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I am starting on the design for a Twin Peaks enclosure after finishing populating the drolo board.  The delyk board is TINY!  The artwork here looks great too. 

Did you find the roll-your-own Vactrols to your liking in this build?  Just Tayda LDRs and red LEDs?  I ask because I have yet to put that component on my board and was planning to go in the same direction.

I used white LEDs with GL5516 LDRs from eBay (on the recommendation of David Rolo). They are cheap and work great. Solder two legs of the LDRs together for each vactrol. Here's a quick demo of how they sound in the cherry pie:

https://m.youtube.com/watch?v=607hTfnESwY

Looks superb!

I got a nice surprise when voltage starving the circuit:

https://youtu.be/OvmXb8X2sN4

So my question is what's causing it to tremolo? As you can hear in the video, it kicks in when the level drops below a certain point. It's quite a fun extra to an already great superfuzz! The rate is also somewhat adjustable via the voltage starve pot (5kB).

I didn't have the NTE109 diodes the circuit uses so instead I put a couple of 1N34A in.

Thanks for the help Felix... I redid some of the ground wires and everything is hunky dory now 

I have some spare time tomorrow so I'll check the continuity on the switch. I'm fairly sure all the grounds are connected where they should be, but I see your point about it being an issue with a bad ground. I'll try reflowing the connections and see what happens. Keep you posted.

And thanks very much for the help too... this seems like an amazing tremolo so it would be great to get it sorted out. 

Right! That's good to know, thanks Felix. I suspect it's a bad switch as the other end of that ground wire just connects to the output jack sleeve and from there to the input jack sleeve.

The only other possibility I can suggest (and it's a slim one) is I'm using one of David's prototype PCBs, which has an extra ground pad for the tempo indicator LED. I noticed on the build document for the project that this pad is missing from the finished PCB. The tempo LED is instead grounded directly to the momentary switch. I doubt it makes much difference though. The pedal seems to work fine, so I guess it's a crappy 3pdt.

I did the Madbean method for the wiring...

Ok... So I have 7.5v on lug 2 of the 3pdt (the ground). And when I switch the 3pdt on it goes to 0v. Hmmm, does that mean a dodgy switch? I've tried reflowing the solder on all the ground connections on the 3pdt.

And the LED itself seems ok. Can I conclude that the 3pdt is to blame?

https://youtu.be/0tlCPDXwD2I

Spoke too soon.
The LED is reducing the voltage from 9.6v to 7.5v on lug 1 on the 3pdt. It doesn't light up though. Could it be a bad 3pdt? It's not a bad connection if I'm getting voltage from DC jack to lug 1, is it?

Here's a video of the problem:

https://youtu.be/JGAyb53vpFA

Ah, it's working! I had a last ditch solder reflow. Phew.

I'm stumped by a bizarre problem with an LED...

I've built David Rolo's Twin Peaks tremolo. It sounds great but the LED for the bypass foot switch does not come on. Everything seems to be working ok with the pedal itself... Sounds great and looking inside, the home-rolled vactrols and tap tempo LED flash in time. The bypass LED however does not light up. I swapped the CLR down from 6k8 to 3k9 and measured the voltage: I'm getting 9v on the wire before the LED and 7.5v on lug 1 on the 3PDT (so the LED seems to be doing it's thing) but the LED just doesn't light up. I've tried three different LEDs, reflowed the solder at all relevant points, and the voltages would surely read 0v on the 3PDT if I had the LED connected the wrong way around, or if there's a bad solder joint somewhere.

Urgh. Any ideas guys? Never had a problem like this before...

Sounds great and looks very cool too. I'm going to build one.

Thanks for sharing how you did it. I've got some left over LDRs so this will be fun to try on different circuits. Cheers. 

I built a Mini using the vero layout at Tagboards but it looks a hideous mess in comparison to this. Great work, Cody!