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Looks more like Tim Escobedo's Harmonic Jerkulator

Glad I could help. The jerkulator is my new favorite dirt. With the guitar volume knob rolled back it gives fantastic cleans. I breadboarded both the jerkulator and the percolator with one switch for selecting the jerkulator vs the percolator, and another switch for selecting Ge/Si/no diode clipping. The jerkulator cuts through better and is much less noisy. The percolator is a little spongier. The perc with Ge clipping at max gain has a nice tone for single notes in the lower register, but otherwise I mostly prefer the jerk. Interestingly, with Ge clipping, the jerk is louder than the perc. I expected them to be the same volume because of the hard limiting, but I think maybe the jerk just has more mids, so averaged over the audible spectrum it has more energy. With Si clipping, the jerk is slightly louder than the perc, but the difference is less drastic.

With the jerk, I can get feedback and/or nearly infinite sustain with my amp turned down low enough for my 1-year-old to sleep in the same room. Amazing.

FYI, I had to put a 10k resistor inline with the input to keep it from humming when I turned the guitar volume all the way down. I also left out the 1k between the gain pot and ground, bumped the 22uF up to 44uF (I used tantalum for that, which supposedly sounds better than electrolytic here, but I didn't A/B it), and added a 1n5 in parallel with the 22k to ground to protect against RF.

I have a vero layout for the combined perc & jerk, if anyone is interested. (Fair warning: contains some SMD.)