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previous: Carl I just did some work on my 1965 BF ... -- 6/14/2000 8:45 PM

Re: Help: my DR squeals when I turn the reverb knob

6/15/2000 2:01 AM
Ray Ivers	Re: Help: my DR squeals when I turn the reverb knob Carl, Is there still a 220K resistor from the reverb return jack (Fender calls it 'reverb output') to ground? Maybe it had broken off, and there was just the remains of one of its leads, that you snipped off? If it's missing, this resistor should be replaced before checking anything else. Also - if one of the new replacement filter caps was bad or is failing to make contact with the circuitry, you could get this same symptom due to interstage coupling. Fender hangs 6 (!) gain stages off this one power supply node (16 uF, 450 volt cap) - I would check it out right away, and maybe consider going up to a 20 or 30 uF unit, or even higher. Ray Ivers R.A.G.E. Electronics

6/15/2000 2:01 AM

Ray Ivers

Re: Help: my DR squeals when I turn the reverb knob

Carl,

Is there still a 220K resistor from the reverb return jack (Fender calls it 'reverb output') to ground? Maybe it had broken off, and there was just the remains of one of its leads, that you snipped off? If it's missing, this resistor should be replaced before checking anything else.

Also - if one of the new replacement filter caps was bad or is failing to make contact with the circuitry, you could get this same symptom due to interstage coupling. Fender hangs 6 (!) gain stages off this one power supply node (16 uF, 450 volt cap) - I would check it out right away, and maybe consider going up to a 20 or 30 uF unit, or even higher.

Ray Ivers
R.A.G.E. Electronics

Replies:

Richie{~}==::: Carl: This does sound like the cap ... -- 6/15/2000 3:06 AM