Tube Amps / Music Electronics
For current discussions, please visit Music Electronics Forum. New: view Recent Searches.
New: visit Schematic Hell!
The sunn still shines online!

Listen to great tunes streaming live right now!

ampage archive

Vintage threads from the first ten years

Search for:  Mode:  
previous: TubeHead still going crazy over this weird p... -- 9/8/1999 3:35 AM View Thread

Re: Bass pot causes major prob. in 66 Pro-Rev

9/8/1999 1:03 PM
J FletcherRe: Bass pot causes major prob. in 66 Pro-Rev
Sounds to me like there's some motorboating going on, due to poor decoupling in the supply, as you suspect, or perhaps some positive feedback due to stray capacitance or resistance between components. I'd try moving some of the leads or components to try and get some seperation, physically, between them, as the problem is occuring. Sometimes there's a problem with the fibreboard card underneath the circuit card, becoming "live", that is I've seen them become microphonic and cause weird problems. Same for the circuit card. Just a couple of guesses..Jerry

TubeHead Re: Bass pot causes major prob - no More! -- 9/9/1999 12:57 AM