MOTM

The PAIA theremin, IMO, is not engineered very well so you'll probably need to do battle with the beast. RF circuits when first powered can be real tricky to align depending on the initial settings of the coils and component tolerances. Some units can be so misaligned that they'll seem dead. A scope helps greatly in this situation. The debug it, try to observe the freq from just one oscillator by adjusting the coils for just that oscillator. Repeat the operation for the other oscillator. And finally using the scope make sure the frequencies for both oscillators are as close to possible as you can get. At this point, assuming there's not bad parts or construction errors, it should make some sound.

John Speth
Molectron Detector, Inc.
http://www.molectron.com
mailto:johns@...