LFO issue on Tremulus Lune PCBs

[patrick398]

Hello all, i put together a PCB for a 3 knob Tremulus Lune but the LFO doesn't seem to be functioning. The LED in the opto is always on but i can vary the brightness with the depth knob. Decreasing the brightness reduces volume of signal as expected. So it's all functioning, the LFO just won't wobble. I drew a schematic of a 3 knob version of the tremulus lune and i'm thinking i've made a mistake...though i can't see it.

LFO section:


I spotted one mistake i made already. Compared to all the schems i have i was missing a 220k from Shape/Smoothness lug 3 to pin 2 of the tl062. I've added that in but still nothing. I'm totally stumped. Any help would be hugely appreciated as always

TL062 voltages:
1 - 4.58v
2 - 4.75v
3 - 4.5v
4 - 0v
5 - 4.53v
6 - 4.59v
7 - 4.58v
8 - 8.81v

[Kipper4]

Think you are missing a 220k nfb loop.

Link to fuzz central.
Minus the fine and spacing.

https://fuzzcentral.ssguitar.com/tremulus.php

[patrick398]

Thanks for the reply Rich, I think that is the one I caught, the 220k from smooth lug 3 to pin 2 of opamp, that's the negative feedback right? I have tacked that on and still get nothing

[Kipper4]

Drop C3

[patrick398]

Drop C3

You're my hero Rich! Nailed it. I put that cap across the voltage divider because i though it might help with noise on the LFO, i'm guessing that reference voltage needs to be able to move around though? And the cap gives it a constant steady voltage so the LFO doesn't wobble?

[Kipper4]

Nice one Patrick