'94 Evil Twin issues

[LarBal]

One of these came in with the issue of "ticking/motorboating after an hour"
I played it for a bit and it sounds great, all 3 channels.

I put it on the bench and now the two higher gain channels(pushed clean and high gain) arent functioning correctly.
They each have a gain, and (master)volume setup. The volume is not doing anything, like its stuck on 10. This is happening for both channels. The Gain pot now acts like a master, and squeals past 3 on the high gain channel and of course is silly loud.
Also, the tone controls arent working on either channel, but the mid pots and gains/volumes are all showing continuity to ground from the 3rd lug.

I've cleaned evry pot, and even replaced the high gain vol pot R39, and replaced all preamp tubes. Nothin.

Any ideas?
edit :also signal is still coming out of the speakers even when the pots are at zero. This is for all channels.


Fender-94-Twin-Schematic.pdf

[xtian]

Did you measure resistance of those volume pots? Did you measure resistance from pots to chassis ground? If the whole tone/volume control PCB lost connection to ground, that might explain the mystery.

[LarBal]

Yep, all 3rd legs of the pots are connected to ground(rather the ones that should be), and show continuity. The whole pot board grounds to that chassis via 1 geen wire , like a HRD or the like.
I didn't even do anything between playing it and putting on the bench, so I'm not sure what happened. Again, the gain pots are functioning fine, except for still passing signal when at zero, so yea its gotta be a ground issue right?
But I even took gator clips at manually grounded things, and no change

[LarBal]

I'm back on this...looks like the scheme didn't post. Here's a link https://www.thetubestore.com/lib/the...-Schematic.pdf