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

Forum dedicated to helping people debug and troubleshoot non-functional pedals or builds. Please use an clear and informative title, indicating circuit and basic problem. Don't forget to mark the issue as fixed if this is the case.
Post Reply
User avatar
lolbou
Old Solderhand
Information
Posts: 2617
Joined: 18 Nov 2008, 21:38
Has thanked: 307 times
Been thanked: 224 times

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 425 times
- Are you a mod or a rocker?
- Uh, no, I'm a mocker.

Post Reply