Projection engineering (Sept 1929-Nov 1930)

Projection Engineering, June, 1930 Page 15 Radio vision Bids for Public Favor By Austin C. Lescarboura. Mem. I.R.E. Mem. A.I.E.E. In Programs and In Home Equipment, Radio Television Moves Ahead at an Accelerated Pace. RADIOVISION, or radio television, is making slow but _ steady progress. Despite all that has been said about the impracticability of this young art, despite the ridicule of those who would much prefer to elect their own time and place for introducing their own version of a refined radiovision art, despite the many obstacles by way of immediate commercial exploitation, radiovision has jumped clean out of the secrecy of the laboratory and into the public eye during the past few months. There is no telling how soon radiovision may become an established industry, fully self-supporting, and, indeed, lending a helping hand to the radio industry at large which at times is in need of fresh interest. To an audience of radio engineers and workers it seems hardly necessary to point out the difference between home radiovision and telephone television. One presupposes a simplicity of apparatus that makes for low cost, and the flashing of the best possible programs, consistent with the limitations of the art, through space. The other calls for the best possible results, almost irrespective of the amount and the cost of equipment, together with as many wire channels as may be required. Thus the recent demonstrations of the telephone engineers, while considerably beyond the results obtained via radio with home equipment, have been interpreted in their true light by the radio fraternity. It is only the lay press that has drawn rather unfortunate comparisons between perfection at any price, and price with any results.. That same lay press, however, would hardly make the same mistake in judging the music of a philharmonic orchestra and that of a public school orchestra, appreciating full well the marked difference between professional talent and amateur talent. Subject Matter Interest Required Several factors have served to lend greater subject matter interest to radiovision broadcasting. Until recently, radiovision broadcasting has been largely experimental and uncertain. Transmitters have gone on the air at irregular intervals, and have transmitted simple pictures really intended for the testing of receiving equipment. There has been almost no attempt at creating an interest in the subject matter itself. Indeed, one well-known television worker has been broadcasting pictures of a little girl bouncing a ball until the lookers-in have frankly come to look upon this subject as a trade-mark pure and simple. If radiovision is to make a bid for public favor, the first step is broadcasting. Programs must have a certain amount of subject matter interest. They must be broadcast on a regular schedule. The public must know that by tuning in on a certain wavelength at a certain time, there will be pictures available. If we look back upon sound broadcasting, we note that many broadcasters were on the air prior to 1920, with purely experimental programs. DeForest operated a broadcasting station as far back as 1909, eleven years prior to the dawn of what we recognize as the broadcasting era. Yet the earlier workers were so lackadaisical in their broadcasting schedules that no one could Fig. 1. Home television. count for certain in tuning in music or speech. Therefore, there was no special incentive except on the part of those interested solely in experimentation. Likewise today, the interest in radiovision has, until now, been solely experimental. The layman would not bother with it. But with the advent of regular programs, containing some subject matter interest, the layman is prepared to buy equipment and to tune in on pictures, even if they are relatively simple and crude. Double Transmitter for Sight and Sound One of the handicaps of present-day radiovision broadcasting is that most workers employ only one transmitter, which must serve as their laboratory as well as broadcasting equipment. Changes and alterations are made in the transmitter, causing a disruption of broadcast schedules. After all, there should be available an entirely separate transmitter for broadcasting, so that no alterations or changes could possibly cause any interruptions in the programs themselves. This is a point which will have to be observed if the commercial side is to gain in importance. In fact, most of the radiovision broadcasting efforts until now have smacked of the experimental laboratory. Pictures have been sent out in reversed form. Sound accompaniment has been out of step. Monitoring has been faulty. Announcements have been crude. All in all, there has failed to be incorporated the perfection of good showmanship; hence the appeal has been solely to experimenters, limited in numbers, rather than to the laity which is the deciding factor in a commercial success. For the most part, broadcasts of radiovision subjects have been in the form of special films placed in a film pickup machine, or again actual subjects scanned by a beam of light. The special film subject has much to recommend it. Subjects may be filmed under the most satisfactory conditions, particularly regarding lighting. It becomes possible to syndicate a given subject to a number of scattered radiovision stations, thereby building up a network without the cost and problems of a wire hookup. However, in actuality the main drawback has been the repetition of the film. Broadcasters have used the same film over and over again, which is but natural, perhaps, but certainly serves to kill the subject interest. While this might be pardonable during the experimental era of radiovision, it is unpardonable when public interest is being solicited purely on the grounds of entertainment. The use of the scanning beam has also presented certain drawbacks. The subject must be scanned in a darkened room, which precludes picking up outside subjects. Quite a while ago the telephone engineers disclosed the daylight pickup technique, with the subject fully illuminated and with the scanning taking place in a television camera. This device comprises a revolving scanning disc, a photographic lens, and a photoelectric cell. The properly focused image is scanned in the camera itself. New Camera Recently, some interesting radiovision broadcasting has been bandied by direct daylight pickup, employing a novel form of television camera. The Jenkins Television Corporation engineers have developed a camera which is at once simple and effective. It is in the form of an angle-iron frame, mounting a case at the top representing the television camera proper, and