- I bought and installed new tubes for it
The thing has about 12 tubes in it... So even if it doesn't sound great when I'm done, I can use it to heat the studio . I got the tubes from a place in Memphis called TubeDepot.com -- they seemed to have really great prices (like 1/3 what I saw in other sites), sell the same brand of NOS tubes as the others, and they test each one before shipping.
- Am redrawing the schematic from a scanned .pdf file I found on the web.
The scanned schematic was pretty raggy resolution - - I had to guess or derive certain values. But I got it about 2/3 done yesterday. The control circuits (to sample the audio and control compression/expansion) are pretty bizarre looking. It may take a bit of time to sort out just how they work.