Roland Bee Gee AF-60 problem.

[richlespaul]

I just getting into this pedal thing so be nice. Just got hold of an old Roland Bee Gee AF-60 but the thing is making a noise a bit like an lead plugged into an amp but not plugged into a guitar. The tone of it changes when I adjust the tone pot and the noise increases with volume adjustment. The pedal switches off and on ok with the guitar tone getting nice and fuzzed when on.

I have got it apart and checked it out, wiggled everything, checked for dry joints etc but nothing really changes. My next port of call is to change the electrolytic caps, does this sound about right?

Help please..  ::

[aron]

Does it make this sound running off the battery? If so, I would suspect some sort of grounding problem.  Does the sound happen both when the effect is switched on and off?

[richlespaul]

Battery power for sure, perfect when switched off noisy when on

[R.G.]

It is quite difficult to read the schematic you posted. It may have been down-resolutioned by the posting process. Is there a better one?

But yes, the next step is to change out all the electros, per the advice in the Guitar Effects Debugging Page at GEO.
Edit:
Never mind, the pic in its original URL is fine, it just doesn't display here well.

I would check to see if there's a missing ground wire from the board to the enclosure.
End Edit.

[alex frias]

Just copy it to something like Paint on Windows or any other aplication in other plataforms.

[Mark Hammer]

Nah.  Right click on the image, and select View Image.  Then, when you see the + sign on the cursor, click again.  Clear as day.  Plain as the grey hair on both our heads.

[richlespaul]

Thanks..
http://eu11.stripper.jp/pulcino/blog/images/BeeGee.gif

[Gus]

Measuring the voltage at the collectors of the transistors and the output pin of the opamp can help find the place to look.

Did you measure the switch connections with a meter set to ohms?  Maybe the connection for the effect has a problem.

[richlespaul]

Measuring the voltage at the collectors of the transistors and the output pin of the opamp can help find the place to look.

Did you measure the switch connections with a meter set to ohms?  Maybe the connection for the effect has a problem.

No idea about this one I afraid.

I have discovered when playing the noise goes but returns once I stop? 

[richlespaul]

OK changed all the electrolytic caps, some improvement I reckon but still not right.. Whats next

[richlespaul]

Changed all caps now but still no joy. I have noticed if I reduce the input signal (guitar volume almost off) the noise stops.