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previous: Gil Ayan OK, if tunring up the lower end cau... -- 12/29/1999 7:20 AM view thread

Re: Oscillation Problem

12/30/1999 12:34 AM
Mike T
Re: Oscillation Problem
Gil..thanks. For decoupling the power supply, you mean beyond the standard filter caps? By each stage, do you mean each b+ lead coming from the FCs? What I did so far was this, with no improvement: changed the .1 and .047 tone caps to both .02, changed the coupling cap out of the preamp from .02 to .001, the coupling cap at the input of the driver is already .001, changed both .1s from the driver to the grids of the power tubes to .02. But little improvement. Could it be perhaps that one of the resisters between the FCs has failed? I havn't taken the cover off them for inspection for quite awhile, but in the last incarnation of this amp, a quasi Marshall 1987, they were fine. I think something has failed somewhere, maybe I should just shotgun the whole thing and start over...

Gil Ayan q{Gil..thanks. For decoupling the ... -- 12/30/1999 7:12 PM