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sealed system

In 1924 Ernest Fisk (later Sir Ernest) of AWA - Amalgamated Wireless (Australasia) suggested the introduction of a sealed set system (also known as a sealed receiver) where radio sets could only receive the transmitting service (or services) to which they were licensed. Under this model, the Government would issue a licence to transmit on a given wavelength (or frequency in modern terminology) and oversee the manufacture of receivers locked on that wavelength. The owner of the transmitting licence could then charge the receiver's owner a recurrent fee that would be used to run the station. This was seen as preferable to the British situation where the Government backed a monopolistic service (the British Broadcasting Company as it was then) and collected a single licence fee from each household with a receiver. There appears to have been little attention at the time to a third possible model; that of the licensee charging for advertisements, as was done in the United States.Radio Amateurs were compelled to sign agreements that they would not carry out activities that would challenge this project. Under the legislation being drafted to implement this policy, it would be illegal for the consumer to do unauthorised tampering with the radio.
The following stations operated under the system:

2SB, Sydney, Sydney Broadcasters Ltd, 13 November 1923 (known as 2BL from 1 March 1924);
2FC, Sydney, Farmers & Co Ltd, 8 December 1923;
3AR, Melbourne, Associated Radio Co, 26 January 1924;
3LO, Melbourne, Broadcasting Co of Australia, 13 October 1924;
5MA, Adelaide, Millswood Auto and Radio, April 1924; closed 1925;
6WF, Perth, Westralian Farmers, 4 June 1924.As early as July 1924, the Sealed Set system was declared to be unsuccessful and was replaced by a system of A Class and B Class stations. There were one or two A Class stations in each major market and these were paid for by a listener's licence fee imposed on all listeners-in. The five former Sealed Set stations became A Class stations, and they were soon joined by stations in other State capitals, and by a number of B Class (later commercial stations).

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