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previous: GFR Take a look at www.aikenamp... -- 1/12/2000 4:22 PM

Re: No Plate Resistors ??????????

1/13/2000 7:09 AM
Steve	Re: No Plate Resistors ?????????? Thanks GFR for a kind response to a question that proves two things: First: Don't inhale those solder fumes(even though they smell soooo good!) Second: Don't post questions at 4:00AM! My brain wasn't working too well. The thing that has got me going on this amp is , the bias on one pair of power tubes drops from -55v to -34v and then keeps on dropping. Of course, the plates start to glow. It is almost as if it is a timed thing. Power switch on , -55 on all four tubes. Standby on, all O.K. wait about 40 seconds, I hear a "punk" in the speaker and the bias drops to -34v on the one pair of tubes(same phase). Go back on standby, bias stays the same. Turn power switch off and right back on, bias back to -55v all four tubes. It doesn't seem to be a thermal related problem, since it copmes back so quickly. Maybe the EVH "Brown" sound refers to the graphics on those two tubes! Thanks for any help, Steve

1/13/2000 7:09 AM

Steve

Re: No Plate Resistors ??????????

Thanks GFR for a kind response to a question that proves two things: First: Don't inhale those solder fumes(even though they smell soooo good!) Second: Don't post questions at 4:00AM! My brain wasn't working too well.
The thing that has got me going on this amp is , the bias on one pair of power tubes drops from -55v to -34v and then keeps on dropping. Of course, the plates start to glow.
It is almost as if it is a timed thing. Power switch on , -55 on all four tubes. Standby on, all O.K. wait about 40 seconds, I hear a "punk" in the speaker and the bias drops to -34v on the one pair of tubes(same phase). Go back on standby, bias stays the same. Turn power switch off and right back on, bias back to -55v all four tubes. It doesn't seem to be a thermal related problem, since it copmes back so quickly.
Maybe the EVH "Brown" sound refers to the graphics on those two tubes!
Thanks for any help,
Steve

Replies:

A.S You might have a leaking coupling c... -- 1/13/2000 8:55 AM