Here’s a really small modification for the Electro harmonix’s tube wiggler . I had this pedal few years ago and I was a bit annoyed by the small range of the speed potentiometer. It went to quickly into the ring modulation area. I don’t know if it was a wish of the conceptor or a modification to fit the manufacter available parts. However , I really miss this pedal and try to find one for cheap (even dead by the way), I think it can be improved on several aspects to make a quieter and nicier effect. It is good on its own but improving the sound could be a nice thing.
I breadboarded the LFO and find how to slow it down . For an only one component change , the integrator cap of the LFO (C30) has to be change for a bigger one (bigger = much time to gets charged and discharged = slower oscillation). There’s no proper value it will depend on the maximun and minimun rate you want. 2uF seems to be a good value . Try to find the good one !