[Solved] Cepheid Chorus - only the LEDs work

[zipfool]

This seems like it's going to be tricky to figure out. Bypass works fine, but the 2nd LED stays lit even in bypass. When I engage the switch, both LEDs light up, but I'm not hearing any of the Chorus effect no matter how much I crank the knobs/pots.

I opted to go with the MN3207 / MN3102 IC pairing, but I suspect that my source for these was bogus (seller on EBay). I've tried 4 out of 10 of the pairs they sold me, and I'm getting the same [lack of] effect with all 4 pairs. I could keep trying out the other pairs, but I'm suspicious that all of them will be the same.

Take a look at these photos and LMK if you see anything else suspicious.

There's a few things to this build that are new to me: not sure what the trim pot is supposed to control, and I've never had to solder an onboard jumper to signify which chip combo I bought. Did I do the right thing by putting a bead of solder to connect each of the 2 sets of pads?

If I dial the trim pot up too high, the sound cuts out. Same if dial it too low. Right in the middle and I get clear sound/tone. What does this trim pot do?

 

[music6000]

I could try 12k in those two spots, but I run the risk of wearing out the pads soldering and resoldering.

47k is correct for those 2 Resistors, That was the first thing I noticed way back when you first posted,
It was changed from 12K as the pedal was Louder than Unity when On!

 

[zipfool]

47k is correct for those 2 Resistors, That was the first thing I noticed way back when you first posted,
It was changed from 12K as the pedal was Louder than Unity when On!

Thanks for all the help. I was starting to think I'd never have the sound of the 80's/90's coming through my amp ever again .

I'll post an enclosures and gut shot once I have everything finished up.

 

[zipfool]

Here's a look at the final build:
Chorus of Disapproval

More stuff on Instagram @stompgarage .

 

[Stickman393]

One flew over the cuckoo's nest?

Cause...bird...flip...nevermind.

 

[zipfool]

One flew over the cuckoo's nest?

Cause...bird...flip...nevermind.

 

[fogboundrogue15]

Hello everyone! I've been studying this thread for a bit because I'm running into my own issues with a Cepheid Chorus. If anyone is up for it, I could use some help (it's really my first time troubleshooting a build):

Cepheid Chorus: No Sound or LED Indicator (LFO Works)

I recently started my first PedalPCB build, the Cepheid Chorus. I've built a few overdrive pedals in the past from The Tone Geek, but wanted to try something new. This is also the first time I've had significant issues with a pedal (surprisingly!), so I'm very new to actually troubleshooting...

forum.pedalpcb.com