NAEB Newsletter (Dec 1957)

bolt through the mast enables the antenna to be oriented for maximum response. A short mobile run (100 ft.) is then made with the antenna at 80 feet. An average value of field strength is taken over this run as the measured field. The mast is then lowered and secured and they’re off to the next measurement. Rob Beldon, WILL chief engineer, says the mast and channel iron cost less than $15 including one mast which was bent before they decided that the bracing shown was necessary. The field intensity meter is mounted temporarily on a desk in the truck with power supplied by the truck battery. Beldon may be seen in front of the truck. If you look closely, Clarence Berbaum may be seen inside the truck and A1 Saldeen could be seen at the right of the picture if we hadn’t cropped it to fit the column. The FCC also recently denied a petition which asked that UHF stations be permitted to broadcast music and other purely aural programs while tele¬ casting still pictures and slides for a part of the broad¬ cast day. The FCC rule is that television aural and visual transmissions must comprise integral parts of the announcement or program and have a substantial relationship with each other. ***** The first production model of the Ampex Video¬ tape Recorder is scheduled to be completed in Nov¬ ember. Among the new features announced by Am¬ pex are complete interchangeability of tapes among all production units and a means of editing the recorded tapes without loss of synchronization. Production models are priced at $46,000 and a delivery schedule set up earlier this year is expected to be maintained in spite of a strike which shut down production for a month this summer. Over 100 units have been or¬ dered to date. ***** An excellent paper on “Television Film Stand¬ ards” was presented at the recent SMPTE Conven¬ tion in Philadelphia. The authors are K. B. Benson and J. F. Whittaker of CBS Television in New York. In the paper, standards for control of the combined motion-picture and TV system are developed by an examination and correlation of the relationships be¬ tween the two component processes and the effects upon the end product. It’s a paper of interest to all TV engineers and will no doubt be published soon in the SMPTE Journal. Included in the seventy four papers presented at this five day meeting was one by John R. Brugger, Chief Engineer of the Washington County Closed Circuit Television Network. John’s paper covered a description of the equipment and the facilities used at Hagerstown. While in Philadelphia we had the opportunity of visiting the studios of WHYY-TV and being con¬ ducted on a tour of their new facilities by Samuel Barbour, Chief Engineer. He reports that present programming from 9:00 a.m. to 3:15 p.m. is primarily for in school use. Programming will be expanded later to include evening hours. Reports of excellent re¬ ception on Channel 35 are very encouraging, Mr. Barbour states. WHYY-TV has a 12y 2 KW RCA transmitter with an ERP of 155 KW from a 500 foot tower. * * * * * A television film camera for $89.50! That’s what Merlyn Rawson paid for a surplus iconoscope camera which he has modified for use at the University of Southern California Telecommunications studio at Los Angeles. While the definition can hardly be cal¬ led broadcast quality, (about 250 lines) this ike chain enables them to integrate film and slides with live pic¬ tures from the vidicon cameras used in teaching TV production. The unmodified camera has free running oscillators and internal sync such that the video signal is suitable for feeding a monitor. However, the modification necessary to use standard RETMA pulses is very simple. A type 1846 iconoscope tube is used as the pick up tube. Since this is not available from stock, a spare camera tube was provided by purchasing a second camera. By the use of a simple mirror multi¬ plexer, pictures from either a slide or film projector can be projected directly on the mosaic of the icono¬ scope. The camera filaments operate from a 28 volt dc supply although instruction sheets furnished with the camera provide for AC operation by filament and plate rectifiers. A plate voltage of 400 volts at 175 mils is required as well as 50 volts of bias. This camera was built by RCA for aircraft use. We can tell you where it may be obtained on the West Coast although we’ve seen it advertised elsewhere. The data DECEMBER, 1957