help needed with my noisey Frequency Analizer

[foxfire]

i got it as a project, and it certainly is turning out to be one. it wasn't working when i got it. i quickly got it working, and replaced all the electrolytic caps. i noticed a high pitch squeal, and promptly wrecked the AD533jh in my hunt for the squeal. i replaced that today. the squeal is still there, and it's there whether the pedal is in "bypass" or not since the signal is always going through the pedal.

so to recap, i've replaced all the electrolytic caps, checked all the voltages, replaced the AD533jh (had no effect on the squeal), checked most of the caps and resistors for drift, and scratched my head an awful lot. oh and with a probe i am hearing the squeal on pins 2 and 6 of the 741 which is the which is the first component the signal hits. i tried replacing that to no avail.

i'm thinking it is coming from the power supply, and unfortunately i don't have a spare power supply to try it with. my fear is that the SG5401n is the culprit...

[Taylor]

The squeal is the same pitch regardless of the Shift and Fine settings?

[foxfire]

Yes...

[foxfire]

it seems i may not have a problem after all. i should have tried this sooner, but i simply tried the pedal in my shop (that has it's own sub panel with a solid ground) and it was quiet as could be...it'll quite nice if i don't have to buy a new SG5401n.