Depths/Abyss LED on-off cutoff only working with Rate pot cranked


New member
I'm having a problem similar to what I've seen on boards with Univibe-type pedal builds, but so far I haven't seen an answer. For the Abyss, the pedal works when Intensity and Rate are all the way up, but when Rate goes down at all, it misses the LED switching threshold and the pulsing stops. After reading about it, I threw in the JC Maillet Offset Mod, (found in the comments on Tagboard Effects) which I swapped in at R25 (on the Q2 B and C). That lets me dial in the brightness but doesn't help with the Rate change issue. It now defaults to Off instead of On when Rate is turned down, but otherwise it only works with Rate cranked.

My somewhat newbie question is, could someone point me to the most likely parts in this schematic that will affect the LED cutoff as it is determined with the Rate knob?

When working it sounds great.