The international photographer (Jan-Dec 1938)

12--DECEMBER, 1938 INTERNATIONAL tinues, then British television is justified in hoping for better days ahead. Considerable mystery surrounds the question of how many television receivers are actually in use. Estimates in British publicatios vary all the way from 2,000 to 9,000, depending apparently more on what the writer is trying to prove than on any reliable count. The most probable total appears to lie between 3,000 and 4,000, which, in a population of 10 million within the service area of Alexandria Palace, is a melancholy showing. And yet no one conversant with the situation as a whole can or does regard it as an evidence of failure. The reason is, that while sales have lagged, public interest has been sustained, and where there is interest there is a potential market. That interest is unmistakable, and it has impressed even critical visitors from abroad. Among other manifestations it has expressed itself in a persistent demand for the extension of television service to the Midlands and the North, even while London has failed to justify the expense of what is already offered. The experience of the British Broadcasting Corporation in this respect gives point to the caution with which American interests have ventured into the terra incognita of television. In the United States the cost of nationwide urban coverage is staggering; even in England it is serious. Once the service has been undertaken it is almost impossible to discontinue it, and if it is to be continued, sooner or later it must be expanded. Even if eventually it gets over the top and produces profits and employment, it may for a time dislocate existing industries. Thus in England, together with the agitation for television transmission in the provinces, there are outcries in the trade that television ballyhoo is ruining the sale of sound receivers without creating a compensating market for television receivers. A parallel complaint points to the unfairness of taxing eight million licensees of sound receivers for the maintenance of service to a few thousand owners of television apparatus. Nevertheless, with all these difficulties, the outlook for British television has its bright spots. The technical progress we shall discuss later. Studio programs have improved, although it is generally agreed that they are still far below the average enterta;nment level of motion pictures and aural broadcasting. The real achievements — and these account in large part for the unflagging interest in the new art — are visual broadcasts of sporting and ceremonial events. The importance of the Coronation procession telivising was referred to in our 1937 report. It has been followed by other events of scarcely less interest to the British public. On June 1 of this year the Derby was televised, and prize fights, boat races, soccer games, tennis matches, etc., as well as the more solemn spectacles featuring the royal family, have been received via radio with general approbation. Whatever the technical limitations may have been, the unique sense of psychological immediacy, the vantage points at which the television cameras may be set up for thousands of eyes instead of the few that can be physically accommodated in such favored locations, and the skillful showmanship with which the events have been scanned, have captured the popular imagination and drowned out the voices of pessimism. Progress in both transmission and reception, while without revolutionary innovations, has been steady and many-sided. In the field of theatre television, during February of this year Baird demonstrated a mechanical two-color system affording an image 12 feet by nine feet, but with only 8.33 pictures per second and 120-line definition. High-definition television in monochrome was shown by Baird in a Gaumont-British West End theatre, notably on June 1 on the occasion of the Derby broadcasts. The picture was relayed bv short wave from Epsom Downs to Alexandra Palace, thence broadcast and picked up at the theatre on a screen eight feet by six feet. The intensity of illumination was low (about 0.75 foot-candle), necessitating the turning off of house lights; otherwise the results were good. A competing company, Scophony, televised the Derby at another theatre. This organization employs an optico-mechanical system of considerable scientific as well as practical interest, utilizing a light-control cell which works on the principle of diffraction through compressional waves generated in a liquid. The method affords higher screen brightness, but appears to be subject to synchronizing difficulties at the present stage of development. The consensus of opinion among large audiences at these and other demonstrations was that theatre television, while nowhere near the quality standard of 35 mm film projection, had reached a stage where it could add the entertainment value of topical broadcasts to film programs, especially in short-subject houses. British Gaumont Equipments announced last June 3 that television apparatus should shortly be available for theatres at a cost of about 1,000 pounds ($4,800 at the present rate of exchange) but no installations have been reported. Apparently the principal obstacle is the re'usal of the BBC to permit reproduction of its broadcasts for paying audiences because of copyright complications, while at the same time the Television Act of 1937 makes transmission by radio a government monopoly, and unless amended will not permit a private corporation to broadcast its own pictures to a chain of theatres. In the field of home receivers there has been development in opposite directions, viz., larger pictures at higher cost and less expensive receivers at the sacrifice of picture size. The latter are the equivalent of midget sound radios, with two important differences. The midget sound radio, while it has acoustic defects, can be heard all over a room, like a large set. A table television receiver, with a screen from five inches bv four inches to 71/2 inches by six inches, is suitable only for close viewing by a few persons. A midget sound radio is really cheap. A television midget is still priced at 30 to 40 pounds ($144.00 to $192.00 at the present rate of exchange). Large pictures are available — but at a price. A few examples: a Baird model incorporating a cathode-ray projector, picture size 24 inches by 18 inches, at 157V2 pounds ($756.00 at the present rate of exchange) ; an Ecko-Scophony mechanical receiver with a picture 24 inches square at 231 pounds ($1108.00 at the present rate of exchange) ; a Philips Radio projection type receiver, picture size 18 inches by 14 1/2 inches, at 126 pounds ($604.80 at the present rate of exchange). It is true that pictures of this size may be viewed by thirty or more people, but they are also most convenient for smaller gatherings. Under the circumstances, however, the intermediate size of picture afforded by a 12-inch cathode-ray tube — 10 inches by iy2 inches — is still the rule; these instruments cost in the neighborhood of $300.00. For those who build their own receivers a cathode-ray tube giving a 12 inch by 10 inch picture is available at about $75.00. Some sixteen British manufacturers are offering television receivers, but it is evident that even at the peepshow level their product will not assuage the poor man's lot, nor even those in middle circumstances, with taxes at the rate of five shillings to the pound. On the transmitting end, an eight-studio layout is projected for Alexandra Palace, thus obviating the almost insuperable difficulty of turning out shows from a single studio which must be used for both rehearsal and production. (A second studio is being currently added.) Four Marconi-E. M. I. cameras with greatly increased sensitivity are now used in the studio. The program hours are two a day, three hours on Saturday, and one and one-half on Sunday. The transmission standard remains 405 lines, 50 frames per second, and the Postmaster General announced on January 1 that there will be no change at least until the end of 1940, thus dispelling apprehensions of receiver obsolescence for three years from the date of the announcement. For outiid pick-up a second mobile radio unit has been provided. In addition, an equalized cable network is being installed in those sections of London, such as the theatrical district, where telivisible events occur most frequently. This will provide an alternative to the radio link and require only a scanning truck at the point of pick-up. A coaxial cable laid between London and Birmingham, and shortly to be extended to Manchester, although designed primarily for telephone purposes, may eventually be used for chain television. It has been found that under favorable conditions the Alexandra Palace pictures may be viewed at distances of the order of ten times the calculated service range of the station. The normal or optical range is only 25 miles, but authenticated reception has been reported from Ormesby, near Middlesbrough in York, 220 miles from London and almost spanning England from south to north. The pictures have been viewed repeatedly at distances of the order of 100 miles. Such feats require special receiving aerials on hills, and the reliability and quality of reception is necessarily doubtful. However, they indicate the possibility that as additional data accumulates on the propagation of the quasi-optical waves I used in television, it may be found that the stalions have a somewhat greater service range than has been expected. Thus Alexandra Palace is now regarded as having a useful range nearer 50 '• miles than 25. Should this prove generally true it would be a matter of no small importance, since doubling the radius quadruples the area covered, and by increasing the population within range of television transmitters would materially reduce economic difficulties of distribution. Germany. At this writing experimental transmissions have begun from a transmitter on the \ Amerika-Haus in Berlin. The power is between 15 and 20 kw, or approximately the same as London, which is rated at 17 kw. The definition is the same as in the United States, 441 lines, , and the frame frequency 50 per second. Two other transmitters are planned, one on the Brocken in central Germany, and one in the Taunus Mountains in the west, all to be connected with coaxial cables. Studios are designed for sixcamera operation. A picture 12 feet by 10 feet has been shown in a theatre by Fernseh A. G., which has a crosslicensing agreement with Farnsworth in the United States. There are also reports of a 700line image. Cathode-ray tubes up to 26 inches diameter have been built. The cost of receivers is said to range between $175 and $1,000, with $320 as an average. The Germans have had a television-telephone service in operation between Berlin, Leipzig, and Nuremberg for some time, and this summer the coaxial cable was extended to Munich. Mechanical scanning at 180 lines, 25 frames per second is used, and the reproduction is reported to be considerably distorted and not free from flicker. The principal attraction is novelty. The cost of a three-minute conversation is only RM 4.80 ($1.92), plus a small charge for notifying the person called; both parties must of course be present at the televising points in their respective cities. France. The Eiffel Tower transmitter is rated at 25 kw, which is more powerful than Berlin or London. Its signals have been viewed at Brighton, 180 miles distant. The station transmits daily for 2 1/2 hours. There are reports of a 12 foot by nine foot theatre demonstration, with quality approaching 16 mm projection. We have not come across any information on home receivers or the extent of distribution of programs. Developments in the U. S. The RCA-NBC experimental transmissions from the Empire State Tower in New York City were