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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
oskar
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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.  
Oskar.