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Old 26th Feb 2020, 11:05 am   #11
turretslug
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Join Date: Nov 2011
Location: Surrey, UK.
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Default Re: Professor Theremin advert.

Does anyone know if Theremin's original circuit is in the open? There are any number of "Theremin-alike" circuits on the 'net involving valves, BJTs. FETs, ICs, but I believe (this is sketchy!) that the original used a saturable reactor to control the filament current of a valve amplifying/buffering the heterodyne product and hence output level. Considering this mechanism, not to mention the available technology of the early '20s, I think this would need to have been a bright emitter type?
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