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RE: my bias is running away on one side even with the bias backed all the way off on that side!

Posted by Jonesy on July 24, 2020 at 05:46:38:
I couldn't find a service manual online, but looking at the user manual I see that besides the 6 EL84 output tubes per channel, you also have a 6922 signal + EL 84 current source tube. Either of those 2 tubes may impact your bias if defective. In particular the EL84 used as a current source regulator.

Also, if the large black caps are not discharged before testing, they can ruin a DVM. I've had that happen to me. The DVM will no longer work on caps in that high value range. Check to see if your DVM has more than 1 fuse and if either is blown.

Cheers!

Jonesy