Ibanez Wau Wau Fuzz

[Mathias]

Hi all,

I'm repairing an Ibanez Wau Wau Fuzz. I'm not sure as to what is going on. It came in with the battery clip yanked and no sound.
I've traced the issue back to a footswitch and fixed it with some Deoxit. It seems like this pedal has been stored for a long time. It's in otherwise great condition and the circuit seems mint.
When I engage the wha effect it's very dark and muffled, the fuzz section is almost inaudible, no fuzz at all. I remember repairing one a while ago but I'm having a hard time with this one.

Attached is a schematic with voltages measured but CJ. My measurements seem in line with those values.
I wonder if it is just the pot that is worn out or something in the circuitry. Looking for any advice on how to proceed.

Thanks in advance for any advice

 

[radardoug]

What happens when you move the pedal? If it stays the same then the pot is dead.

 

[soapfoot]

Also, try changing the alignment of the rack gear and the pinion on the pot shaft (make sure the pot isn’t using only the low part of its rotation)

 

[Mathias]

What happens when you move the pedal? If it stays the same then the pot is dead.

Also, try changing the alignment of the rack gear and the pinion on the pot shaft (make sure the pot isn’t using only the low part of its rotation)

Sounds like a normal sweep to me, it measures from around 25k to 75k. I'll check up on the rotation offset.

 

[radardoug]

The most effect will be concentrated at the low resistance end. As suggested, reorient the pot to make it work closer to the low resistance end.

 

[Mathias]

I've set up a little audio probe. It comes in clean at C1 into R1.

Clean at the R1, R2 and T1 junction. R1 and R2 measure fine.

After T1 the tone is completely dark. Makes me believe T1 is faulty rather than the pot. It comes in dark at the pot.
And there is some sealing paint on the screw that holds the gear rack in place and looks factory.