Эта схема проста и она может быть эффективной. Но он требует тщательной настройки и генератор 220 кГц, которая расстраивается по меньшей мере на 10 кГц от объема антенны.
И есть ошибка: первый конденсатор за "звук из смесителя" не должен быть 4.7pF но 47nF.
With the setting up of the generator, I had no problems because my inductance adjustment. But ratings "sound mixer with" me too surprised. And I replaced the capacitor 1000 pF (which means we must also increase), and reduced the value of the resistor (1mOm).
I've recently had a problem... I made the board, and it worked perfectly. I was then running it with a 9v breadboarded amp circuit. I've now tried to put it in a box, but all I seem to be getting is a high pitched scream, with the very faint sound of the theremin working in the background.
I can send you pictures.
any help would be greatly appreciated, Tha ddeus.
Is the Orientation of various pieces a problem? for example, if I had the main board, with an amp and speaker/ground connection right above it (obviously not interacting with antenna, would that cause problems?
Orientation might be one problem if it leads to magnetical feedback. The material of the housing might be another one, grounding a third one, and stability of the amp circuit, too. I don't have a crystal sphere, thus you might send me pictures and the schematic of the amplifier circuit by email thierry(at)theremin(dot)tf
Another question if you don't mind, how are the theremins in the pictures of the original post (dog one etc.) grounded sufficiently?
The thierrymin circuit is stable enough to work without external grounding, although the sensitivity of the pitch antenna might be slightly reduced. Switching from externally grounded to battery mode requires sometimes a slight retuning of the variable capacitor, though.
It works naturally best when grounded through the shielding of the audio cable if connected to a grounded instrument amplifier.
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