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previous: Tracy MattThe parascitic ... -- 1/2/2000 8:12 AM

Re: BFDR Parasitic Oscillation

1/3/2000 6:55 AM
Matt	Re: BFDR Parasitic Oscillation Thanks Tracy and everyone else! I tried shielded wire for the intensity pot since the problem ultimately was localized there(with some oscillation also initially occurring in the preamp that was easily resolved). The real problem was the Intensity pot. I'm going to replace it and it should be fixed. I moved the connection going to the amp temporarily to the wiper and the problem was cleaned up. The pot seems to measure fine, but the problem continues when connected per the schematic. Kinda strange. I have tried so many things to get this to work. The thing that kills me is that these amps are so simple inside! I couldn't imagine what was happening! The amp sounds so awesome I'm glad I don't have to modify the circuit to get it back. I think I've learned something here, but also reinforced that parasitic oscillation can be a real pain to find and resolve! Now I can play the thing! Woo hoo! Thanks! Matt

1/3/2000 6:55 AM

Matt

Re: BFDR Parasitic Oscillation

Thanks Tracy and everyone else!

I tried shielded wire for the intensity pot since the problem ultimately was localized there(with some oscillation also initially occurring in the preamp that was easily resolved).

The real problem was the Intensity pot. I'm going to replace it and it should be fixed. I moved the connection going to the amp temporarily to the wiper and the problem was cleaned up. The pot seems to measure fine, but the problem continues when connected per the schematic. Kinda strange.

I have tried so many things to get this to work. The thing that kills me is that these amps are so simple inside! I couldn't imagine what was happening! The amp sounds so awesome I'm glad I don't have to modify the circuit to get it back.

I think I've learned something here, but also reinforced that parasitic oscillation can be a real pain to find and resolve!

Now I can play the thing! Woo hoo!

Thanks!
Matt

Replies:

Bird Dog Maybe there's some crazing or crack... -- 1/3/2000 9:10 AM