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Public tests begin at Berlin 'Funkturm'.
Hitherto high-definition television on tests in Germany have been confined to scientific laboratories and a few expert amateurs. To-day (Friday) a regular sight and sound service begins from the Broadcasting Tower in Berlin and all members of the public can participate.
The ultimate aim of those responsible for broadcasting in National-Socialist Germany is to make it technically possible for every German not only to listen to the speeches of the Fuhrer but also to see him speaking. The present development of broadcasting has made the first aim possible, and now work is being speeded up to provide a suitable television service so as to realise the second.
The German Post Office laboratories started high-definition test transmissions in August, 1933. At that time 90-line pictures were broadcast. A few months later, in 1934, a second ultra-short-wave transmitter was provided and this was used for 180-line pictures, the accompanying sound being broadcast by the older transmitter. These stations operate with a power of 16 kW, but the long feeder line up the Witzleben radio tower which supports the two dipole aerials, 430 ft above ground level, consumes a portion of this. Taking this into account and making use of the usual Copenhagen formula for calculating power of broadcasting stations, the power in the aerial can be said to be approximately 1.5 to 2 kW, a very large amount for ultra-short waves.
Thirty-Mile Range
A close-up of one of the ultra-short-wave transmitting aerials and counterpoises at the top of the Berlin broadcasting tower.To-day (Friday) two transmitters open a regular service of sight and sound programmes for all members of the German public who care to buy television receivers.
Up to the present the reception of these test transmissions, which have taken place for several hours every day, has been limited to scientific laboratories and to those television amateurs capable of building their own ultra-short-wave receivers and of handling the high voltages required for successfully operating cathode ray tubes. The Post Office engineers broadcast strips of film, and although these were often interesting there was no definite programme, and one could therefore not talk of entertainment value. The German Broadcasting Company's decision to start supplying regular programmes will be welcomed by all concerned in Germany, as now the question of supply of receivers will come nearer solution.
The German Loewe Cathode Ray television receiver for 180 line reception. The picture shows the receiver chassis and the tube withdrawn from the cabinet.
One German firm, Loewe, claim to be able to supply all-mains operated sight and second television receivers for RM. 600. These receivers are comparatively simple to operate and have already been demonstrated in London to the Television Committee as well as in Berlin.
Another German firm, Telefunken, supply a much larger type of apparatus, although the actual picture is not very much bigger. At the present moment it is not to be expected that a large number of the German public will buy television receivers. The broadcasters, however, have ordered a certain number from both companies, and these receivers will be suitably distributed in the service area of the short-wave transmitters. Tests have proved this to be within a radius of some thirty miles from the radio tower. The persons entrusted with looking-in will then be asked to provide constructive criticism both as to the nature of the programmes and of the actual practical working of the receivers and the entertainment value achieved. Meanwhile the German Post Office laboratories and Telefunken are hard at work perfecting a system of electrical scanning, and are also working on the problem of suitable amplifiers and cables to provide for an even higher degree of definition than the present 180 lines.
In Germany it is generally accepted that 180 lines is the minimum for a television service with entertainment value. On the other hand, the difficulties of practical high-power ultra-short-wave broadcasting with even higher definition are at present considered to be too great to warrant the further retarding of the public television service. It will be remembered that in Germany 30-line transmissions never took place on any large scale, and therefore, as far as the German general public is concerned, they are still strangers to television except for what they have seen at the various radio exhibitions. One hundred and eighty lines and twenty-five frames per second means a frequency band of 500,000 cycles for transmission, and 240 lines would mean one million cycles. Most people realise that this is too big a jump, especially when a practical system of 180 lines actually exists and suitable receivers are available.
Television News Reels
Television reporting van with which events will be filmed for subsequent transmission in the high-definition test programmes.
The opening of the television service, which was first scheduled for the second week in March, has now been definitely fixed for today (March 22). Programmes will be broadcast three times a week from 8.30 pm to 10 pm CET, and will consist of excerpts from news reels and of a full entertainment film. Programmes will be changed once a week as at a cinema. Within a short while after the opening of the service the German Broadcasting Company will start providing its own news reel. A suitable sound-recording car with the necessary lighting van has already been ordered. These news reels will be taken and processed in the usual manner, and broadcast each evening under the title 'Mirror of the Day'. Apart from these ordinary news reels use will be made of the daylight television van operating on the intermediate film system to provide red-hot actuality broadcasts of important events. These will be broadcast at the time of happening and will then be repeated in the evening again.
The transportable twin: ultra-short-wave transmitters which were ordered some months ago are nearing completion, and it is hoped to start tests with the second set of high-power transmitters in the late spring. These transmitters are first to be tried out on the Brocken mountain, and modulation will be received from Berlin by wireless link. The transmitters themselves will all be mounted on suitable trucks for transport by road.
The opening of a public high-definition television in Germany at the present moment can be considered as a preliminary run to gather practical data on the actual service-requirements, and programmes will gradually be developed from week to week. On the other hand, the laboratories will be at it full speed ahead to produce a 'Volks-Fernseher' (a people's television set). The quality of the pictures at present transmitted from the Berlin Broadcasting House and received on a Telefunken receiver is exceptionally good, and it now is possible to look in for a full half an hour at a film and really enjoy it.
Naturally 240 lines would be better, but the Germans think quite rightly that. for the small circle who will be able to afford relatively expensive receivers 180 lines has sufficient entertainment value. Today the Press will be generally invited to the opening, and important pronouncements may be expected, especially as a technical German research engineer has only just returned from America where he is said to have investigated systems of electrical scanning.
The check receiver and modulation control panel at Broadcasting House, Berlin. The apparatus was constructed by the Telefunken Company.
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