TC Electronic Afterglow Chorus repair

[Yazoo]

I bought a for parts Afterglow chorus and have been trying to repair it. Firstly, the footswitch wasn't working (again a problem with their footswitches!). The problem was that the microswitch on the pcb wasn't being depressed enough. I fitted a 1mm washer and that solved that problem. The build quality is good but this is the third TC Electronics pedal I have bought with a footswitch problem.

Secondly, the V3207 BBD wasn't passing signal. I removed it, put in a socket and borrowed an MN3207 from another pedal. It worked but was heavily distorted. There is no trimpot for bias adjustment on the board so I put the chip on a breadboard and stuck a 100N capacitor in series with the MN3207 input to block DC and used a potentiometer to dial in the DC bias separately.

I have now got it working. The bias on the original pcb must be hard wired and a lot of the pcb is surface mount, so not easy to rebias. What I might do is add a daughter-board to fit in the socket and replicate my breadboard circuit on it.

Has anybody else come across this? I couldn't find a trace of the circuit online.