Radio today (Sept 1935-Dec 1936)

THRU THE LAB KEYHOLE — television pictures shown in Philadelphia home — Philco engineers transmit from 1-kw. station 7 miles — experimental receivers deliver 345-line pictures • TELEVISION PICTURES of great clarity and brilliance — steady and absolutely unflecked by blemishes were transmitted to a Philadelphia home, 7 miles from the Philco television laboratories, August 11, for the inspection of a group of newspaper men. In the studios different girls sang different types of songs in contrasting fashion, and the distant audience voted its choice. A boxing bout and a male quartet were also televisioned. Boake Carter addressed his fellow newspaper men on "The Freedom of the Air," and then, called by telephone, was interviewed by members of the audience, while the rest "looked on" on both sides of the conversation. A motion-picture film followed by television. A 36-tube set The experimental home television receivers used contain 36 tubes in all, and are of the cathoderay type, with vertical cathode-tube viewed in a 45deg. mirror. The three knobs for control of the 51-megacycle "picture" are grouped on one side of the console front; the three "sound" knobs on the other. The 51 mc. "picture" and 54.25-mc. "sound" are tuned separately for flexibility, but single-knob control can easily be accomplished. So simple is the tuning, that inexperienced persons can quickly bring in good pictures. Once tuned and framed, the pictures were stable on the screen. In general, the new television receivers resemble ordinary large home consoles. Sayre Eamsdell, Philco vice-president, presided at the tests, and with A. F. Murray, television engineer, issued detail specifications of the Philco television system, as follows : Channel width 6 mc. Spacing between tele vision and sound carriers 3.25 mc. approx. Polarity of transmis sion Negative Number of lines 345 Number of pictures per second 60 interlaced Aspect ratio 4:3 Percentage of televi sion signal devoted to synchronizing 20% Synchronizing signal Narrow vertical Carrier frequency of picture transmitter 51 me. Carrier frequency of sound transmitter 54.25 mc. Picture 7 in. by 91/ in. Color Black & white Larry Gubb, Philco president, commented that commercial television "will not come in 1936." Home receivers at the beginning may cost $500, he estimated. Sayre Ramsdell, Philco vice-president, who presided at Aug. 11 demonstration of television in the home. J". M. Skinner, president Philadelphia Storage Battery Company and chairman of the RMA television committee, declared that to speed up commercial television, a patent pool should be set up something like that established in the automobile field. Under his plan each manufacturer would contribute his own patents to the pool, and would in turn get the use of the patents of others without cost, so that everyone would receive the benefit. Td evision pool Experimental home-television set by Philco, front and rear. Cathode-ray screen is viewed in 45-deg. mirror. Sound knobs on left, picture-control knobs on viewers' right. Pictures black-and-white, 345 lines, 6-mc channel. Mr. Skinner commented on the need for television standardization, a continuous television band, and multiple television programs in the same area. In the proposed 42-90-megacycle band, most of the work so far has been done in the 42 mc. end, but very little at the 90 mc. end. If, however, the band assigned television by the FCC is not continuous, but is widely scattered, "you can kiss television goodbye for some time to come," in Mr. Skinner's words. What the price of the initial television sets may be really doesn't matter, according to Mr. Skinner. Television will reach its own level of receiver costs and operating expense, and sets may range somewhere between $250 to $750,' but the many factors of expense of programs, relay stations, coaxial cable links, etc., will all enter into the final problem of television costs. 22 Radio Today