Television Tests Begin At Last

Radio Record, Volume X, Issue 7, 28 August 1936, Page 9

Television Tests Begin At Last

Unfortunate Muddle About Television and This Year’s Olympia-Manu-facturers Don’t Know Whether to Exhibit-British. Television -. Definitely Superior to German.

Londen, August 3. TWO big events in radio will occur this month: The Alexandra Palace television station will at long last begin to transmit its first test programmes rand the Olympia Radio Exhibition, the annual fuir of Britain's radiv manufacturers, will be held. There ‘have been many disappointments and

delays with the B.B.C.’s high definition station at the old Alexandra Palace on Muswell Hill, but only to-day I saw that the aerial arrays on the 220-foot mast had been finished. Though ali the transmitters -are-not yet ready,.. some are, and simple. tests are certain to be heard, and seen, within a few days. . . NCIDENTALLY, there has been ‘a. glorious muddle over television and th. Radio Exhibition, Last year the manufacturers put a ban on television sets at.the exhibition, declaring that,

as there were no transmissions, it was pointless to exhibit television apparatus. Privately, they admitted fears that the coming of television would stop the sales of sound receivers, This year they raised the ban and were prepared to give a demonstration of domestic television as it will be received in the home. But the B.B.C. could give no definite undertaking that the Alexandra Palace station would be ready in time for the show. : So at’ the time of writing there is confusion and uncertainty in the trade. Manufacturers do not Know whether to show their apparatus. If they do there is i possibility that they may have to do so with blank screens. FTER my last visit to the Berlin Radio Show, where a whole hall was filled with working television receivers, I feel disgusted . with the Olympia ‘situation. And my feelings are aggravated by the knowledge that British television

is better than German, if only the public could see it! A dictator cer- _ tainly has his uses on occasion. However, it, may be that by the time these lines appear in print the situation will have changed for the better. Allwave. CCORDING to’ present ‘indication’. the Radio Show.’ will be an allwaye exhibition. Most manufacturers will be showing allwave sets of yarious kinds." There will also be a number of ingeniowvis refinements. _ For years manufacturers have been striving to obtain one-knob control, and have claimed to have accomplished it in one form or another. I have‘already seen

for this year’s show a set with genuine one-knob control. Its single knob works on a_ ball-and-socket principle. Rotate the knob and you effect the tuning. Push it in various direction: and you control yolume, . sensitivity, ete, Survival. . RETERNING to’ the subject of tele’ vision, I saw recently a’ demon: stration of a most interesting kind. It was television oh a screen measuring five feet by four, worked on, a nove! system called Scophony. The most re markable feature of this method of television: is that it ‘is.a survival of mechanical methods of réception which. it was thought, had been killed by the electrical method involving use of the cathode ray tube. Not only ‘is it a survival, but it is a. very lusty survival.. The optical principles involved make it easier to produce a big screen picture than when the cathode ray. tube is used. The drawback appears to be that the picture is not so bright or, in my opinion, so detailed as the cathode ‘picture. Hoivey er, votaries of .Scophony dispute the contention regarding detail, fae gg Only 250 Volts. COPHONY receivers use only a small filament lamp .as the light source, similar to that used in a-car headlight. They require only 250 yolts to operate them, compared with the 1000 volts .or more needed by the cathode ray tube. The Scophony picture is flat, not slightly curved like that thrown on the bottom of cathode ray tube. (It .is, of course, the. bottom of the "magic bottle" called the cathode ray tube which .serves as. the screen: and hitherto. this has. been curved.) ;The Scophony receiver’ marketed for-domestic use will show a picture 1€ inches by 12 inches, The marvellous little "scanner," one of its fundamental secrets is a tiny glass bar, only about an inch and a half long, ‘with’ many facets. + It. revolvés at 18,000 revolutions a minute. . In the domestic models. ad "small noiseless motor. which requires no oiling is be ing incorporated, The motor and al the essential gadgets of the sy stem wil) be contained in-a box ‘measuring. four inches by two and a half.’ Apart from the- mechanical. side of’ the: invention, new optical principles ate involved.