplitude, it is essential that any samp-1ing system be so designed thaterrors in indication, due to inadequacies in the system be minimized.

Many of the comments filed onDocket 18471, particularly from experienced consultants and technicalpersonnel of broadcast stations,emphasized that the sampling systems presently employed in manystations are clearly of poor design,or have deteriorated through lackof adequate maintenance. And suchpoor systems can often introducelarge and variable errors in monitorindications. These can be due tochanges in temperature, wind velocity, humidity and other factors.Many of these engineers urged theFCC to establish at least minimum

standards for the installation andmaintenance of sampling systems.This of course the FCC admits

to, and as they stated in Docket#19692, was the reason for thislatest Notice of Inquiry. In settingforth possible sampling systemstandards, the FCC drew extensively from the information and suggestions submitted in Docket #18471.The FCC hopes by this only toestablish minimum and essentialrequirements for a properly designed sampling system. They hope atthe same time to avoid the imposition of unnecessary restriction onthe prerogatives of consulting engineers who design the systems .....or to place undue and costly burdens upon station licensees.

GettingThe Job Done

A number of questions immediately present themselves. For instance, should temperature stabi-1ized cable be specified for allsampling systems? Also should allJines be required to be of equallength? Should only rotatable and/or shielded loops be installed in allinstances? Should only loops berequired, even for quarter-waveheight towers? Should all samplinglines be required to match theirimpedance?

Undoubtedly engineers who havehad extensive experience withinstallation, maintenance and useof such sampling systems will havestrong opinions on these pornts.

In addition to these basic questions, the FCC is also looking forsuggestions on comparatively simpleand practical test procedures whichmight be employed periodically,perhaps at the time of the equipment performance measurements(Section 73.47) to ascertain that nodeterioration has occurred in thesampling system.The effort initiated by the FCC

in this last Docket on antennamonitors and sampling systemstandards may be viewed as anaction at variance with the Commission's avowed purpose, as expressed in its Public Notice of April6, 1972. This Notice, you may




recall, states that the FCC wasgoing to simplify and-where possible-relax the regulations governing the broadcasting services. In thelong run, the FCC points out, thistightening of sampling systemsstandards is aimed toward that end.The FCC's logic is that by usingthese new tighter standards, it maybe feasible to relax certain existingoperating requirements.

Since the general use of stableand accurate antenna monitoringsystems by stations with directionalantennas will substantially reducethe incidence of out-of-adjustmentsystems. Re-adjustment is a sourceof considerable trouble and expenseto many stations.

The FCC suggests that one of theresults possible in the future will beless frequent intervals at whichmo ni t o r points have to be measured. In fact. it might be possibleto rely completely on antennaratios. with the elimination of therequirement for reading base currents. Many consultants have realized that with half-wave towers,remote ratios are more accuratethan base currents.

The FCC broke down their Appendix in Docket #19692 into twogeneral areas. These are SamplingLines and Sampling Elements. Letme now go over each of thesepoints along with my thoughts proand con.

The first standard proposedunder Sampling Lines is that alllines shall be of equal total lengthswith equal portions of the linessubject to the same environmentalconditions. This would make thecable people happy since theywould sell more cable. But it hasbeen my experience that most consu 1tan ts now prefer equal lengthlines. There are two very goodreasons.

By having equal length lines, themeasured phase angles will workout in practice very close, if notidentical with the theoretical phaseangles. This is useful, since it givesyou a better idea of how close youare to the true pattern. Anotherreason is that equal length lines willcause the same error to be introduced into all lines when the temperature of the cable changes. Allprudent engineers have recognized

July, 1973

for years that coaxial cables expandand contract and that the electricallengths change as the temperatureof the cable changes. (In some casesI've seen a cable change by 15-20degrees.)

What are the disadvantages tothis standard? Obviously, it costsmore money to the operator whowants to use direct, unequal lengthcables. And it must be recognized

that some systems with unequallengths do not show wide changesdue to environmental conditions. Asecond point against equal length isthat it prevents the design engineerfrom adjusting the normal positionon the monitor where a reading islogged. What often happens is,when, during a tuneup, the phaseangle turns out to be close to zeroor 180 degrees. the engineer will

Paragraph 73.69of the FCC's Rules and Regulations states:... every standard broadcast station employinga directional antenna must usea type-approvedphase monitor.

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add or shorten that sampling lineso that the phase can be read moreeasily so that minor changes invalue are easily detected.

A Line OnSampling Lines

The second standard suggestedby the FCC is that all samplinglines shall have solid outer conductors with either air or polyethylened ielectric, so proportioned as toproduce a minimum phase temperature coefficient. Here again therule seems to favor the cable manufacturer. Price-wise a typical soliddielectric type Heliax (5/8") cablesells for about 74 cents per foot.Their same (5/8") air dielectric,model Heliax sells for $1.22 perfoot. When you realize that moststations now employ either RG-11Uor RG-8U cable, at $ .16 per foot;the reason is obvious. Cost!

You have to look further into theFCC's reasoning on this suggestedstandard. One positive reason isthat solid outer conductors providea higher degree of shielding. Andsecond, these solid conductor type

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cables have less of a temperaturecoefficient than RG-8U or RG-11Utype cables.

Most broadcasters have foundthat the difference in shielding effect between braided and solidouter conductors is nil. But even ifit weren't, the fact that most operators now bury their sampling cablesseveral feet below ground completely eliminates the question of whether any stray signals get into thebraided type cables. Also, the factthat most operators now bury theircables stabilizes temperature effectsand makes their RG-8U andRG-11U lines just as good as thesolid type cables.

The third standard proposed isthat all sampling lines shall haveidentical electrical characteristics.This is generally the practice followed today by most stations. Whena new station is built, usually allthe sampling cable is purchased atthe same time from the samesource. If so, then it would meetthis proposed standard. The onlyplace where one might get intotrouble on this score is where hehas had older cable that is nolonger manufactured. Now let's sayone of his lines is damaged by iceor fire and it needs to be replaced.It certainly is unfair for him tohave to replace all his samplinglines, just because one cable became defective and that type of lineis no longer manufactured. A morereasonable approach would be topermit the licensee to install asubstitute cable of approximatelythe same characteristics and of thesame electrical length.

Laying the LineThe fourth proposed standard

under sampling lines states that theportion of lines between the towersand the transmitter house shouldpreferably be buried. Or, if runabove ground, the lines shall berigidly supported and positioned.What's more, the outer conductorsshall be grounded at points necessary to insure that field from thearray will not induce error currentsin the lines.Of the four standards proposed

under Sampling Lines, this is theeasiest for station owners to complywith. Most stations are alreadyburying their cables to protectthem, to stabilize their temperature

variations, and to eliminate theabove ground maintenance problems.

In the case of stations wheredirect burial is not possible, it isjust common sense to securely tiethese sampling lines to a messengerline or other rigid device. Likewise,good engineering practice for yearshas been to ground these lines atshort intervals to prevent inducedRF errors. Some engineers haveused a bundling ground wire instead of periodic grounds, since itserves the same purpose.

Sampling ElementsIn the area of Sampling Ele

ments, the FCC has proposed fourspecific standards. These, as thereader will see, generate a lot morecontroversy.The first suggested standard says

that all sampling elements shall bea single turn, untuned , unshieldedloop of rigid construction, withample gaps at the terminals solidlysupported by nonhygroscopic insulators. In effect this says all youoperators who use the Gates orCollins shielded loops will have tochange!

It's been my experience that themajority of stations who use loopsuse shielded loops. The primaryadvantage to such loops is that theypick up only the magnetic signal.Also, restricting a loop to a singleturn will arouse objections fromthose low power stations who foundit necessary to use two or even threeturns within the supporting loops inorder to achieve sufficient sensitivity to calibrate their monitor.

Such things as rigid construction,ample gaps and the use of goodinsulators are only good engineeringpractice and now meet the standards of most manufacturers.The question of "untuned" may

seem like it would cause no howlsfrom licensees. But it will. I concede that very few stations haveresorted to this technique. I presume the FCC's worry here is thatuntuned loops are more stable thantuned. I disagree, especially if thetuned loops were all tuned identically and if their condition is periodically checked.

WERK in Muncie, Indiana hasemployed tuned loops for many,many years with no instability. Certainly, if a station is required to




conduct a yearly recalibration of itssampling system, tuned loops canbe reverified as simply as untuned.

The second standard proposed isthat each sampling loop shall beoriented with the plane of the loopincluding the vertical centerline ofthe tower. and it shall be rigidlymounted on the tower in this orientation. The center conductor of thetransmission line shall be connectedto the side of the loop nearest thetower.

Herc too. I expect howls fromstation operators. One of the reasonsmany owners purchased rotatableloops is so they can be used to helpcontrol the remote amplitude readings. Requiring all loops to be rigidand always oriented to the centerline of the tower will eliminate the"case of adjustment" now enjoyedby such stations. Why the FCC hasstated the inner conductor has tobe connected to the side next to thetower. docs not follow with accepted practice. If this becomes oneof the standards. all those using theunshielded loops will have tochange loops. Also all unshieldedloops that are grounded to thetower can not comply. since if weconnect the inner connector to thetower side of the loop. it will shortout the signal. Thus to comply.nobody can use a grounded loop.which in the past has been thestandard method of installing unshielded loops.

When one employs just a singleturn loop. it really makes no difference at all which side connects tothe tower. Until the loop is closedno current will flow. and once itdocs. it is a constant value in anuntuncd loop.

The third standard proposed forSampling Elements is that all loopsshall be of the same size and shapeand be of identical construction,and shall be located at the sameheight on each tower (if the towersarc of equal height) at a point closeto the current maxim um in thetower. but in no case less than 10feet above ground level.

Probably the least controversialpoint here is the minimum heightabove ground of 10 feet. Almost allloops are at least that high off theground. Of course the logic here isto get the loop high enough to beun effected by vegetation, . snowcover. etc. Some consultants have

July, 1973

insisted on their clients mountingloops a minimum of SO feet up thetower. Good engineering practicehas always dictated that loops beinstalled at or near the currentnodes.

The real howl over this standardwill result because of all loopsbeing required to be equal size.Many engineers have found thatwhen their tower currents arc low.they have had to go to oversizedloops in order to obtain sufficientsignals to calibrate the monitor. Infact. some engineers vary the size oftheir tower loops to achieve equalsignal magnitudes back at themonitor. One special case whereloops have to be of cl i ffcring sizes iswh c n a directional array is composed of unequal height of towersor where one tower is guyed andone is a self supporting tower.

Current TransformerThe last point proposed as a

standard for Sampling Elementsstates that for a tower of less than'/.¡ wa ve le n g t h in height. currentsampling may be obtained from thetransmission line. as close to thebase of the tower as possible. by acurrent transformer or other couplin~ clement.

The basic convenience of the useof current transformers is that theycan be installed in the "dog house"out of the weather. When troubleoccurs. or is suspected. they areeasier to service. The FCC's logic inrestricting these to only thosestations who employ towers of 90ºor less is not too clear. Manystations have used current samplingtransformers on towers up to 120º.

Obviously with a 180° tower thereadings of base sampling will result in a different set of conditionsthan a sampling up at the currentnode.

Well. this brings to a conclusionthis three part series on the FCC'snew phase monitor rules as theyapply to the type approved monitors. how soon each of us will haveto install one. how they affect thosestations operating by remote control. as well as the proposedstandards for sampling systems. Ifand when the FCC does issue afinal ruling on Docket #19692count on BE to keep you informed.Keep an eye on our Direct Currentcolumn. O

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A reportfrom montreux

By Joe RoizenTelegen,Mountain View, Calif.

The biannual symposium heldthis year in Montreux (May 18-24)has become the NAB of Europe. Itattracts as delegates members fromthe TV broadcast industry from allover the world, including the USA.It is also the show place for themost producers of TV originatingand distribution equipment andEuropean representatives.

Since its inception in 1960, it hassteadily expanded in scope andattendance so that it is now theforemost international platform fortechnical presentations and thelargest exhibition of broadcastindustry products.

Paradoxically, this small Swisslakeside resort would seem to havenothing to attract a global conference of this caliber. Montreuxcannot boast central commerciallocation like Chicago, nationalcapitol status of Washington, D.C.or the program production facilitiesof Los Angeles. Instead it offersfunny funiculars that run up anddown the nearly perpendicularmountains, quaint chateaus thatdate back to the middle ages andall the fondue and dole the delegates can consume. Except for afew new high-rise hotels thatplagerize the Hilton or Sheratonchains, most of the accommodations carry names like Grand Palaceor Suisse Majestic and ensconcetheir patrons in the faded opulence

44

of late 19th century luxury. Thisincludes exposed plumbing andgrill work balconies overlooking LacLeman (Geneva) with its splendidbackdrop of snow capped Frenchmountains on the other side.The emergence of Montreux as

the cultural and technical wateringhole for such renowned events asthe International Jazz Festival,Rose D'Or TV Festival and other isthe result of a clever decision onthe part of the city managementback in 1960. The highly seasonaltourist trade was extended into themonths proceeding and followingthe mid-summer migrations ofmassess of English tourists. In thisway the duty cycle of the availablefacilities would be expanded intomore profitable utilization.The first Montreux TV

Symposium combined both the program contest and product exhibitsand was held in 1960. It wasscheduled to become. an annualevent. The technical conferenceand equipment display portionimmediately ran into conflict problems with existant electronic conventions, which made it appear thatnot enough momentum could begained to keep the show on theroad.

In subsequent years it was alterna tly boycotted by the UnitedKingdom or Continental manufacturers who. wanted to avoid two

Philips mounted one of their camerason a pleasure boat and beam theirsignal back to shore in a uniquedemonstration. Gates, RCA, and Marconi located cameras on a fire escapelanding in order to provide live pictures to the exhibit areas of thepicturesque scenery.

full blown TV conventions in ~given twelve month period. Thissituation was not unlike that whichis now being experienced by theU.S. TV manufacturers in havingto marshall their forces for NABand NAEB that are approximatelysix months apart.

The International BroadcastingConference in London was beginning to grow as were some of theregional TV expositions and annualtechnical fairs in Paris and Berlin.In evaluating the situation theMontreux Chamber of Commercemust have decided that half a loafwas better than none and come upwith the logical compromise whichhas served to enhance the desirability to the broadcast industry ofparticipating in this convention.The symposium was scheduledevery second year, alternating withIBC in London.This year's technical exhibition is

enhanced by four separateoccurances. First, the general economic well being, particularly inEurope, is creating a good marketfor color TV studio equipment.Second, the United Kingdom's




Or did you know that Bosch was into CATV and MATV systems?

entry into the common marketmakes British products more competitive in a number of new areas.Third, the old Montreux Casinowhich housed the exhibit equipment was destroyed by fire and apublic subscription raised by localresidents produced a modern newexhibit hall which is now the site ofthe equipment display. Finally, thediminishing trade barrier betweenEast and West is creating a significant television product flow intoEastern Europe and the SovietUnion. Large color mobile vansdestined for delivery at the close ofthis exposition carry logos such asTelewizja Polska Kolor, Televiziunea Romana etc.

Equipment ExhibitsThe new Montreux Maison des

Congres is a four floor low profilebuilding with a unique internaldesign. It has areas of multi-levelopenings for the larger exhibits andsections of single level cubicles forthe smaller one's. Outside, thecanny Swiss have used a metalcovering that has been allowed torust, thus providing a warm browncolor to the whole building: Paint(as everything else) is exorbitantlyexpensive!!The only significantly new piece

of major television originatingequipment being displayed was theIYC built 9000 helical scan broad-

July, 1973

cast recorder. This machine is ajoint venture between IVC,Thomson CSF and Rank Cinte) andrepresents major competition forthe quadruplex video tape recordersthat now dominate the broadcastmarket. There were two 9000machines operating in PAL andSecam, permitting demonstrationsof full interchange, even on 100percent saturated color bars.Gates demonstrated their TE-201

cameras, their BT-1300H 1 kWtransmitter, their program automation system. Gates' equipmentand facilities expansion programhas brought them into position as amajor full line contender as a TVequipment manufacturer.

Fernseh was featuring the KCRportable color camera and RCAwas emphasizing the cartridgerecorder as was Ampex. Thomsonhad a very elaborate stand, complete with a night club revue imported from Paris, multiple cameracoverage, control room with switching and special effects.The Philips display was the most

elaborate, in terms of set design,including multiple story structures,carefully planned shows with complex chroma keying and peripheraldisplays of non-broadcast equipment (CATV, Cassette, etc.)Mobile units were having a big

year. Multi-camera units made bythe major su pplier were parked

Dynair, alcrg with a number of otherAmerican manufacturers are shown inthese pictures preparing for the opening of the exhibits. There are a numtier of others not shown in thesepictures, among them, Gates, IVC,RCA. Gates demonstrated their newTE-201 camera, their TV transmitters,and their "touch control" digital program automaiion system. Gates presented a technical paper on TV IFmodulation, and other manufacturersas well played a major role in presenting the US TV state of the art.Unfortunately, pictures of more exhibits were not available at press time.

45



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cheek by jowl next to the buildingand provided continuous coverageof the passing scene. There waseven one mobile van produced inPoland and displayed by UNITRA,the Polish export agency.

New lenses with ever increasingzoom ranges were everywhere supplied by Canon, Angenieux, RankTaylor Hobson, Schnieder andothers. The technical symposiumincluded a wide array of paperscovering general revues of the progress of television in variouscountries and very specific detailson new technological features of theequipment on display. The lecturehall was not the best for thispurpose but it was equipped withaudio visual aids which included anEidophor large screen projector andan AVRl for tape playback. Majorlectures were well attended by up to300 delegates.

Aside from the normal technicaltalk that goes on at a symposium ofthis type, the major topic of conversation was the seemingly suddenskyrocketting of prices for almosteverything a company or participant needed at this show. Montreuxhotels were choked with AmericanExpress busses disgorging endlessgroups of tourists. As a result,room rates and meal prices justspiralled out of sight. It was notunusual to pay $30 or over for asingle room (with bath) or $6 to $10for a mediocre meal poorly served.This is a far cry from the attractions that once made going toMontreux a high point in televisionactivities. O




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This book is available through Howard W. Sams &Co .. Inc .. Indianapolis, Ind.


Light Emitting Diodes/\s early as 1907. emission of light from a semi

conductor was produced by application of a lowvoltage potential to two points on a crystal of carborundum (silicon carbide). This discovery has onlyrecently attained commercial application in the form ofthe light emitting diode (LED). The advantages of theLED over the conventional light sources (incandescentand fluorescent lamps) are solid-state reliability, speedof response. and compact size. Some of the applications for which the LED is particularly suited areminiature panel indicators. digital readouts, light-beamcommunication, optical radar. and logic status indica tors.

Light emitting diodes have been developed to emitlight in several different colors, mainly reels, oranges,and yellows. with others in the development stage. Thecolor wavelengths are quite narrow; thus, the need forfilters is kept at a minimum. LED's have also beenconstructed that emit in the infrared portion of thespectrum.

Light Emitting Diodes, written by Forest M. Mims,III. covers the topic of light emitting diodes thoroughly. starting with the theory of semiconductor emissionand details of physical construction. then chapters aredevoted to the infrared-emitting LED and the visiblelight-emitting LED.

Chapter 4 discusses the use of the LED as a displaydevice. with such applications as digital display,alphanumeric display, polarity and overflow displays,logic displays. and others. Chapters 5 and 6 deal withaccessory devices necessary to make full use of thelight provided by the LED; detectors, receivers, andviewing devices. and lenses and fiber optics.

This book is available through Howard W. Sams &Co .. Inc .. Indianapolis. Incl.,


July, 1973

All ESEdigitals are designed and constructed using the latest solid stateelectronic components and circuitry. This equipment is perhaps the mosteconomical line of digital clocks, timers and counters available. Circuitefficiency and lasting quality are designed into every ESEdigital product.Constructed with the built-in ruggedness necessary for studio use. Nomoving parts.Special custom items, like the video tape/ counter editor, a monitoringsystem with unique display configuration, 12 and 24 hour clocks ortimers, 10 minute timers, 3 digit, 4 digit, 6 digit, record seconds intenths, hundredths or thousandths ... All available from ESE.Options include: Thumbwheel switch or patchboard programming, BCD outputs,relay closure outputs, and solid state buttered outputs. Many productsavailable in kit form.

MOST EFFICIENT DIGITAL CLOCKS/TIMERS AVAILABLE ANYWHERE:ES-112/124, 12 hour or 24 hour clock: 6 digit - Recordshours, minutes, seconds ... $ 90.00ES-300, 100 minute up/ down counter: Displays up to99:59 - Easy pushbutton: Reset - Count up - Countdown - Advance seconds - Advance minutes - Stop. 135.00ES-400, 10 minute timer: Displays up to 9:59 - Push-button: Start - Stop - Reset 75.00ES-500, 12 hour clock/timer: 6 digit - Records hours,minutes, seconds. Start - Stop - Reset - Slow andFast Advance buttons. Displays up to 12:59:59 120.00ES-510,60 minute timer: Displays up to 59:59 - Push·button: Start - Stop - Reset, Only 3%" deep for flushmounting into walls or std. alum. case 100.00

@.Inquire about our new thumbwheel or

patchboard programmers.WRITE, WIRE OR CALL TODAY:

506 MAIN ST. • EL SEGUNDO,CA. 90245 I (213) 772-6176

For More Details Circle (30) on Reply Card 47



PEOPlE íl~1~m1~Broadcast

Charles Michel has joined Dyma Engineering, Inc.,broadcast equipment manufacture and sales organization to be based at the Los Angeles office....TeleMation, Inc. has announced the appointment of DennisFraser as Regional Broadcast Sales Manager and willbe based at the company's Chicago office....HaroldSobol, of the research and engineering corporate staffat RCA's David Sarnoff Research Center in Princeton,N.J., has been elected general chairman of the 1974Electronic Components Conference sponsored by theElectronic Industries Association and the Institute ofElectrical and Electronics Engineers ....John D. Jackson has been named General Counsel

for American Satellite Corp ....Milton F. Fleming waselected Vice President of Prodelin Inc. at the MayBoard of Directors' Meeting .... Brand-Rex Co. hasannounced the appointments of two salesmen for thecompany's telephone wire and cable product lines.Duncan J. Wilson will cover customers in North andSouth Carolina and western Tennessee. Michael G.McGuire will cover Minnesota, North and SouthCarolina. Nebraska, Wisconsin and Iowa....

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9

Andrew P. McClure has been named Vice President,Manager of Sales for Schafer Electronics Corp ....Robert W. Selvage has been named Sales Engineer andModification Center Coordinator, for the TriplettCorp .... Elmer J. Stymiest has been promoted to anewly created position, Director of Marketing ....Charles E. Hinds has been appointed as ExecutiveDirector of the Chicago Archdiocesan MultimediaCommunications Center and Network (OAMCAN)....Dennis T. Goddard is now Vice President-Marketingand Robert F. Friedman is Vice President-Operationsfor American Satellite Corp ....At the Annual Meeting of shareholders of Penril

Data Communications, Inc., the shareholders electedMerrill Solomon, Alva T. Bonda, Howard M.Metzenbaum, Howard Andrews and Kenneth M.Miller as its directors .... Remi Nadeau has joinedCollins Radio Co. as Director of Advertising andPublic Relations .... Glen Page has been appointedManager, Eastern Region, for Technology Inc., HFPhoto Systems Division....After a 3-year absence, Ivan Ryman has returned to

HF Photo Systems as Director of Engineering ....ElectroSound has announced the appointment of Ted W.Wuerthner to the newly created position of vicepresident, marketing ....Myron F. (Mike) Wilson, director of operations at the Collins Radio Company's plantin Cedar Rapids, has been promoted to vice presidentof manufacturing .... James Wulliman, Manager ofEngineering, Broadcast Division, at WTMJ, Inc., wasrecently elected President of the Society of BroadcastEngineers ....Benjamin D. Wood has recently been named

manager of emitter-coupled logic (ECL) productengineering for Signetics Corp ....Eric King has joinedVital Industries, Inc. as Northeastern Sales Manager ....C.E. "Cliff" Miller, vice president and director ofengineering, Fisher's Blend Station, Inc., owner andoperator KOMO Radio & TV, Seattle, and KATUTelevision, Portland, Or., announced his retirementfrom active day-to-day responsibilities after 31 years ofservice. Miller will continue as Consulting Engineer,exclusively for Fisher's Blend Station. Ralph Mifflinwill become Director of Engineering ....

George Nicholas Simcoe, Chief of the ReferenceRoom Branch of the FCC Broadcast Bureau, retiredApril 13, after 27 years' service .... Rosemary T.Fruehling has been appointed to a four-year term asCommissioner on the New Jersey Public BroadcastingAuthority ....Dr. Melvin G. Holland has been named tothe newly created position of manager of marketingand program development for Raytheon Company'sResearch Div....Philip A. Phalon has been elected vicepresident, international affairs for Raytheon Co....

Sanderling Broadcasting Corp. has named MichaelJ. Corken division vice president and general managerof WAST-TV, (Channel 13), Albany, and Robert BumsTaylor Jr. to the newly created position of division vicepresident for administration and operations ....RebFoster has resigned his position as program director atKRLA Radio, Los Angeles .... Lad F. Hlavaty, directorof engineering for WNAC-TV in Boston, has been




appointed vice president and director of engineeringfor the RKO General Television Division .... Herbert S.Reeves has been appointed Regional Representative forCommunications Technology Corp ....

Richard R. Fried has been named to the newposition of director of marketing for WesternMagnetics, Inc .... Stephen E. Wickstrom has beenappointed Field Sales Representative, Phelps DodgeComm. Co .... Robert W. Coombs has been named localsales manager for KRUX, Phoenix .... The Belden Corp.Board of Directors elected Everett W. Blome and FredO. Weirich group vice presidents .... Lynd John Carterhas joined Lenco Electronics as Sales Manager .... L. D.Altman has been named president of Fabri-Tek Inc ....Robert Cizik was elected President and Chief Operating Officer of Cooper lndustries .... Mark W. Bullockrejoins Continental Electronics Mfg. Co. as VicePresident of Marketing ....

CableIrwin S. Sylvan, manager of national accounts and

operations manager for Anixter Bros., Inc., has beenappointed executive vice president of Anixter-Pruzan ....Les J. Lomax has been appointed CATV sales representative, Anixter-Pruzan ... .John Greenberger wasnamed Director of Programming of TeatreVision,lnc ....Barrie W. Braden has been named ContractsAdministrator for the CATV Equipment & InstallationOperation of GTE Sylvania Inc .... .E. Thayer Bigelow isnow vice president and treasurer of Sterling Manhattan

Cable Television ....Herbert C. Granger has been named to the new

position of Vice President-Operation for United Video,Inc., Northeastern region ....Paul D. Askos has beennamed Manager-National Product Sales for Ameco,Inc....Stuart E. Yeaton, vice president of General CableCorp. has been elected Chairman of the Wire andCable Div. of the National Electrical ManufacturersAssoc. (NEMA) .... Phil Glade has joined AnixterPruzan as a CATV sales representative .... GeneralCable Corp. (NYSE) announced that Donald L. Nivlinghas been appointment general manager of Bare WireOperations ....

Desmond A. Garrity has been appointed vice president and director of corporate planning for GeneralCable Corp .... TeleVision Comm. Corp. (TVC) hasnamed Jay H. Kaplan as vice president-assistantcontroller, and Herbert S. Ornstein vice presidentbusiness administration .... Marcus L. Winchester,southern regional manager for Blonder-TongueLaboratories, Inc., has won his company's third annualKey Man Award for outstanding sales achievement ....Larry Fry has been promoted to the position ofCustomer of Customer Service Supervisor and Phil D.Cook has been appointed Sales Promotion Specialistfor Anaconda ....Continental Cablevision has electedPatrick J. Conley to the position of Assistant VicePresident ....Edward J. Taylor has been named Controller for Big Valley Cablevision, a subsidiary ofContinental Cablevision, Inc.

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chroma keyfrom encoded sources

Chroma key with any composite NTSC signal includingremotes, video tapes, network feeds and single linecameras.We've developed an in-line chroma keyer that is notonly inexpensive but really works. Using a uniquechroma discriminator, noise problems and cross coloreffects are greatly minimized. You might say we'vedeveloped an 'intelligent demodulator'. Both normaland invert keying are possible and the remote controlpanel may be located up to 500' away.We'd like to tell you more and demonstrate this remarkable device. Write for details.

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~~IPRODUCTSProfessionalTape Recorder

The availability of a new highperformance tape recorder forstudio and broadcast applicationhas been announced by Tape-AthonCorp. of Inglewood, California. Thenew recorder/reproducer has several innovative features, of which themost impressive has been designated "electronic editing" by themanufacturer.

Electronic editing allows theoperator to move the tape acrossthe recording heads so preciselythat he may actually "split" musical notes and phrases and avoid thetedious practice of physically splicing tape. This precision control isaccomplished by putting the recorder in a balanced torque modewhich activates the drive motors ofboth tape reels simultaneously and

in opposite directions. In this mode,either reel may be moved manually,in minute increments, without the

the MCMARTIN 10 watt FM exciter

r-tm::I"'3B ·91 O exciter $1995.00 B ·91 OT transmitter $2355.00

ULTRA STABLE with automatic phase-lock sensing

EASILY MAINTAINED with plug-in modular design

CRISP, CLEAN SOUND from latest DCFMdesign-·r-tCD11111111.

.. a brilliant new addition to the "full choice line". The solid stateB·910 is perfect for your new station, your 10 watt educationalapplication or for updating your existing transmitter. This new exciter/transmitter brings you all the professional "know how" that McMartinhas pioneered in SCA/Stereo.Accessories: 8 · 11OStereo Generator $1250. 8 ·113 SCAGenerator $450.

For complete information, please contact: Director of Sales (402) 342-2753

MCMartin4500 south seventy sixth street • ornaha,nebraska 68127 • telex 048·485

For More Details Circle {34) on Reply Card50

creeping effect usually experiencedin conventional machines.For More Details Circle (60) on Reply Card

Sound SystemPower Amplifier

A 100-watt solid-state poweramp lifier.. designated the Model810, is now being made availablefor professional sound applications,it was announced by Electro Sound,Sunnyvale, California. This amplifier joins with other sound components in Electro Sound's completeline for professional sound systems.The Model 810 is now in wide usein theatre systems at such installations as Burbank Studios, American Film Institute, Walt DisneyProductions, ABC Theatres, UnitedArtists Theatre Circuit, AmericanMulti-Cinema, and Cooper TheatreEnterprises.Of all-solid-state design, the

Model 810 is intended for continuous non-attended service in installations where trouble free operationover long periods of time is required.

According to Mort Fujii, generalmanager of Electro Sound, "TheModel 810 has several design features that make it especially usefulfor applications requiring long termreliability. For example, the unithas an internal current sensing circuit which protects the unit fromoverloads and holds its output within safe operating ranges even if anaccidental short should occur. Thisdesign feature, along with massiveoversized heat sinks for the outputtransistors, assures maximum protection and reliability."For More Details Circle (61) on Reply Card

Send your Engineer'sExchange Ideas To:BE, 1014 Wyandotte





MotorizedZoom Lens

A new Neutral Density series ofmotorized zoom lenses designed forLLL television cameras is nowavailable from Canon USA, Inc.,Lake Success, N.Y.The lenses come with gradient

density ND filters built right in,virtually eliminating the defractionlimiting effect. They are availablein four models: V6 x 16RND 16.S-9Smm f/2.0; V8 x lSRND 1S-120mm f/1.3; vio x lSRND lSlSOmm f/2.8; and vio x lS-2 NDlS-lSOrnm f/2.0.Canon's Auto Iris Lens Control

CC21A regulates zoom, focus andiris. The latter, activated by thevideo signal, can close down tof/360 or even f/SOO, depending onthe lens. In addition, the iris maybe controlled automatically ormanually.A dynamic braking system mini

mizes overshoot of lens operation.For More Details Circle (62) on Reply Card

Low Cost12-/nch Monitor

SC Electronics, a wholly ownedsubsidiary of Audiotronics Corporation and manufacturer of SetchellCarlson video monitors and monitor/receivers, recently introduced anew compactly-designed 12-inchmonochrome monitor.

Model 12M918 is a broadcastquality monitor which features Setchell Carlson UTIT-IZED® Plug-InCircuit Modules for rapid, on-thespot maintenance; 100 percentsolid-state circuitry; horizontal resolution of 640 lines; and an amplifier bandwidth in excess of 8 MHz.

Applications include Broadcast,Data Terminal Display, Educational CCTV, Industrial CCTV,Medical, Security & Surveillance,Studio, Remote Installation, andVTR Display.For More Details Circle (63) on Reply Card

Field StrengthMeter

The FSM-1 from Delta Electronics simplifies antenna strengthmeasurements for any AM station.The field strength, from 100µ V/rnto l V/rn, is read directly from the

July, 1973

logarithmic front panel meter. Thecrystal controlled calibration andlocal oscillators are packaged asplug-in modules, eliminating all frequency adjustments. Operation atother frequencies is accomplishedsimply by replacing the modules.Calibrated and certified modulesare available for any AM broadcastband frequency.

Extensive use of field effect transistors and a ceramic lattice bandpass filter assures excellent per-

formance characteristics. The flat,sharp skirt response provides atleast SO dB rejection of harmonic,adjacent channel, and other spurious signals.The unit has an operating weight

of 41/2 pounds, measures approximately S x S x 8 inches, and willoperate for SOhours on 6 standardO-type batteries.For More Details Circle (64) on Reply Card


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Options RGB Chroma Kever • AFVon Program Bus e Processing Amp onPreview Channel • Control cables upto 200' (25' furnished) • SecondColor Matte Generator

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Tracor Model 6500 Visual It's 100 times more stable thanCarrier Generator. Reduces any crystal oscillator system.co-channel interference. Ends routine monitoring, stan-lncreases TV coverage area. dardization procedures, adjustments. Eliminates much external test equipment. Combines the3040 Rubidium Frequency Standard with the 650A TV CarrierSynthesizer. Just plug the 6500 system into the transmitter socketpreviously occupied by the quartz crystal. Without further attention, unaffected by environmental conditions, it will keep yourstation's carrier frequency stable within .05Hz per year. The6500 is FCCapproved and already in wide use. Write or call forfull technical and application information.

Tracor, Inc. 1ndustria1 instruments6500 Tracor Lane s Austin, Texas 78721 •AC 512/926-2800


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from the industry's Creative Product Innovators.TheV11/21AutomaticDigitalLoggerrecordsandprints out all necessarymeter readings. savesvaluable engineering time and assures totalaccuracy.

recordinganalog inputs from singleormultiplesources,andis equippedwith a real-time,solid state. 24-hourdigital clock. Precise time can bedisplayed visually and also printedout.

Here's a complete, self-containedsystem. including a printer whichcan display and print-date identification, time, channel number andmeterreadingsinvolts.amps.watts.etc. The system is capable of sampling, measuring, displaying and

This compact unit is only 7" high.Virtuallymaintenancefree, it utilizesplug-in printed circuit cards forquick and easy replacement. Optional elements and equipmentcanbeaddedforevengreaterversatility.

McBEE LABORATORIES5151 WISCONSINAVENUE.NWWASHINGTON. O C 20016!202!244·2345 !202!244 5535

SpecialElectronicEquipment-for Broadcasting

52 For More Details Circle (37) on Reply Card

~mlPRODUCTS(Continued from page 51)

Dynamic CardioidMicrophone

Beyer announces an addition totheir range of professional microphones, the new M201. This hasbeen developed to meet a demandfrom the TV and Film industriesfor a moving coil microphone withthe same performance and physicaldimensions as the omni directionalBeyer MlOl, but with super cardiode characteristics.The M201 incorporates one of

the world's smallest professionalsuper cardioid moving coil transducers. Overall microphone dimensions are O.945 inches diameter by6.3 inches long. The transducerutilizes a high energy magnetic circuit that gives an EIA sensitivityrating of -149 dBm from a verysmall diameter diaphragm. A special transducer mounting has alsobeen developed to greatly reducehandling noise.A super cardioid microphone, by

the very nature of its sensitivity topopping and breath noise, requirescareful windshield design. To helpovercome these problems the M201has a special sintered bronze breathshield with chromium finish.The microphone also includes a

hum buck coil giving hum rejectionof approximately 20 dB. It has anoverall frequency response of 40 -18,000 Hz. (± 2.5 dB) with sideattenuation at 120 degrees between18 and 22 dB depending on frequency.For More Details Circle (65) on Reply Card

MagneticRecording Films

A new line of acetate-base magnetic recording films, featuring animproved high-output, low-noiseoxide coating, has been introducedby 3M Company, St. Paul, Minn.

The unveiling of Scotch brand337, 338 and 339 Magnetic Recording Films came at the annual meeting of the National Association ofBroadcasters.According to 3M, the improved




oxide coating gives the film a widedynamic range with the same highoutput and low noise characteristicsof the polyester-based Scotch types340 and 341. The new line alsofeatures better resistance to wearand scratching than acetate-basedfilms previously available from 3M.The acetate backing facilitates edgenumbering and editorial markings.

The new films are available infull coat, stripe coat and clear edgeconfigurations for 3Smm and fullcoat for 16mm.

Scotch brand 337 full-coat magnetic film is intended for the mostcritical original recording and mixing applications.For More Details Circle (66) on Reply Card

Audio ConsoleDesigned for broadcast master

control and production studios. The

consoles are available in mono,stereo, and Stereo/Mono modelswith S. 8, or 10 mixing inputs. Features include long life conductiveplastic faders, silent momentarypushbutton audio on/off controlsand machine control circuitry foreach mixer. Power supply rackmounts separately from main console. Available in several attractivewoodgrain exteriors from SystemsEngineering Co.For More Details Circle (67) on Reply Card

Feedback CureFeedback, one of the most worri

some problems common to soundamplification, now may be drastically reduced through the use of anew dramatically effective component announced by Shure Brothers,Inc., Evanston, Illinois.

Called the M610 Feedback Controller, the new unit can be easilyadded to any sound system forrelatively little cost. Operation ofthe M610 requires no specialskills-making it immediately applicable to existing sound systemsin schools, churches, clubs, hoteland motel meeting rooms, pagingsystems and wherever else a soundreinforcement system is presently inuse.

In a typical application, theM6 IO is inserted in the soundsystem between the preamplifier-

mixer and the power amplifier, orbetween the microphone and thepreamplifier-mixer in a singlemicrophone system. Once the M610is part of the system, its special setof variable depth filters and roll-offswitches can be used to smooth outthe peaks in the total system'sfrequency response, so that thesystem gain may be increased tosignificantly higher levels before thefeedback threshold is reached. Theuser is able to "tune" the totalsound system to correct for theacoustic irregularities of the room,to gain maximum output-withoutdanger of generating feedback. TheM6 IO provides the basic advantagesof room-system equalization, butwithout the very high cost involvedin elaborate, complex equalizationequipment.For More Details Circle (68) on Reply Card

July, 1973

Geta betterBangfor

yourbuek!Colortran®Pro-kit iv

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for$398.

Berkey Colortran ~~~~~1015 Chestnut St. Burbank, Ca. 91502 • 213 843-1200




~mlPRODUCTS(Continued from page 53)

Four ChannelProduction Board

LPB Inc., Frazer, Pennsylvania,announces the availability of theirnew S-9B 4 channel mono production board. This light weight (12pounds) unit is constructed ofheavy- gauge sheet aluminum fordurability. The S-9B measures161/i'' wide by 111/i'' deep by 51/i''high. It can be used in a permanent installation, i.e.: newsroom,production studio or mobile unit;as well as for high quality remoteapplications. Features include:• 8 inputs, 2 per channel.• User made adjustments for micor high-level inputs on all channels.• Solid-State circuitry and PCboard construction throughout.• High quality Allen Brac!lleypots.• Internal cue and monitor amplifiers.

• Cue speaker on front. panel.• Front panel headphone jack.• Full spectrum frequency response.For More Details Circle (69) on Reply Card

Alignment TapeThe Recorder Care Division of

Nortronics Company, Inc., manufacturer of magnetic heads andprofessional recording accessories,has introduced a new broadcastalignment cartridge for use withNAB type endless-loop mono andstereo cartridge recorders andplayers.

A product of Nortronics' fast-

54

growing QM-SERIES™ of maintenance accessories, the new AT-320alignment tape is a first generationmaster recording recorded fulltrack at 7.5 IPS. It is engineeredfor routine maintenance of equipment and permits rapid testing andadjustment of Head Azimuth, Program Frequency Response, Program Record Level, Stereo HeadPhasing, Cue Tone Sensitivity andTape Speed. Detailed, easy-tofollow instructions for use are provided with the tape.

Test tones recorded on the AT-320 include: l. 400 Hz., -10 dBFrequency Response; 2. 5 kHz., -10dB Azimuth & Response; 3. 10kHz., -10 dB Azimuth & Response;4. 100 kHz., -10 dB FrequencyResponse; 5. 400 Hz., O dB NABStandard Reference Level; 6. 100 -10,000 Hz. - Sweep, Stereo Phasing;7. 150 Hz. - Cue Adjust; 8. 8 kHz. -- Cue Adjust; 9. lkHz. - CueAdjust; and 10. 1 kHz. - "CueUp".For More Details Circle (70) on Reply Card

We don't give a toot!That's right-we don't give a toot what goes over your horn ... butwe do care that what goes ... gets there.

StainlessMICROWAVETOWERS• Designed and built to meet every requirement.

• No off-the-shelf designs that end up as compromises ortrade-offs. Not less tower than you need nor more tower.They're your towers ...

We'd like to discuss your next tower requirements. Then you'll see

~::~:less,inc.•North Wales, Pennsylvania 19454

Telephone (215) 699-4871In Canada: Walcan Ltd., Toronto 12, Ontario.

For More Details Circle (39) on Reply CardBROADCAST ENGINEERING



BroadcastAudio consoles

Collins Radio Company hasadded eight new broadcast audioconsoles to its broadcast productsline.

Designated the IC-10 (10channel) and IC-6 (6 channel)series, the new audio consoles provide a wide range of features: allsolid-state construction, integratedcircuit preamplifiers, plug-inmodules, 15-Watt RMS monitoroutput, rear or bottom cable entrance, remote control function,stereo and mono headphone jacks,stereo audition, three separatestereo monitor outputs, a minijackinput for cassette players.The new consoles have been de

sign ed to provide versatility ofapplication and custom connfiguration for most AM and FM broadcast needs.

All consoles in the new series arewired for stereo and monauralcapability. Stereo capability can beadded to a monaural console simplyby adding plug-in amplifiers andVU meters. Preamplifiers are interchangeable.

Models in Collins' new series arethe IC-IOSM (ten-channel stereoplus monaural output), IC-lOS (tenchannel stereo), IC-100 (tenchannel monaural with dual channel output), IC-lOM (ten-channelmonaural), IC-6SM (six-channelstereo plus monaural output), IC-6S(six-channel stereo), IC-60 (sixchannel monaural with dual channel output), and IC-6M (six-channelmonaural).The new units are housed in

aluminum cabinets measuring lO"x44"x20" for the IC-10 series andlü"x36"x20" for the IC-6 models.The top cover and front panel of

the units are hinged to provide easyaccess to plug-in modules and components. Connecting cables may beused either at the rear or thebottom of the chassis.

All consoles have balanced transformer isolated inputs, two programchannel outputs, two auditionchannel outputs, and one monauraloutput.

Both the IC-10 and IC-6 (stereoor mono) come equipped withstereo input attenuators that control the left and right channels


July, 1973

Stanton.Benchmark for an Industry.

- """:~~'

Stanton's 681 Series is the Calibration Standardto recording engineers such as Robert Ludwig.

Whatever the requirements for recording and playback, Stanton's Series 681 cartridges are the Calibration Standard. Andthere is a 681 model engineered specifically for each of thesecritical applications. That's why Stanton is truly the Benchmarkfor the industry.

The Stanton 681A-For Cutting Head Calibration. WithStanton's Model 681A, cutting heads can be accurately calibrated with the cartridge, for it has been primarily designed asa calibration standard in recording system checkouts. Frequency response is factory calibrated to the most rigid tolerances and the flattest possibleresponse is assured for precise alignment of recording channels.

The Stanton 681EE--for Critical Listening. Stanton's Model 681 EE is designed forlow-distortion tracking with minimum stylus force, regardless of the recorded velocityor the distance of the groove from the disc center. High compliance, low mass and lowpressure assure perfect safety even on irreplaceable records.

All Stanton Calibration Standard cartridges are guaranteed to meet thespecifications with exacting limits. Their warranty comes packed with eachunit - the calibration test results for that individual cartridge.

For complete information and specifications write Stanton Magnetics,l nc., Terminal Drive, Plainview, L.l., New Yol'k I 1803.

A II Stanton cartridges are designed for use with all two- and four-channelmatrix derived compatible systems.sraxron

For More Details Circle (40) on Repl¡r Card

CBS Laboratories' new Calibration Test Generator puts color to thetest. Providing an extremely stable·signal, the CLD-1200 permits accurate testing, evaluating and calibrating of color television equipment.Digital circuitry insures precision pulse timing.

The CLD-1200's wide range of test signals far exceed industry standards. All test signals are available simultaneously!

The CLD-1200 can even be used as a standard sync generator. FromCBS Laboratories, of course. ,

CBS LABORATORIESADivision of Columbia Broadcasting System, Inc.227 High Ridge Road, S~mford, Connecticut 06905

For More Details Circle (41} on Reply Card 55




~mPRODUCTS(Continued from page 55)

simultaneously.The inputs to channels 1 through

8 OC-10) or 1 through 5 (IC-6) areconnected through two-positionselector switches. Inputs for channels 9 and 10 (channel 6 for theIC-6) are connected through multiposition selector switches. Theseinputs are intended for remetelines, although any type of inputincluding microphone may be accommodated.A total of six stereo lines may be

selected by each of these channels.Optional XL connectors are available for console inputs.

Each channel position consists ofthe two-position input selector, adual rotary attenuator (stereo) withcue position, and a program key.Speaker muting is provided throughthe program keys. Pushbuttons forremote control of starting functions'etc., are conveniently located belowgain control.

Monitor circuits allow monitoringof signals processed by the console.Signals on the cue bus are amplified by the plug-in cue amplifierand applied to the internal cuespeaker. Signals on program, audition, and external monitor busescan be selected by the monitorselector switch, adjusted by themonitor level control, and amplifiedby the plug-in monitor amplifiers.For More Details Circle (71) on Reply Card

Solid-State ScopeWith the new Heathkit I0-104,

the Heath Company introduces aservice bench oscilloscope designedto meet the needs of contemporaryelectronics.The vertical bandwidth of DC to

15 MHz satisfies the requirementsof most laboratory, quality controlor trouble-shooting applications.Vertical sensitivity of 10 mV/cm,and 12 calibrated vertical attenuator positions up to SO V/cm accommodate a broad range of inputsignals.Any one of 22 calibrated time

bases from 2 s/cm to 0.2 us/cm (XSmagnifier for maximum sweep of

40 ns/ cm) can be selected to provide accurate frequency measurements. The horizontal amplifieraccepts external inputs from DC to1 MHz.A stable triggering circuit pro

vides solid waveform displays. Trigger controls include selection ofeither normal or automatic modes;switch-controlled AC-DC coupling;provision for external triggeringsignals. The sweep may be triggeredat any point along the positive ornegative slope of the input signal.For More Details Circle (72) on Reply Card

Automatic LoggingMcBee Laboratories will intro

duce their Automatic Digital Logging System. Digital systems offerthe advantage of absolute readings,not subject to visual interpretationand with accuracies up to IO timesthat of comparable analog data. Anautomatic digital logging systemcan therefore perform this necessary function faster and with ahigher degree of accuracy thanpreviously thought possible.

The V 11/21 Auto matic DigitalLogging System was designed forthis purpose and is a complete, selfcontained system, including theprinter. The VI 1/21 AutomaticDigital Logging System displaysand prints, date identification, timeChannel number and data, such asvolts, amps, watts, etc. The date isentered initially by pushbuttonswitches on the front panel. Basically, a digital logging system willsample, measure, digitize, displayand record (in digital form) the analog inputs from single or multiplesources. In addition, the Vll/21Automatic Digital Logging System




incorporates a real time solid state,24 hour digital clock, the time ofwhich can be both visually displayed and printed out.

Utilization of reliable, solid-stateintegrated circuit logic resulted in acompact design. Only 7 incheshigh. Maintenance requirementsare at a minimum by using easilyaccessible plug-in printed circuitcards which promote modern servicing techniques. In addition tothe benefits of low maintenancerequirements, wider and more versatile applications are made possible through plug-in complement a r y optional elements andequipment.For More Details Circle (73) on Reply Card

Magnetic FilmA new line of acetate-base mag

netic recording films, featuring animproved high-output, low-noiseoxide coating, has been introduced,by 3M Company, St. Paul, Minn.According to 3M, the improved

oxide coating gives the film a wide

dynamic range with the samehigh-output and low noise characteristics of the polyester-basedScotch types 340 and 341. The newline also features better resistanceto wear and scratching thanacetate-based films previouslyavailable from 3M. The acetatebacking facilitates edge numberingand editorial markings.The new films are available in

full coat, stripe coat and clear edgeconfigurations for 35mm and fullcoat for 16mm.

Scotch brand 337 full-coat magnetic film is intended for the mostcritical original recording andmixing applications.

Scotch 338 stripe-coat film features a 300-mil wide coating justinside the sprocket holes on oneside and a "balance stripe" justinside the opposite sprockets. Bothedges and the center of the film areclear to simplify synchronizationwith pictures or writing or editingdirections.

Scotch 339 clear-edge magnetic(Continued on page 58)

I----~7: I~ ··•·:•_. , .. ..!.. ·- ~

IPSTHE MDA· 1B IS A SELF-CON·TAINED RACK MOUNT, ORTABLE TOP UNIT, INTENDEDTO SUPPLY DRIVE MOTOR

POWER TO PROFESSIONALTAPE DECKS FOR THE@PURPOSE OF VARYING TAPE SPEEDUNDER PRECISECONTROL.

f/MULTISYNC MDA-18FEATURES<: WIDE F!lEQUENCY RANGE •:8 J.:.¡ Hz·:· VERNIER CONTROL FOR FINE PITCH ADJUSTMENT.;. NO MODJFICATIQNS OF RECORDER REQUIRED<·FIXED 120 Hz FOR 30 IPS OPERATION.·• FAIL-SAFE 1\MPUFIER PROTECTION CIRCUITRY-:·EASILY PATCHED FROM RECORDER TO RECORDER-'.:QUADRATURE ORIVE FROM DUAL AMPLIFIERS

AND 90 DEGREE OSCILLATORS

1\PPLICA TIONS"PHASING-DELAY" EFFECTS

-:· TUNE TRACKS FOR RECORDING N01':- TUNEA BLEINSTRUMENTSJO IPS DRIVE FOR 7 5 15 IPS RECORDERS

-'· COMPENSA TE FOR OFF-SPEED TAPES.·. VARIABLE-DELA Y FOR DOUBLE-TRACKING-·- LENGTHEN SHORTEN RUNNING TIME OF BROAD

CAST TAPES

THE MDA-1 B CONTAINS ITS OWN POWER SUPPLIES, OSCILLATORS, AND POWER AMPLIFIERS. THE CONNECTIONS TO AND FROM A DECK ARE MADE SY TWO CONTROL (ASLES. THESE CAN SE INSERTED INTOEXISTJNG CONNECTORS WITHOUT ANY MODIFICATION TO THE TAPE DECK.

PACIFIC RECORDERS AND ENGINEERING CORPORATION "11760 SORRENTOVALLEYRD., SH DIEGO, CALIFORNIA 92121TELEPHONE(714) 453-3255

July, 1973For More Details Circle (44) on Reply Card

o000HH8!•·. 'RUSS~.os

:THE ONE.tFOR '<9.U!

We just feel like singing about RUSSCO'sNew STUDIO/ MASTER 505 Audio-Mixer- LOOK! 5 mixing channels, 4 channelswith built-in Preamps! Each adjustablefor mic, phone or hi-level! Channel 5 has5 hi-level push-button balanced inputs!Built-in Monitor Amp, cue-speaker, headset amplifier! Push-button key switchingwith LED indicators! Allen-Bradley MadPots! FET monitor muting and much more!Available in attractive cabinet or as arack mount (in 5 Y2" space) model. Modcolors - maroon & black face, blue-greycabinet! PRICES THAT START AT UNDER$500 I! I


Yau get the most "headroom" for the money(+18 DBM) with RUSSCO's New "FIDELITYPRO" and "FIDELITY-MASTER" phone preamps. 8 models stereo or mono to fit yourneeds, self-powered and featuring a unique"easy-service" case. Years ahead in engineering with economical prices starting al $92.00


ELECTRONICS INCORPORATED1070 Brookhaven, Clovis, Calif. 93612

Phone (209) 299-2167

57



UP TO65 X

SAVINGSPlus performance !hat is creatingexcitement in Engineers around thecountry! "Fantastic sound" ... "VeryClean" "Superb! ... Send twomore "

Proof? Our standard 1O day evaluation period lets you see and hearthe performance and the full service, 2 year warranty demonstratesthe reliability.

Place your order today. Then prepare yourself for a very satisfyingexperience'

TURNTABLEPREAMPLIFIERS

MP·B (Mono) $60SP·S (Stereo)$90

Outstanding sensitivity and near perfect reproduction. RIAA/NAB equalized -0.5 mv sensitivity @ 1 KHzfor -L4 dbm out - Balanced 600ohm out - minus 65 db S/N ratio -+20 dbm out max - =1 db freq.response - Internal power supply- Table top/bracket mount. Shipping weight. 31;, lbs.

MIC/LINE AMPS

MLA • 1 (Mono) $68MLA • 2 (Dual) S96

Dual function utility amp. Inputs formic and/or line - 600 ohm balanced outputs - mic input, -65 dbfor +4 dbm out - +20 dbm outmax. - =0.5 db response, 1O Hz-20Khz - 0.1% or less dist. - Internalpower supply - Tabletop/bracketmount. MLA-2, Stereo/Dual Mono.MLA-1, Mono. Shipping weight, 4 lbs.

•

DISTRIBUTION AMP

6 BALANCED OUT~DA· 6 S95

One third the cost of comparableunits. Six 600 ohm balanced outputs- Balanced bridging input - 26 dbgain - +20 dbm out max. - Inputlevel control - 0.1% or less dist. -=0.5 db response, 1O Hz-20 Khz -Internal power supply - Tabletop/bracket mount - Shipping weight,4 lbs.

~~

TAPE CARTRIDGE\ ' ~ADER (AUTOMATIC)

"11"-~-----· ACL • 25 S159

Precision winding without guesswork. Dial in the minute and/or seconds desired, throw switch to run.That's it! The exact amount of tapeis fed onto the cartridge hub to thesecond, and shuts off automatically.No waiting around, no guessworkand 1 sec. accuracy. Also has exclusive torsion control for propertape pack and winding of variouscart hub sizes. TTL digital controlcircuitry. Shipping weight, 30 lbs .

.~~

RAMKO RESEARCH2552 "E" Albatross/ P.O. Box 6031

Sacramento, Calif. 95860 ( 916) 489-6695


~~IPRODUCTS(Continued from page 57)

film specifically is intended formultiple track re-recording. It isfully coated except for each edgefor easier viewing of edge numbers.For More Details Circle (74) on Reply Card

Automatic CounterMonsanto has developed a new

32MHz Automatic Counter, themodel l 50A, to add to its extensiveline of digital counter-timers, frequency generators, voltmeters,

data acquisition components anddata acquisition systems. The newmodel 150A features a countingrange from 5Hz to 32MHz, acrystal controlled clock, 5 digitlong-life LED display, and automatic ranging for full resolution.Decimal points are automaticallypositioned as is the display of unitsof measurement and non-significant zeros are automaticallyblanked.

Able to operate on standard lineAC or from an optional batterypack, the model I50A has a built-intest position and an overrange indicator in the manual mode.For More Details Circle (75) on Reply Card

Stereo and SCAMonitors

McMartin Industries, Inc., offerstwo new FCC type approved unitsfor monitoring all parameters relating to stereo and SCA multiplexoperating modes; the TBM-2200AStereo Modulation/Pilot Frequencyand the TBM-2000B SCA Modulation/Frequency Monitors. Thenewest generation models incorporate the latest in electronic, packaging. and function designs.The TBM-2200A stereo unit may

be driven by the new McMartinTBM-3700 FM Frequency/Modulation Monitor or by the previouslyavailable, TBM-3500A or TBM-4000A models. In addition tosimultaneous metering of left andright channel modulation, theTBM-2200A features continuousmonitoring of the 19 kHt pilot frequency deviation. The modulationmeters serve a secondary functionof measuring channel separation,crosstalk, 38 kHz suppression andindividual channel stereo signal-tonoise ratios. Internal calibration of

··y·:...,.=-. -::::..1............

.r:.

pilot injection level and frequency isfeatured.

The TBM-2000B SCA modulation and frequency model may beused with the new TBM-3700 baseband monitor or with the previousMcMartin TBM-3500A, TBM-4000A or TBM-4500 A models. TheTBM-2000B monitors all SCAtransmission characteristics; injection level, modulation, SCA carrier frequency, and SCA FM signalto-noise and crosstalk. Internalpush-button calibration of the frequency meter, injection level andmodulation meter insure rapid andprecise maintenance of the monitoring functions.

Crosstalk levels between mainand subchannels or between subchannels as well as the inherent FMsignal-to-noise level of the monitorcan be measured. The TBM-2000Bis available for standard 41 or 67kHz operation and for other subcha nnel frequencies by specialorder.For More Details Circle (76) on Reply Card




For further Information, circle dataIdentification number on reader service card.

112. HEATH/SCHLUMBERGERSCIENTIFIC INST.-This 52-pagecatalog provides detailed descriptions and specifications for thecomplete Heath/Schlumberger lineof design and lab instrumentation.Included in the catalog is a newseries of VHF counters that canprovide capability to 600 MHz foras little as $795 ... a complete line

114. INTERNAT'L GOOD MUSIC, INC.-New illustrated literature on the complete line of IGMaudio control systems is now avail-

r.-----==111frUSEOURCAS~IlllFORYOUR NEWiiiIll EQUIPMENT IllIll You choose the equip- Ill

ment; we will lease it toIll you.-3-4 or 5 years with Ill

option to buy.Ill Broadcast Equipment IllIll Leasing Co. IllIll

DIVISIONº. F ANCHO.R .LEASING CORP. IllGrant Building

Pittsburgh, Pa. 15219Il Area Code 412-281-3768 JJIlli= - - - - - ==4!JFor More Details Circle (53) on Reply Card


FREE CATALOGHARD-TO-FIND PRECISION TOOLSLists more than 1700 items-pliers,

~~l~~ze:;~l;,ir~~t~~~Í~~i~~~~~~~~fe~¡~~and cases. Al so includes four pages ofuseful "Too! Tips" to aid in tool selection.

l.!lrr;~aFor More Details Circle (52) on Reply CardJuly, 1973

able. A four-page brochure describes the IGM 400, an economical, prepackaged six-channel audiocontrol unit, which schedules alltalk features on a real-time basiswith music automatically filling inthe balance of the time. IGM's 500system, detailed in a six-page brochure, is also of time-insertiontype, but can handle any number ofinputs and is expandable to includepeg clock, music sequencer, realtime switcher, random selectmemory and automatic programlogger. An eight-page brochuredescribes IG M's computerized 700control systems. Seven models,each with built-in software, provide a wide range of memory capacity and operating features. Allare sequentially programmable,with real time capability, arereadily expandable and are compatible with automated traffic, accounting and billing systems.

115. INTERNA T'L. RECTIFIERCORP.-Three new series of 1.6amp SCRs in T0-5 cans are described in a data sheet from theSemiconductor Division of Internat'l. Rectifier. The types, whichprovide an additional source forunits previously on the market, further expand IR's line of low powerSCRs. The series, IR5, 2N2322,and 2N4212, are available in versions with rated voltages of 25 to400 Volts. The new units have sensitive gates and require only 200microamps maximum gate currentto trigger at 25ºC. Included in theliterature are eight graphs, a dimensioned outline drawing and a photograph of the devices. Completeratings and specifications are provided. Applications include controlof fractional horsepower motors,drivers for computer readouts,timers for industrial process control, shift registers, and switchesfor such devices as burglar alarms.

uniqueballpointdrives hex socket screws

trom any angleEver try to drive hex socket screws from anodd angle? Want an easier, faster way to drive'em under any conditions?HERE'S YOUR ANSWER: With unique "ball·point", you can slip these Xcelite screwdriversinto hex sockets ... slick as a whistle andsecure as a vise . . straight-on or from anyangle ... to drive 'em home in a flash! 9 sizes:.050" · 3/16". With fixed handles, singly orcomplete set in roll up kit, and as inter·changeable Series 99 blades, singly or withhandle and extension in compact case.

REQUEST BULLETIN 273l

118 Bank Street. Orchard Park, N.Y. 14127In Canada contact Charles W. Pointon, Ltd.


NOW WHEN YOUTHINK SMALL ... THINK

Xcelite Minidriver sets

.~~

Smaller than a matchstick, Xcelite's "Mini·Screwdrivers" put product precision in yourhands for fine work. Technicians, servicemen,assemblers, model-makers, hobbyists welcomethese color-coded little screwdriving gems.Instruments, apparatus, machinery, optics,cameras, watches, clocks .. useful whereverscrews as tiny as 0000 are involved.Two handy kits in see-thru plastic cases:MSO-five drivers for slotted screws, tipsfrom .040" to .100". M60-same plus 00Phillips driver and piggyback torque-amplitier handle.REQUEST GENERAL CATALOG 171

nationwide availabilitythrough localdistributors

118 Bank Street, Orchard Park, N.Y. 14127In Canada contact Charles W. Pointon, Ltd.




ROJ..I rlqhtfrom the startModular Audio Series 200

Roh has a quality line you can startwith ... and stay with. Buy a singlemodule or several now. Then build anequity in fine audio equipment:modules, enclosures and accessories.Write for '73 catalog.

210 10 Watt Power Amplifier$60.00

212 1x5 DA with TransformerOutputs $110.00

214 Microphone/Line Preamplifier$75.00

216 4 Channel LOR Attenuator/Switch $60.00

~~-.•~':4Jfr·~·.• ~ ~~~'*'-';.~~:e---~:,~

•.••.•• ,>.•••~ .••••,,.•••• ¡ i' .·

218 Dual Channel Phono/TapePreamplifier $75.00

220 Dual 10 Watt/Single 30 WattPower Amplifier $110.00


Roh Corporation150 Technology Park/Atlanta Suite 15

Norcross. Georgia 30071 Ph: 404/449-0873 120. PHILIPS-A four-page full


117.KAPPA NETWORKS, INC.-A new brochure provides basicspecifications on their standard andcustom design LC filters. Fullspecifications are given for the dualin-line (DIP) filter series whichoffers cutoff frequencies up to 20MHz. Additionally, photos andbasic specifications are shown forthese filter products: low pass,band pass, high pass, band reject,matched phase and attenuation,maximum flat delay, linear groupdelay, and group delay and attenuation equalizer networks. Specifications and a series of curves describing Kappa's constant groupdelay filters are included.118. K-TECH, INC.-Burn-in

and electrical test sockets andcarrier/contactor systems for semiconductor devices are described bythis six-page two-color brochure.Parts are divided by type ofpackage to be socketed. Information and specifications for insulating and contact materials are included. Instructions for estimatingsocket and tooling costs for customracks are also featured.119. MAGNAVOX CO.-New

literature by Magnavox includestwo revised catalog pages; one onindoor directional couplers and oneon indoor splitters. Both revisionsspell out improvements in performance specifications with particularrespect to tap-to-output isolationand maximum insertion losses.Products described on the indoordirectional coupler page are SeriesI800M, Broadband CornerMolding Couplers; Series 600B,Broadband Sub-Miniature Couplers; and Series 765B, BroadbandWallplate Couplers. Describedwithin the indoor splitter page areModel ML-2, Miniature TwoOutput Splitter; Model 4022, SubM iniature Two-Output Splitter;and Series 90, Hybrid Splitters intwo, three, four and eight outputversions.

color brochure describing thePhilips PM3400 1.7 GHz dual tracesampling oscilloscope is now available. The brochure describes thefeatures and applications of thePM3400, which offers calibratedsensitivity of 1mV/cm at 1.7 GHz,30 nanoseconds delay in both channels, and stable triggering onamplitude-modulated carriers to1.7 GHz. It also points out how theP39 long-persistence phosphor andthe instrument's capability for continuously variable sampling ratecombine to eliminate flicker evenat extremely low signal frequencies. The PM3400 is availablethrough Test & Measuring Instruments I ne., of Hicksville, NewYork.

121. RAYTHEON CO.-Newliterature offered by RaytheonCompany's Special MicrowaveDevices Operation describes thecompany's line of Micro State lownoise, high efficiency gallium arsenide avalanche diodes. Rangingfrom 4 to 40 gigahertz and from 20milliwatts to more than 4 Watts,the line of 39 impact transit time(IMPATT) diodes is offered in sixdifferent package configurations.

122. RCA-Performance andoperating details on the TK-630 arecovered in a new, amply illustrated16-page brochure. As a broadcastcolor camera for studio or field use,or for educational and closed circuit applications, the TK-630Camera provides quality performance at moderate cost. A two-pieceunit with detachable, plug-in viewfinder, the camera is readily portable, easy to set up and operate .Picture fidelity is excellent. Thecamera uses three I-inch lead oxidepickup tubes, and incorporatesmany of the quality features ofpremium priced cameras, includinga sealed prism optical systemmounted on a rigid metal bedplate.

123. RHG ELECTRONICSLABS., INC.-A new one-pagecatalog sheet describing their Hybrid IC Preamplifiers for use inmicrowave receiving systems andmonopulse and phased array radars, is now available. The company designs and builds microwave, RF, and IF components,




receivers and transmitters. Thesheet describes and illustrates fixedgain, variable gain and high powermodels featuring low noise andsmall size. Price reductions from$125 to $95 on two specific fixedgain models are also noted. General information on size, weight,and special options are included.

124. ROHDE & SCHWARZThe 1973 Rohde & Schwarz measuring instruments catalog is nowavailable. The 232 informationpacked pages provide a completetechnical guide of the comprehensive Rohde & Schwarz productionprogram. The instrumentationcovered includes, power, sweep,noise, AM/FM-synthesized andprogrammable signal generators;precision terminations, fixed-variable and programmable attenuators; wave analyzers and selectivemicrovoltmeters; freid strengthmeters; spectrum analyzers; wideband microvoltmeters and powermeters; impedance and reflectionmeasuring equipment; R, L, C andQ meters; diode, transistor and lCtesters; TV measuring equipment;sound level meters.125. ROUNDTABLE, INC.-A

new catalog covering over 50 filmsand dozens of training aids is nowavailable. The 1973 catalog will beuseful to trainers and teachers inbusiness, manufacturing, government, and public education organizations. Roundtable produces anddistributes films on Business Management, Communications, Sales,Vocational Education, Supervision, and Business Skills Development.

126. HOWARD W. SAMS &CO., INC.-A new 1973 SamsBooks catalog is now available.The 84-page book gives an alphabetical index and numerical index.Some of the topics covered areamateur radio; appliances; motors;power mechanics; audio & hi-fi;basic & hobbyist; cb & communications; circuits & components;data processing; and many others.Also included is information onSams Photofact.

127. SCOTT BUTTNER-Twofour-page bulletins are now available. Bulletin Number 400-1 describes the SBC-400 Voice-Over-

July, 1973

Video Subcarrier Multiplex. lt isillustrated and gives specifications.Bulletin Number 502-1 describesthe SBC 502 Wide Band Multiplex.lt is fully illustrated and also givesspecifications.128. TABER MFG. AND ENGI

NEERING CO.-A new bulletindescribes Taber's new audio headsfor direct replacement in Ampexand Scully equipment. It also describes precision lapping of Ampexand Scully audio heads and customaudio heads.

129.TELEDYNE PHILBRICKThe Linear Short Form Catalog, aguide to all of Philbrick's latestdevelopments in analog technologyis now available. Specially featuredis Philbrick's 1421 series ofeconomy FET microcircuit opamps, the 1421, 1422, 1424, 1425,1426, 1428 and 1429. They offer abroad range of electrical specifications to meet the exact requiremen ts of specific applications withstandard, off-the-shelf products.Another exciting new microcircuit


Here in one compact and informative24 page booklet is all the data you ·need to select a Precision Audio andRFAttenuator for your application.Reference Charts, Circuit Diagrams,Types and Uses, Current and VoltageRatio Tables, Ratings, Etc., make this ahandy and invaluable reference.

SEND FDR YOUR FREE COPY TODAY.

TECH LABS, INC.Bergen & Edsall Blvds.Palisades Park, N.J. 07650Tel.: (201) 944-2221


ATTENTION ENGINEERS:EQUIP YOUR STATION WITH A

Complete Remote PackagePackage includes:* Model 289 AC/DC Microphone Line Driver w/Built-in Voice Coupler by

PDMC* The New Sportscaster Headset - Combination of finest professional micro

phone and high-performance headphone by Telex.

* Fully warranted for one year against defects in Parts, Materials and Workmanship.

* Satisfaction guaranteed. Money back if not satisfied with units after 15 daytrial.

OnlyCompleteSpecs

AvailableOn Request

Complete

ENCLOSE CHECK WITH ORDER OR PHONE:

PULSE DYNAMICS MANUFACTURING CORP.Colchester, Illinois 62326Ph.: AC 309/776-4544ATTN: SALES MANAGER

~

\f.::IFor More Details Circle (43) on Reply Card

61




is our new Model 1324 fast-settlingmonolithic op-amp which offersguaranteed specification to accurately resolve high-speed data.Completing the list of new products are the 1028, 1029, 1030, 1702and 1703 discrete op-amps and the1423and 1427 microcircuit units. A

Broadcasters' Choice:

------ - - -- ---~·-·• --~--,•.,- - .

Spotmaster /RevoxA77 Mark ffi-B

• Lifetime guarantee• Takes 1OW' reels & NAB hubs• Standard & Dolby versions• Superb specs & performanceSpotmaster and Revox have joined forcesto develop this ruggedized, rack-mountedversion of the A77 stereo recorder specifically for broadcast use. Choose the standardversion, or the Dolby model with its in·credible 70 dB S/N ratio. All basic partsexcept heads, capstan and pressure rollerare guaranteed for life. Your choice of 2-or 4-track stereo operation at 7-1/2 and3-3/4 ips. Other speeds, full-track heads,accessories optional. Call or write:

BROADCAST ELECTRONICS, INC.---A Filmways Company---8810Brookville Rd.,Silver Spring, Md. 20910

(301) 588-4983 • TWX 710-825-0432

section on nonlinear function modules and low-cost modular powersupplies completes the productdescriptions.

130. TERRACOM DIVISIONConic Corp. A new four-page brochure describing the series TCM-6Microwave radio has just beenpublished. The TCM-6 is a frequency agile radio operating in the1.7 to 15.25 GHz range and may beeither fixed tuned or knob tunedacross each band with frequencyreferenced to plug-in crystals for0.005 percent stability. Both thetransmitter and receiver are portable and may be tripod or fixedrack mounted. The brochure contains complete specifications andapplications information.

132. WESTINGHOUSE ELECTRIC CORP.-A new brochuredescribes most of the many different phosphors which can besupplied in the cathode-ray tubesmade by the Westinghouse Electronic Tube Division. The 32-pagepublication helps buyers select aCRT with the optimum phosphorto meet any of a wide variety ofapplication requirements. Spectraland persistence characteristics andtypical applications are given forover 50 standard and special phosphors. A brief explanation of theuse of phosphors in CRT screensand glossaries of terms and symbols are included.

Digital Logic(Continued from page 38)

viously. For the first state, one seesthat with all inputs low and Cinhigh, the L1 output is high.Realizing that a carry bit is addedto the least significant bit, thisindicates that A1, B1 and :L1 arethe least significant bits of thenumbers added and the resultingoutput. This then implies that A2,82 and :L2 are the most significantbits of this 2 bit full adder.

Consider now Row 6 of the tablewith Cin = l. We are adding thetwo numbers 11 and 00 with acarry input of 1. The expectedoutput would then be 00 with acarry output. This agrees with theentries for the output in the truthtable. Similarity any state of inputconditions can be analyzed todetermine the expected outputstate.

Studying manufacturers's datasheets is a very good way to learnabout digital IC's. All of theconcepts discussed in this articlecan be studied in detail in anymanufacturers' data book and atthe same time a knowledge of realworld device numbers, pin arrangements, and switching parameterssuch as rise, fall, and delay timescan be obtained.As supplemental reading in this

area, the book HANDBOOK OFLOGIC CIRCUITS* BY John D.Lenk presents a practical and easyto read study of many of thecircuits in use today. D*Restan Publishing Company, Inc. 1972

131. TRIPLETT CORP.-A new28-page catalog featuring manystandard type panel meters andaccessories plus a customizedpanel meter service, all for use inindustrial process control, electronic instrumentation, communications equipment, military groundsupport equipment, computer anddata processing systems, laboratory and educational applications,is now available. Many new panelinstrument additions are containedin the comprehensive, two-colorcatalog which is three-holepunched for ring binder referenceusage. To make it easy and quickto order, user net prices are provided for all panel instrumentslisted in the new catalog. Also,complete electrical specificationsand dimensional drawings of thepanel instruments and their mountings are given.

MONAURALSTEREO

SCA

•receiversTBM-10008 series

plug-in stereo, seaand narrow band options

single channel tor»FM broadcast, 1SOMHz,

VHF-TV aural~:¡=- •

-==-five channel torFM broadcast

prices from S250•

MCMartin McMartin Industries Inc., 4500 South Seventy-sixth StreetOmaha. Nebraska 68127 Phone (402) 331-2000 Telex 048-485For More Details Circle (50) on Reply Card




PllFESSlllAl ~~-~VII JAMU

CONSULTING RADIO ENGINEERSAppllc•tlon1 •• d Field En9lnHrln9

)45 Color•do livd.,hone: IAru Code JOJI JH-5562

DENVER, COLORADO 80206Member AFCCE

SMITH and POWSTENKO

Broadcasting and TelecommunicationsConsultants

2000 N Street, N.W.Washin~on, ne. 20036

(2 2) 293-7742

CAMHIDGE CRYSTALSPRECISION FREQUENCYMEASURING SHYICE

SPECIALISTS FOR AM-FM-TV445 Coftcord Ave. ,hone 176-2' IO

C•mbrld11e. M•u. 021 JI

RALPH E. EVANS ASSOCIATESCon1ultln9 R•dlo En9inHrsAM . FM. TV. CATV. ITFS1500 North Sherm•n Blvd.

MILWAUKEE, WISCONSIN 53216,hone: 414-442-4210

CHU ASSOCIATES, INC.Telecommunications Division

AM-FM-TV-CATVApplications- Facilities Planning

Field Surveysand ProofsAppraisals

800 FeslerSt., El Cajon,Ca.92020(714) 442·9459

TWX 910 331 1178

SESCO, Inc.47 NICHOLS AVENUE

P. O. BOX 518

(206) 378-2137

FRIDAY HARBOR,WASHINGTON, 98250

Moving?Send Your Change

Of Address To:Broadcast Engineering

1014 Wyandotte


July, 1973

Advcn ising rates in Ciassilicd Section arc 15¢ perword. each insertion. and must be acct. 11¡. nicd bycash to insure publication.

Each initial or abbreviation counts a full word.Upper case words. JOc each.

Minimum classified charge. $2.00.

For ads on which replies arc sent to us forforwarding. there is an additional charge of $2.00to cover department number. etc .. which is printedin advertising copy. and processing of replies.

Clasvificd column' arc not open to advertising ofany products regularly produced by manufacturersunless used and no longer owned by themanufacturer or a distributor.

TRAININGPASS FCC EXAMS with Ameco books. Each bookcontains FCC questions plus simplified answersplus FCC-type exams and answers. 3rd class 75c.2nd class $2.25. I st class $I .50. Free catalog.Amcco Publishing. Ji4G Hillside Ave .. WillistonPark. N.Y. 115%. 8-72-tf

FIRST PHONE thrnugh tape recorded lessons athome plus one wcc k pe rxo n a l instruction inWa,hington. DC. Atlanta. Boston. Detroit: NewOrleans. Minneapolis. Seattle. Denver. Portland.l.ov J\ngek v. Proven results. Our 17th yearll';u:hing FCC license courses. Bob Johnson RadioLiccuvc Preparation. 10600 Duncan. ManhuttunHcadi. Calif. 80266. Phone 21.\..17<J-4461. 1-69-tf

PASS FCC lirsl and second clas ..•exams with new21 lcvxun. 450-page courxc. Starts with basicclcvuicit y. Over h(XJ FCC-type. multiple-choicequest iou-, and sample exams im..:luclcd. No previoust cchnicnl knowil'dgl' required. Commercial RadioOperator Theory Courvc . #I S-01. Only $5.<JS.A111n·o Publishing. J14G Hillvidc J\ve .. WillistonPark. N.Y. 115%. 8-72-tf

EARN ELECTRONICS DEGREE, mainly bycorrcvpoudc ucc . F.C.C. license preparation ineluded al your option. Accredited hy AccreditingCon1111is~ion of NHSC. G.I. Bill approved. Freehroch urc. Write: Dean. Grantham School ofEngineering. 1505 N. Wcvtcru. Hollywood. California 'XXJ27. 8- 72·tf

FCC RADIO TELEPHONE OPERATORSLICENSE in six weeks. Classes (day & evening) inAtlanta. Dallas. Denver. Ft. Worth, Hartford,Houston. Memphis, Nashville, New Orleans,Oklahoma City. and San Antonio. For informationcontact Elkins Institute. 2727 Inwood Road,Dallas, Texas 75235. 214-357-4001. 5-73-tf

SERVICESCRYSTAL & MONITOR SERVICE. Frequencychan g c , repair or replacement of oven typebroudcus t crystals. Also frequency change andrccalibrm iun or repair of AM frequency monitors.and f-1.p FM ruouit orv. Fast service at rcasonublcpriccv. JO ycarx experience! Call or write: Eidsonllcctronic Co. Box %. Temple. Tx. 76501. Pho.817 77.l-.lCJOI. <J-70-tf

CAHTRIOGES SPOTLESSLY CLEANED,REBUILT AND HE LOADED with Scotch lfi7.Like new al approximately half price. Also,BEST PRICES anywhere on new FIDELIPACearls, :·1M professional Lape and other studiosupplies. YOUR OIWER IS YOUR CHARCEACCOUNT' Full guarantee. FREE CATALOGUE. Lauderdale Electronic Labs, lfi S.W.I:1th Street, Ft. Lauderdale, Fl·a. :1~:11!í r~O!íJ!í2éi-0478 4-78-fil

WANTEDWANTED: All s ur p lus b r o a d cn s t c q ui prn c ntcspccially clean A.M. & F.M. t r a n sm it te rs .contrucrors. capacitors. Surpluss Equipment Sales.2 Thomcliffc Pk. Dr. Unit 28 Toronto 17. Ont;Canada. I· 7J-tf

TUBES WANTED-All types-CeCo 2115 AvenueX. Brooklyn. N. Y. 11235, 212-646-6300-Anytime.

7-73-l 2X

EQUIPMENT FOR SALE

SURPLUS AUDIO PATCH PANELS. All Standard Conligurations. Gulf Telephone & Electronics.Inc .. P.O.Box 42130. Houston. Texas 77042. 7-72-tf

MOTORS FOR SPOTMASTERSNEW Paps hysrcrcsix synchronous motor HSZ20.50-4·470[) as used in series 400 and 500111;11.:hine\. Price $39.00 cach prepaid, while theylavt , {X} day wu rrnnty. Terms check with orderonly. no COIJ's. Not recommended for Tnpccustcr'nic' h(X) or 7!Xl.

TAl'FCASTER TCM. INC.. Box óh2.Rockvil!c. Maryland 20851

1-72-TF

- - - - ------------"NEW & USED TOWERS, Buy. Sell or Trade.Freet. Ground wire 8Sc lh. Bill Angle. <Jl<J-752-.1040. Hox SS. Greenville. N.C. 27834... 2- 71-tf

ONE STOP for all your professional audiorequirements. Bottom line oriented. F. T. C.Brewer Curnpn ny. P.O. Box 8057, Pensacola.Florida .12SOS. 7-71-tf

QUALITY AUDIO CONSOLES arc uu r xpccialty.Moderu -.tyling with slide potentiometers and"-.oft" audio -.wi1d1ing. We manufacture 8 standurd n1ns11k-. at very compct it ivc prices. However.Wl"ll mun u In ct u rc a c u vt urn vys t e m to yourvpcvifu-at iou-, if you prefer. Also plug-in audiomod ulcv including distr ihut ion amplifiers. pre.uuplificrv. monitor .uuplificrv. etc Wrill' or phonefor prking and vpccific.u ious. SYSTEMS EN·GINEERING COMAPNY, l'.0. Box 49224. At·l:1111a.Ga .. 10.12'1. 404-482· 2446. 2-73-1 2x

- - - ---· --------------HELIAX-STYROFLEX. Large stock-bargainprilT-.-te ...•tcd ;111c\ ccrt ilicd. Write for price and-.111rk \i,t'\. Sierra Western Electric. Box 23872.Oak land. Cali I'. 94h2.l. Telephone (41 SI 832-3527.

¡. 73-tf

PORTABLE B&W PRODUCTION UNIT with2-Ampex 327 Studio viewfinder cameras withtripods and heads. I -Sylvania camera for effects.J.¡¡·· monitors. 5 channel audio mixer. videoswitcher/fader, special effects unit, 2-1 sync, inter·com (all equipment mounted in portable console).l-EIAJ-1 V.T.R. with 19 .. rcciever, mikes, cables.lens. etc. $3350. Thomas Gilchrist 316-722-5116.

7-7-lt

RECORDING STUDIO CONSOLEIdeal for sophisticated TV audio. 18 microphone or high-level inputs with EQ & echo oneach. EQ on each of the 4 output channels.Built-in multi-freq. oscillator. Group submastering; channel masters; grand master. 4reverb devices. 4 dual-60 watt amps. Intercomwhile recording; talkback (rnic's. included).Audition any input while recording. "Silence"button prevents performer ruining audio bydisturbance during echo "overhang" at end of"take". Producer's desk; all audio in accompanying rack. Very compact! Slightly used,guaranteed. Sacrifice for half of new value.

Soun DesignBox 291, Beverly Hills, Calif. 90213

63



EQUIPMENT FOR SALE CONT.

SURPLUS MICA AND VACUUM TRANSMITTING CAPACITORS. Large stock; immediatedelivery. Price lists on request. SURCOMASSOCIATES. 1147 Venice Blvd., Los Angeles,Ca. 90015 (213) 382-6985. 5-73-12t

STEREO CONSOLE, stereo limiter. stereo cartrcc/pb. turntables w/arms and carts. misc. items.1-817- 723-6688. KNTO. 3700 Onaway Trail.Wichita Falls. Texas 76309. 6-73-2t

PARTS - for SPOTMASTER & TAPECASTERcartridge units. IN STOCK - IMMEDIATEDELIVERY over night to Pennsylvania, New York,& New Jersey. Pressure rollers for all machines.LOW PRICES. some used parts in stock.COMMUNICATION MEDIAS, Box 54. Allentown. PA. 18105 215-437-0607 or 437-9447. 6-73-2t

BUILD YOUR OWN TV AND RADIO PRODUCTION EQUIPMENT. Easy. inexpensive.(mos t lv !CL Plans or kits: Special EffectsG1..·111..T;1tor.Automatic Logger. Vertical IntervalVideo Switcher. Solid S1a1e Lighting Board. PresetAudio- Video Board. Preset Lighting Board. CrystalControlled Wireless Mikes with matching receivers.Subsonic Tone Control for audio tapes. 8MM SOFCamcrus and Projectors, Distribution Amplifiers(Svn c. Video. Audio). Audio Control Boards(Studio 8.: Remote) Proc-Amp with compensationand rcgcncr.n ion for adapting Helical Scan VTR's10 brondcuxt standards. PLUS specialized correvpundc ncc cou rs cs in Telephone Engineering(S.Jll.50). and lntcgratcd Circuit Engineering ($49.50). Plans from S:'-.95 to SIS. SUPER CATALOGplus years updutcing of new devices Air MailedSI .OO. Don Britton Enterprises. PO Drawer G.Waikiki. Ha. 96815. 4-73-12t

FIDELIPAC CARTRIDGES, Type A. used. assorted lengths. Over 700 in all. Open to offers,cash or equipment. Okanagan Broadcasters Ltd..P.O. Box 100. Kelowna. B.C. Ph. 604-762-3331.

7-73-2t

CARTRIDGES-65 cents each. Used Fidelipacs invarious lengths and excellent condition. Minimumorder-25. Send check or money order to Kartco,Box 291. Route #1. Stone Ridge. N.Y. 12484.Telephone (914) 687-9355. 7-73-3t

SITUATIONS WANTED

ENGINEERING STUDENT, !st phone. maint ainnnce background. production experience, seekssummer position possibly permanent. Bill Motley,1212 S. Charlotte Ave.. San Gabriel. California91776 7-73-lt

HELP WANTED

AN OPENING exists for a mobile technician inthe Detroit area. Experience in maintaining andoperating VR 3000 and color carneras in the fieldis a prime requisite. Extensive travel may benecessary. Resumes and inquiries should bemade lo Edite! Productions Incorporated, 24151Telegraph Road. Southfield. Michigan 48075 orcall: 313-35:1-1660. 4-73-4t

CONSIDER THE MERITS of using a respectedemployment service; both employer and employeeshave successfully used our service over the past 8years. We lill all engineering openings at radio,television stations and cable systems. People arethe real competitive difference. Employers, securethe finest people in broadcasting and cable.Employees. move up with AMPS. Send us yourresume now. The AMPS Agency, 11661 SanVicente Blvd. Suite 300. Los Angeles, California90049. (213) 820-2678. 5-73-tf

EDUCATIONAL NETWORK seeks experiencedtransmitter supervisor for transmitter site. Sendresume. salary requirements and availability to:Director of Engineering. Iowa Educational Broadcasting Network. P.O. Box 1758. Des Moines, Iowa50306 7-73-lt.

64

HELP WANTED CONT.

CHIEF ENGINEER for like new non-directionalAM and automated FM. Southwest resort area.Full maintenance. Light air watch. Excellent working conditions. Medium-small market. LocalOwnership. $800.00 per month start. Successfuloperation. Write Box: 284 Broadcast Engineering.1014 Wyandotte St .. Kansas City. Mo. 64105.

6-73-3t

TELECOMMUNICATIONS CONSULTING FlRMlocated in the South has an opening for anengineer with experience in broadcast and communications system designs, preparation of specifications. feasibility studies, and preparation ofengineering reports. Qualifications include athorough knowledge of communications andbroadcast engineering fundamentals, FCC rulesand procedures. and an ability to write technicalreports. Include complete description of background. technical training, experience, and startingsalary required. in application. Reply to: BroadcastEngineering, Box 285. 1014 Wyandotte St., KansasCity. Mo. 64105 7-73-lt

REGIONAL SALES MANAGER: with experiencein selling of high quality television equipment tobroadcaster and other users territory open inrnidwest. Liberal salary. Incentive and benefitprogram. Send Resume of qualification to themarketing manager. American Data Corporation,and Airpax Co .. P.O. Box 5191 Huntsville Al35806 7-73-ItMANUFACTURERS REPRESENTATIVE:Needed in several critical U.S. areas. Must beinvolved in broadcast equipment sales and carrynon conflicting switching and terminal equipmentlines. Send Resume of qualification to marketingmanager. American Data Corporation, and AirpaxCo.. P.O. Box 5191 Huntsville, AI 35806 7-73-It

CHIEF ENGINEER full power. class "B" FMstereo with SCA. Must have prior experience andengineering superviser and full knowledge FCCrules and regs. Send resume to Gen. Mgr., WRVR,85 Claremont Avenue. New York. N.Y. 10027.

7-73-lt

This maybeyour last chanceto get up offyour big fatcomplacency.Try this. Pick out one of ourUnited Way agencies. Go out intothe field with its workers. See foryourself the very real needs of thepeople it serves. The new andgrowing urgency of their problems.

Take a good hard look at the newthings that the agency is doing tosolve these problems. The newapproaches. The new programs.The new money they take.

Then, when you pledge yourFair Share, you're bound to makeit bigger. You will remember thefaces and voices of those youare helping.

If you don't do it, it won't get done.

:'~oad'lertisi~ contributed forthe publicgood ~

<'ou,.c.'..._

Akai America, Ltd. . 23American Data Corp. . 51American Electronic

Laboratories, Inc 10Andrew Corp. . 1Audio-Video Engineering Co. . .. CE-8Belar Electronics Laboratory, Inc 9Berkey Colortran 53Broadcast Electronics, Inc. . .15,42,62Broadcast Equipment Leasing Co. .59CBS Laboratories 55Danscoll Ltd 49Dynair Electronics, Inc 29EIE - Electronic Industrial

Engineering, a Div. of RCA CE-3ES Enterprises 47Econeo Broadcast Service, Inc 38Electro-Voice, Inc IFCGates Div. Harris-lntertype Corp. . .21The Grass Valley Group, Inc 3International Aff ii iates Ine. . 64International Tapetronics Corp 56Jampro Antenna Co. . 12Jensen Tools & Alloys 59McBee Laboratories 52McMartin Industries, Inc. . 50,62Mii !er-Stephenson

Chemical Co., Inc 30Mincom Div., 3-M Co CE-5Minneapolis Magnetics Inc 49Mountain West Alarm Supply Co 59Pacific Recorders &

Engineering Corp. . 57Pentagon Industries, Inc. . 11Polyline Corp. . 9Potomac Instruments, Inc 41Pulse Dynamics Mfg. Corp 61RCA Electronic Components CE-7Ramko Research 58Roh Corp. . 60Russco Electronics Inc. . 57SC Electronics 31SeuIly I Metrotech

(Div. of Dictaphone) 5SounDesign . . . . . . . . . . . . 63Sparta Electronic Corp 7Spotmaster 15,42,62Stainless, Inc. . . . . . . 54Stanton Magnetics, Inc 55Switchcraft, Inc 43Tape-At hon Corp. . 27Tech Labs, Inc 61Teledyne Isotopes 39Time & Frequency

Technology, Inc. . IBCTracor Industrial Instruments Div 52UREI 17Vital Industries, Inc. . . . . . . . . . . BCWilkinson Electronics, Inc. . 8,48Xcelite Inc 59

WANTED TO BUYUSED/RECONDITIONED

EQUIPMENTComplete color transmission package required. Also portable microwave links, 'TVM-1or equal. Any type of color or black and whitestudio equipment-Camera's, VTR's, videoswitchers, sync generators, wireless microphones, sound consoles, remote controlboards pl us any other studio I broadcastequipment. Interested in CA'TV distributionamplifiers, line extenders and 2-way radiomobile equipment. Please write or call statingcondition, model numbers, price wanted, etc.

INTERNATIONAL AFFILIATES INC.147 West 35th Street, New York,N.Y. 10001, Tele: 212/695-8060




TheNew F~

IFldFRE"!!UEJ

R5•..,,....--- ·-r1 ~- •..•.• ....•

modulation monitors

TV (UHF & VHF)

;> o 2 I \: I 8

TFT--~-~

FCC Type Approval 3-187

AM


Since TFT introduced its first instrumentin 1971, TFT monitors have become the broadcast industry standards for reliability, accuracyand convenience. For example, in the past twoyears, more than 25 percent of the TV stationsin the U.S. have installed TFT monitors. Plusmany stations in foreign countries. What'smore, TFT's new AM and FM monitors aremeeting with the same kind of sales success.

And for good reasons: innovative designtechniques . remote monitoring without anRFamplifier ... less interference from unwanted


signals digital readouts proportional,oven-controlled master oscillator for exceptionalfrequency stability ... far fewer calibrations .digitally settable plus and minus peak flashersto prevent ambiguity ... built-in, 1OMHz generalpurpose counter ... and many more featuresyou won't find in traditional monitors.

But prove it to yourself. Just ask anyonewho owns one (a complete customer list isavailable on request). Then, let us demonstrateon your frequency. Cor·tact your local TFTrepresentative, or call us collect.




1++··11~-=~ ·-fJ:;~~O e _J-·o::r:o....L_

• Newmodular computer concept• Extremely versatile, fast and reliable• Easy operation with no computer training• Standard and custom formats available• 64 characters per line• 27 events displayed at one time• Full editing capabilities• Multiple pre-rolls without time restrictions• Full transition capability including fades, dissolves, pattern

wipes and inserts

theway

to tv

• Complete logging facilities for management aad FCCpurposes• Manual override always "hot"• Power failure protection• Complete plant communications with auxiliary monitors• Full spectrum of equipment can be controlled in any configura

tion and quantity• Events on-air -by real, elapse, duration or cue time, plus manual• Two automation systems 1n one: on-air plus 8 programmable

selections for microwave switching, VTR's into record, etc.• Optional mass data storage available for advanced scheduling

from 27 events to one year

Several stations in America now enjoy daily use of the Vital AutomationSystem.Write for your brochure describing our VIMAX-27system.

Make Vital Industries, Inc. your single responsible source for your total system needs.

Fox Hill Rd., Lynchburg, Va. 24503703/384-7001

3620 Ridgewood Rd.• N.W., Atlanta, Ga. 30327404/233-9459

GOOD ENGINEERING IS VITAL

~~z-V~IT.,.~L INDUSTRIES, INC.7960 W. Beverly Blvd .• Los Angeles, Cal f. 90048213/653-9438

2644 N. Seventh St.• Terre Haute, Ind. 47804812/466-3212

MAIN OFFICE: 3614 S.W. Archer Road, Gainesville, Fla. 32601-Pbone 904/378-1581




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