Pictures to be Regularly Radiated

Radio Record, Volume II, Issue 11, 28 September 1928, Page 32

Pictures to be Regularly Radiated

by

B.B.

C.

NLY a short while ago, the British Broadeasting Corporation stated that while sympathetic with the development of picture radiation, it could not undertake any such system. The engineers of the corporation have kept themselves in touch with this field, and have now definitely decided to undertake still picture transmission from Daventry, 5XX. The transmissions will, if the public so desire, be included in the regular programme hours. The Fultograph system, as apart from television, is to be employed. Although picture transmission is still in the experimental stage, this’ move on the part of a body so conserva: tive as the B.B.C., predicts an important future for this science. American stations have, for some time, been regularly transmitting pictures. although by a different system. Good results have been obtained. but it cannot be said that picture transmission is vet definitely established. This science is to-day where wireless was in 1921, and it is very unlikely that either New Zealand or Australia will undertake anything of the nature cutil something more definite has been established. However. this move by the B.B.C.. especially in the adoption of the Fultograph system in preference to ftelevision, is of no minor significance. The Fultograph System. [ys discussing the system with an official of the B.B.C., the inventor Japtain Otto Fulton. remarked: "My apparatus is as simple asa cart-to a eart there are only wheels and the body. and if you take any of them away it is not a cart any more." The apparatus is certainly simple. On the top of a box is clockwork which

revolves slowly a cylinder like the eylinder of an old type phonograph cylinder. Semi-absorbent ° paper. dipped in chemical solution, is placed round the eylinder and -a platinum needle traces out in 83 minutes an easily-recognisable portrait. It is claimed that a one-valve set with a suitable arrangement to replace’ the loudspeaker can reproduce the pictures a distance of one mile from the transmitting station. Beyond this mere valves are required. When a photograph is to be trans. — mitted a negative is printed on a sheet of zine or copper foil coated with sensitised fish glue. During the printing the glue exposed to the light becomes insoluble. Washing the glue removes the portion that has not been exposed to the light, leaving an insoluble image. This is hardened and inpressed into tin. The glue picture is wrapped round the cylinder and as the cylinder re volves a metal stylus moves over it. The glue acts as an insulator, but when the stylus touches it a current passes and is transmitted. A somewhat similar arrangement at the receiving end causes an identical picture to be traced out. In Use At Vienna. VNAPTAIN FULTON and his fourteen assistants have done their experimental work in Vienna. His aim has been to put picture reception within the reach of the man in the street. "All the time I have tried to simplify radio picture apparatus for the man aft

home," he told a representative of the B.B.C. The present Fultograph apparatus will cost about £15, and anyone will be able to use it. It is already in use in Vienna, where every day a news picture, a sport picture, and a fashion plate or children’s joke are broadcast. The received pictures are 44in. by 3%in. Television. ITH this term are associated many names, perhaps the best known being that of Baird, the Scotsman. This inventor has evolved an apparatus to enable the vision of living and moving beings, objects and scenes to be transmitted by wireless or land line in a manner similar to that in which sound is transmitted by wireless and telephony. Four deviees are required to adapt the art of radio to television. two the photo-electrie cell, and the neon "flash" lamp-are the "eye" and the "paint. brush" respectively, of the radio television apparatus. The other two essentials are the scanning mechanisms of the transmitter and the receiver. The principle is based on the fact that the human eye ean he focused on an area only the size of a pin-prick. To receive a sharp impression the eye must momentarily focus on each point on the object. Television apparatus breaks up into points the image which is to be televised. and restores it again. point by point. into a perfect whole at the receiving end. We are accustomed to think of the images presented to our eyes as even.

unbroken scenes. Such is not ‘| case There are minute holes in our 1 of sight which is composed of a nyultitude of little impressions fitting closely together. At twenty to thirty inches from the eye a crack ,of 1-100 of an inch will vanish. ; Advantage of this is in making illustrations for printing purposes, and this principle has been applied to television. If a scene can be broken before the television transmitter into small dots and reproduced, each according to its corresponding brightness, in the game relative position at the receiver, the picture can be reproduced with such necuracy that it will be acceptable to the eye. If this can be done at the rate of about fifteen times a second, a continuous moving picture can be reproduced at the receiving end. This is television. The Systems Compared, and Contrasted. ITHOUT having to go into the details of the equipment, it will be clenr that there are remarkable differences between the two. systems. In that both are a modification of the wireless waves and result in the transmission of pictures the systems ure alike. Beyond this the similarity does not exist. One transmits still pictures and the other moving ones. The system to be used by the B.B. C. has much in its favour. It is efficiert and cheap. and can be used now. Teleyision is a science of the future. New publieations are pregnant with fresh ideas, but few are, at the present time. workable. Moving pictures. sporti everything is within the range of tel vision and imagination is reluetant ft remain in any one field. so great is its secope-but its realisation is yet to be.