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Reverb hum

5/19/2000 2:43 AM
Jim Martin	Reverb hum Just Blackfaced a 69 Bandmaster Reverb AA768. Replaced chocolate drops, ceramic caps, filter caps, etc. Works and sounds great except for nasty reverb hum. Sounds like a single coil hum. When the reverb knob is all the way down, no hum. As it is turned up, the hum grows louder. This hum happens whether or not the footswitch or reverb unit is plugged in! When the reverb unit is plugged in, I get reverb and hum together. When I touch, or come close to, the .002 cap on the reverb output jack, the hum gets a lot louder. Replaced tubes, checked voltages, all are ok. The gound connection checks out. I'm stumped. Thanks for any suggestions.

5/19/2000 2:43 AM

Jim Martin

Reverb hum

Just Blackfaced a 69 Bandmaster Reverb AA768. Replaced chocolate drops, ceramic caps, filter caps, etc. Works and sounds great except for nasty reverb hum. Sounds like a single coil hum. When the reverb knob is all the way down, no hum. As it is turned up, the hum grows louder. This hum happens whether or not the footswitch or reverb unit is plugged in! When the reverb unit is plugged in, I get reverb and hum together. When I touch, or come close to, the .002 cap on the reverb output jack, the hum gets a lot louder. Replaced tubes, checked voltages, all are ok. The gound connection checks out. I'm stumped.

Thanks for any suggestions.

Replies:

DonJ Jim, Check your cables to the rever... -- 5/19/2000 2:55 AM
Eric Eisenhower I just restored a Gibson Minuteman ... -- 5/19/2000 3:27 AM
Tom Had the same problem in a '71 BMR,<... -- 5/20/2000 4:18 PM
JC I'm new here, but once had a simila... -- 5/20/2000 4:37 PM
JoeArthur If the reverb also seems weak and t... -- 5/20/2000 8:13 PM