Bias - Peavey

[Purgasound]

Am I missing something here? I'm a little confused as to how this thread went down the rabbit hole of chasing oscillation. Where is there a problem indicated here other than the bias current being a little high?
I would think the solution for the high bias current would be to alter the bias circuit to reduce bias current or get a new set of tubes that fall within range.
I actually have a VTM60 and a Butcher in the queue for service this weekend. These are generally a breeze to work on. I liked their build method until they started putting heaters on ribbon cables. That's no good.

[The Dude]

See post #21. A different bias current measurement method yielded different results. Bias voltage was measured at -52V. There is no reason, given that voltage that bias current would be high. Altering the bias circuit would not have fixed the problem, which was some sort of undetermined measurement issue.

[Valvehead]

Am I missing something here? I'm a little confused as to how this thread went down the rabbit hole of chasing oscillation. Where is there a problem indicated here other than the bias current being a little high?
I would think the solution for the high bias current would be to alter the bias circuit to reduce bias current or get a new set of tubes that fall within range.
I actually have a VTM60 and a Butcher in the queue for service this weekend. These are generally a breeze to work on. I liked their build method until they started putting heaters on ribbon cables. That's no good.

I have a VTM60 here as well for a cap job !!! Kinda rare amps