Copper plate as antenna?

Errr well I connected the oscilloscope up wrong (not my day), so the stats I quoted are rubbish. It's varying by around 5k, from 18k-13k, which is acceptable. the stability isn't that bad, so it's the hand proximity that I am now interested in. At present it is around 15cm, and I would prefer it to be a little larger. I'll try the cap thing if I have time today.

Apart from the heterodyne doodaa and fine tuning the inputs, my theremin is all working :)

"It's varying by around 5k, from 18k-13k"

those are the listenable frequencies? min & max?

Yeah, on the spectrum analyser the peak varies from around 18k when standing away from the thing to 13k when very nearly touching.

Remember that with the pitch antenna, you want to [i]decrease[/i] the sensitivity. A plate gives you increased sensitivity: with increased sensitivity the notes (pitches) get closer together. You may want to consider use of an antenna rather than a plate for the pitch antenna if possible.

You will notice that the volume antenna is formed into a loop -- this increases the sensitivity of the volume antenna. The rod (pitch side) is designed for linearity rather than for high sensitivity.

It means that a plate is not really adapted for a pitch aerial, but would have a better efficiency as a volume control?

Ok but how do I put an aerial into my guitar? :)

Would it help if the plate was long and thin rather than square?

Sorry bout that... I saw the guitar pic and didn't make the connection.

For the theremin-in-a-guitar application, a plate makes sense. You will have to experiment with component values to get the response that you want.

Keep us posted... interesting project.

[i]-- Kevin[/i]

No problem, when i've got time I start..

I'm also working on a Tannerin (like the Persephone synth), and I don't know which i'm making first.. (guitar's not ready to recieve the theremin)