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Vintage threads from the first ten years
| previous: Derrick First, is the tremolo on a separate... -- 3/25/1998 10:48 AM |  |
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Re: Marshall Amps/Gospel Radio
 3/25/1998 11:13 AM |
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Ted Breaux | Re: Marshall Amps/Gospel Radio The trem section is at the end of the mother tag board. The trem uses a PNP transistor (I suppose as an oscillator), a 12AX7, and appears to alter the bias of a preamp tube (from memory). The phenomenon occurs in different rooms, and is audible only when the volume on the trem channel (Ch 2) is turned up with cable in. I will short the cable jack pins. If that fixes it, I will decouple the cable. If not, I am going to check all solder joints and grounding. I may have to shield some runs of wire in the preamp as well. I will let you all know how turns out. Hmmm...this gives me an idea.....if I service the amp of someone I am not too fond of, I'll just build a crystal radio into the backlside of the tag board, and wire the output directly into the preamp. That should be fun to diagnose! Ted B. |
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| stephen delft Ted, |