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Show Goi 01 q tottie Movies' Wlli Ic JfittflfBO cut Ho ITS 6 111 '''$ -.rC 5 . - iff t -Vr 4 i V H T - "v zr . : : h"r 1 1 1 By ELMO SCOTT WATSON VA' E " k IVN. 01X0 to the movies while A 'wj sitting at home! Doesn't X - -V j sound possible, does it? $ 'i4Sx" -'"mX It not only is possible, g IS ' ' 5 but, Judging from a dem- fss,!f I P '''v'lW onstration made In East Si T - s' I ) ! V x ' Pittsburgh, Pa., recent- f 1Ui fiA'' 1 F " & ly, that seeming miracle f ijCT" IT j 1hs .t i may soon become one of I flW-l-4- "j j the commonplaces of f . t UtfKlKn Y; ill our daily life. fS,, I i ? f' VI4 1" v Recently there gathered in the tel- f t I W fl VPl f evision laboratory of the Westing- 1 M 1 4 lFT J. . house Electric and Manufacturing IS- "VTjf-J5 I -fT3 company a group of radio leaders, , 1 V L, . j among them representatives of the X. as ' sv "t-ir--Ss-rf f's sr ltadlo Corporation of America, the V p 1 1 ,,?J. Zfb 4 National Broadcasting company, the i J " "'i us 1 'S'V General Electric company and the N n ? " J-t estinghouse company, who saw mo- v , "t " r tion pictures which, broadcasted from Ji,v" a station nearby and transmitted on JaH&aii- V radio waves, were picked up on a re- , " By ELMO SCOTT WATSON OIXG to the movies while sitting at home I Doesn't sound possible, does it? It not only is possible, but, Judging from a demonstration dem-onstration made In East Pittsburgh, Pa., recently, recent-ly, that seeming miracle may soon become one of ; the commonplaces of our daily life. Recently there gathered in the television tel-evision laboratory of the Westing-house Westing-house Electric and Manufacturing company a group of radio leaders, among them representatives of the liadlo Corporation of America, the National Broadcasting company, the General Electric company and the Westinghouse company, who saw motion mo-tion pictures which, broadcasted from a station nearby and transmitted on radio waves, were picked up on a receiver re-ceiver In the laboratory and reproduced repro-duced before their eyes. It was the world's Drst demonstration of radio movies and possibly the most astounding astound-ing of the many advances In the science sci-ence of radio announced during the past year. While radio movies are still in the laboratory stage, Westinghouse officials, offi-cials, under whose auspices the demonstration dem-onstration was made, declare that the event heralds the day when the radio listener will sit at home and hnve that most popular form of entertainment, motion pictures, projected by his individual indi-vidual radio receiving set. The development of radio movies Is a trhyuph of scientific engineering. During the Inst summer, the Idea came to the mind of Dr. Frank Conrad, In charge of this branch of his company's activities and the fact that in barely two months he brought the device to the laboratory stage In the degree of perfection witnessed at the recent demonstration, dem-onstration, Is said to have set a record. rec-ord. Radio movies are a step beyond previous developments In television and required the invention of a number num-ber of appliances In addition to a great deal of scientific calculation, synchronism of various high-speed mechanisms, and accurate control of light and radio waves. Although the sending of moving pictures pic-tures by radio, as may well be imagined, imag-ined, required mauy complicated and delicate pieces of apparatus, the principles prin-ciples of the art as explained by Westinghouse West-inghouse engineers, are not beyond ordinary comprehension. Photography In Its simplest form consists of the reproducing re-producing of spots of light and shadow shad-ow In the same arrangement as they appear In the subject photographed. The screening of a motion picture, of course, requires that a roll of film be operated at a speed which sends sixteen pictures a second before a projecting beam of light. Because of the structure of the human eye, If a series of pictures follow each other at the rate of sixteen or more per second, the human eye sees It as a single moving mov-ing picture. All this the broadcasting of radio movies requires, with the addition that the spots of light must be transformed trans-formed Into frequencies, some of which are In the audible range, transferred trans-ferred to a radio wave and broadcast as electrical energy. In receiving the pictures, the process is reversed, the electrical energy Is picked up, and the frequencies returned to lights and shadows, which wrten viewed presents the radio movie. In the first step of the process a pencil of light traverses each picture, 1. The heart of the television motion mo-tion picture transmitter. The scanning scan-ning disc is clearly shown as well as the dot of light which is thrown upon the motion picture film. Above the scanning disc may be seen the synchronizing syn-chronizing tube which keeps this disc turning at a predetermined speed. 2. Dr. Frank Conrad, assistant chief engineer, Westinghouse Electric and Manufacturing company and inventor of the television motion picture projector. pro-jector. The scanning disc of the apparatus ap-paratus is immediately in front of him. $ : e or "frame," as It Is called, at the rate of sixty times a sixteenth of a second. This process produces a sixty-line picture, pic-ture, as clear as the usual newspaper halftone Illustration. The pencil of light is produced by a scanner which is a disc with a series of minute square holes near its rim. The disc is so arranged that all light Is excluded exclud-ed from the film except that which goes through the square holes. The disc turns very fast, and as it turns passes the beam of light across each "frame," with the result that an Individual Indi-vidual beam of light touches every part of the "frame." The heam of light passing through the film falls uion an electric eye or photo-electric cell, which Is not unlike an oversized Incandescent lamp. Within With-in the cell, however, Is a metal whose electrical resistance varies with the light falling on It. Caescum, a rare metal. Is used In the Westinghouse cell. The amount of light falling on this cell determines the amount of current passing through It. The result re-sult Is that each individual beam of light sends an electrical Impulse which varies directly according to the amount of light or shade In the film through which It passed. The beams of light have now become be-come electrical impulses and are sent on to the broadcasting station. Here the beams assume definite and varied frequencies, some of which are audible. audi-ble. Doctor Conrad states that these frequencies range from somewhere near 500 to approximately 00,000. Since the human ear is limited to frequencies frequen-cies of approximately 15,000. much of the radio movie wave Is Inaudible. At the broadcasting station these frequencies are transposed on a radio wave and transmitted exactly as the ordinary music or voice. The radio signals now can be sent across a room, or across the continent. Their distance dis-tance range Is limited only by the broadcasting station's equipment. In the Westinghouse demonstration, the signals traversed a distance of about four miles; two miles from the laboratory labora-tory to the broadcasting station by wire and two miles back to the laboratory lab-oratory by radio. To turn these radio waves back Into In-to light, an arrangement which permits per-mits the use of a mercury arc lamp is used. By this adaptation the weak radio currents control the action of the many times more powerful current operating the arc lamp. This action may be compared to the action of a radio tube, where the weak radio current cur-rent on the grid of the tube controls the action of the Independent and more powerful plate current. Thus the mercury arc lamp goes bright or dim as fast as the current changes, and its light at any instant Is in proportion to the light that the electric eye sees In the same Instant To return the dots of light to their original pattern, another revolving disc or scanner Is also used which Is similar to the transmitting scanner. The use of a mercury arc lamp permits per-mits the radio pictures to be thrown upon a ground glass or screen, the first time this has been done with television tel-evision apparatus. Both these scanning discs turn at exactly the same speed; the bole In the receiving disc must be exactly In the same relative position as the corresponding cor-responding hole In the transmitting disc. In other words, they must be synchronized. Westinghouse engineers were the first to develop a feasible method of synchronism, and their method was by means of radio. From transmitting transmit-ting equipment, which may be located in the broadcasting station, they transmit trans-mit a constant frequency wave of 5,-(KK) 5,-(KK) cycles. This wave Is produced by a tuning fork and transmitted over a special carrier wave from the broadcasting broad-casting station. The constant frequency fre-quency note Is received on a special receiver and by means of special apparatus ap-paratus controls the speed of synchronous syn-chronous motors, which drive the scanning discs of both transmitting and receiving radio movie equipment. This revolutionary method of controlling control-ling equipment Indicates, In a measure, meas-ure, the extent to which science must go In order to perfect television or radio movies. But the developments In radio during dur-ing the past year, and especially this latest development Indicates tint the word "impossible" Is rapidly being written out of the vocabulary of American electrical engineering genius, nnd that radio movies for all who care to enjoy them are an assured fact. |