MXR Dynacomp (CA3080 Rev E. - 2006) noise fix  [SOLVED]

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lolbou
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Post by lolbou »

Hi, just reporting a repair on my 2006 MXR Dynacomp (rev E. with CA3080).

Problem was a "frying bacon" sound. I removed the socketed IC and audioprobed it. The noise was at both pin 2 and 3, so it was before the IC. Noise was also at the base of the first transistor, and up to the positive end of C2 (tantalum capacitor).

I replaced C2 with a good electrolytic, and noise is gone. Easy one, just make sure you add some leaded solder to the RoHS one before desoldering, makes it easier to desolder and clean.
For the record, here's the power supply and LED switching schem, the rest is just the classic schem.
MXR Dynacomp.gif
MXR Dynacomp.gif (266.33 KiB) Viewed 447 times
- Are you a mod or a rocker?
- Uh, no, I'm a mocker.

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