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The radio was built in what looks like a dark oak chest of drawers from which the bottom drawer has been removed. The centre drawer has been taken out and its front panel cut and refitted with a centre-mounted loudspeaker, behind which was presumably mounted the power supply, which has long since disappeared. The top drawer has been modified by removing its sides and rear panel and its base then covered with a sheet of copper to act at a baseboard. To this are fitted the components including the valve-holders. Tucked in behind the speaker I found a letter and various documents including a hand-drawn circuit diagram, data sheets for the commercial coils and valves etc. The set was said to have been made by a Mr Robert Laurence of St.Catherines Grove, Lincoln and was apparently given by a Mrs Doris Mackenzie of York to Lincoln College? Presumably from there it eventually found its way to Birketts. The set is a TRF type and uses a collection of early "mains" valves with indirectly heated filaments and a number of heavy, metal-cased, Wearite coils. The tuning condenser is a three-gang type with a very smooth slow motion tuning dial calibrated 200 to 550 metes and 700 to 1900 metres together with a logging scale. The set hadn't been touched for donkey's years and was thick with dust. After hoovering (I always use blow rather than suck because this works better- out of doors of course!) and once the bits were visible, I discovered the original construction was more hurried than reliable and I found numerous minor reasons why it would not have performed well. Also, one of the interstage transformers was open-circuit which is often a problem in sets of this age, probably because the very thin copper wire of the high impedance windings, in contact with the iron terminals and a touch of damp results in electrolytic action, corroding the copper wire. The valve line-up is as follows:- RF amplifier: Standard Super Valve, VM/SG AC Detector: Standard Super Valve, Detector AC LF amplifier: Mazda AC/PEN The first two are thoughtfully marked 4v 200v/100v and 4v 200v respectively
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