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1939 __ Utility Radio
Comment : The Utility Radio was an all-mains 4-valve domestic superhet radio receiver, manufactured in Great Britain during the 1939-45 World War. When war broke out in 1939 all the British radio manufacturers switched to producing a wide range of military radio equipment for the armed forces. Perhaps the most famous product was the R1155 communications receiver used by the RAF. After a few years there was a shortage of radio repairmen as they had all been called up to maintain vital radio and radar equipment. Similarly there was a shortage of spare parts, particularly valves, as all production was for the services. This meant it was very difficult to get a radio repaired and with no new sets available there was a desperate need to overcome the problem. The Government solved this by arranging for all radio manufacturers to produce a standard design with as few components as possible. Earlier the Government had introduced the 'Utility' brand to ensure that all clothing, which was rationed, was produced to a reasonable quality standard as prior to its introduction a lot of shoddy goods had appeared on the market. So the 'Utility' brand was adopted for this wartime radio. The only significant shortcoming compared with pre-war radios was the absence of a long wave band and a simple tuning dial. This resulted in fewer tuning circuits and the absence of a wave-change switch. The tuning dial was a very crude affair compared with pre-war when the tuning dial was a work of art displaying dozens of stations throughout Europe. Dials were marked in metres with only the 'Home' and 'Forces' stations identified. The sets used a four-valve superhet circuit with an audio output of 4 watts at 10% total harmonic distortion; they performed as well as many pre-war sets. The valve complement consisted of a triode-hexode frequency changer, a variable-μ RF pentode IF amplifier and a high slope output pentode. A copper oxide diode was used for demodulation and the HT line was derived from a full wave rectifier. All valves were on International Octal sockets apart from the rectifier which was on a British 4-pin base. There were minor variations between set makers; for instance Philips used IF transformers with adjustable ferrite cores (so-called slug tuning) rather than the conventional trimmer capacitors. The general public were unable to tell the manufacturer of a particular set although each manufacturer used a code to identify themselves to dealers. For some curious reason the valves carried cryptic designations such as 274. They were produced by valve makers such as Mullard, MOV, Cossor, Mazda and Brimar. Dealers, knowing the maker of a set and which valve manufacturer that maker used, could easily deduce which pre-war types these were. The set could be seen as the British equivalent of the German Peoples' Receiver (Volksempfänger). (Compiled from various sources)
Urls : http://www.thevalvepage.com/radios/wartime/mains/warmains.htm (last visited )

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