Pendulum Harmonic Tremolo HELP!

[Travis]

Hi, I build one and when I take off the back of the enclosure and light comes in to the pedal its work perfect.

But if the room is dark or I close the enclosure (dark inside) the volume drops :/

It´s weird

 

[phi1]

With the enclosure off and light in the room, do you get much tremolo effect? The effect works by the ldrs reading the change in light from the LEDs. So I’d think if you get good volume with room lights on, you wouldn’t hear much throbbing. Are the LEDs blinking obviously with the depth knob up?

not having the schematic makes any troubleshooting efforts difficult.

also, do you have the ldrs bent to face the LEDs? (Not sure if this would impact your problem much, without a schematic or any gut shots).

 

[finebyfine]

not having the schematic makes any troubleshooting efforts difficult.

schematic is here: https://forum.pedalpcb.com/threads/missing-build-docs-schematics.3784/page-9#post-52417

 

[phi1]

Cool, I didn’t see that post. So yeah the way the ldrs are positioned makes since that you get more volume with the lights on, but I’m still guessing not much obvious tremolo.

anyway, your comment that ‘the volume drops’ compared to with light coming in wouldn’t necessarily indicate a fault, that would be expected. Can you reach unity with bypass signal volume with the volume knob?

 

[SYLV9ST9R]

also, do you have the ldrs bent to face the LEDs? (Not sure if this would impact your problem much, without a schematic or any gut shots).

I first had the LDR/LED combo pointing at each other in heatshrink (à la "homemade vactrol") but opposite to you I was getting way too much volume and it would distort at higher VOL settings

I ended up placing them the "regular" way (without any covering) I've seen in other builds, and it ended up sounding nicely, with a nice unity volume with just a bit of boost when pushed.

So I think you should try different LDR/LED placement to see if that could solve your issue.

 

[Travis]

I first had the LDR/LED combo pointing at each other in heatshrink (à la "homemade vactrol") but opposite to you I was getting way too much volume and it would distort at higher VOL settings
View attachment 14756
I ended up placing them the "regular" way (without any covering) I've seen in other builds, and it ended up sounding nicely, with a nice unity volume with just a bit of boost when pushed.
View attachment 14757
So I think you should try different LDR/LED placement to see if that could solve your issue.

I did that and it´s SOLVED

 

[Travis]

THANKS guys