Big Briar Etherwave - Barely Audible Output

[Edited from my Reddit post]

I have a Big Briar Etherwave theremin that has almost nonexistent output. The output is definitely not usable; I can barely hear anything besides the 60-cyle hum.

- Antennas - Neither of the two antennas have any effect on volume or pitch
- Pitch knob - Turning the pitch knob does change the pitch
- Volume Trim Pot - Adjusting the volume trim pot does not increase the volume above that low level
- Other Trim Pots - Rotating the other two trim pots does not have any obvious effect

Is this a common problem?  Should I send this to a Moog service center?  Does anyone want to take a (paid) shot at fixing this?

It's a common problem in the sense that all the common problems are likely to result in no output

The most common failure I've seen is that D1 gets zapped by ESD, which definitely causes that symptom, but beyond that it could be lots of things.  If you know anyone who can solder, have them replace D1 and see where that gets you.  Beyond that, anyone who has a scope and can do component level repairs should be able to fix it.

It's a little concerning that you talk about adjusting trimpots, when the Etherwave doesn't have any trimpots.

If you get stuck, PM me.