> I tried a couple of things very quickly (the first one was
> spectacularly ineffective!). However the following seemed OKish:
> between C10 and Q7 there are 4 resistors - the 2k2 amongst these
> is R24 (the 'bottom one' if you hold the faceplate nearest you);
> swap this for a 5k6 say, which will cut the gain to a third, so
> it won't resonate until the pot is further round. A 4k7 may not
> be enough of a difference, and a 6k8 (I temporarily added a 4k7
> to the 2k2) may restrict the range of frequencies at which it
> will oscillate. Unfortunately it will also reduce the output
> amplitude somewhat.
>
> To do the job 'properly' would mean re-vamping the entire 'gain
> regime' around the loop, which would require considerably more
> thought, and replacing maybe half-a-dozen or so resistors. My
> initial idea was to *double* R5 (the 10k in the middle of the
> only group of 5 resistors, central to the board), but this seemed
> to have little impact, mainly I think because the resonance pot
> is a 'law C' ('rev log'), and so naturally 'all the action' is in
> the first part of its rotation.
>
> Let us know if you have any success with this!
>
> Tim

R5 is the right resistor. It defines the max. resonance. If it's value is
increased the max. resonance (and consequently the position where the self
oscillation starts) should be lowered.

Best wishes
Dieter Doepfer