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: Andy Fuchs Try replacing the power tube grid w... -- 9/18/2003 1:50 PM View Thread

Re: HELP!! HF oscillation fender silverface

9/18/2003 8:58 PM
Re: HELP!! HF oscillation fender silverface
Thanks to all,  
I have try isolating output jacks, like Tracy has said, but no luck .  
The reverb circuit also had oscillation problems but I fixed them before, when I blackfaced it, I also had put 15k grid stoppers on power tubes, in that moment.  
But this oscillation is located at power amp becouse I inject the signal at PI input ,  
Finally I havent more time and was really tired ,and I opted to put 330pf across PI plates , I dont have time to do what Andy says , but I spend some time before , rerouting grid wires , twist them ...., moving them all around while the oscillation appears on scope but there wasnt any chages on oscillation ,doing that.  
Thanks to all.