TB moded wah VOX 847A oscillates

[yeeshkul]

Hello guys, i got a VOX  847 (the model with SMD parts on the bottom of PCB and input buffer) for TB installation. Unfortunately the guy has just wrote me that it oscillates in his pedal board. It was working fine here.

I have done this:
1. removed buffer - removed Q1 & SMD resistors from it's coll-base (R12) and emitter (R14, not necessary) - just to cut it off from sucking any DC current
2. removed the SMD part marked L2 and the 100n cap right at the buffer input.
3. Removed the 68k input atten. resistor (R1)
4. Put in a 47k res between the input terminal and the 10n input cap instead of 68k (to even up the wet and dry signal levels).
5. installed LED > + wire connected as at the picture

Here's the picture


Any idea?

[yeeshkul]

Sorted. He brought the unit over and i found out that it produces Seagull sounds while turned off. Not for Gilmour would i be tangled!
3PDT broke down and shorted the signal from a guitar right to the output of the circuit. Brilliant, now i know how to make a simple Seagull Switch.

[yeeshkul]