Hi All-
I just finished a Blue Breaker. It worked out of the box in my test rig and when I got everything together it makes this loud squealing/screaming noise that modulates with the pots being turned (gets worse or better but still really loud).
I've systematically removed it from the box and basically clipped everything back (except the 3PDT switch) and put it back in the test rig and squeal is still there.
I tested the 3PDT with my ohmeter and it seams fine.
I swapped the TL072 and no change.
Even when the board is switched to bypass I can still hear some faint squeal when I touch the pots (ie. ground them to myself).
I started touching with an audio probe and bad noise comes in at R2.
VRef I measure there and at C9 anode is 4.45 volts.
Any thoughts ?
I just finished a Blue Breaker. It worked out of the box in my test rig and when I got everything together it makes this loud squealing/screaming noise that modulates with the pots being turned (gets worse or better but still really loud).
I've systematically removed it from the box and basically clipped everything back (except the 3PDT switch) and put it back in the test rig and squeal is still there.
I tested the 3PDT with my ohmeter and it seams fine.
I swapped the TL072 and no change.
Even when the board is switched to bypass I can still hear some faint squeal when I touch the pots (ie. ground them to myself).
I started touching with an audio probe and bad noise comes in at R2.
VRef I measure there and at C9 anode is 4.45 volts.
Any thoughts ?
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