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One of the resistors (3k3 next to the bipolar cap to be exact) had somehow broken off from the lead right at the board. Replaced it, works great now!

That was my hope but since it's been a month I kinda lost hope. I just tried pulling and resoldering the transistors, checked them after I pulled them to make sure they were still OK and they are. Just fought with the bias trimmer again as well after putting them back in, still same issue. I feel like it's gotta be one of the components in the LFO but between my lack of knowledge and the crazy schematic idk where to even start lol

Just finished the Junk Trunk and it passes signal and I can hear it don't some envelope filter type things, but there's a MASSIVE volume drop with the effect on vs when bypassed. I've checked all voltages against the build doc and they match up, so I'm not sure what the issue could be. Any help is appreciated! Thanks!

Anyone have any additional thoughts? Lol

Switching the LM358 didn't help unfortunately. No idea what's going on.

That's my thought too, I just couldn't figure out where to begin troubleshooting because 1) I'm still somewhat new to building (I've built a bunch of pedals, ~50, but I still don't understand all the specifics of more complex effects like those that are time based) and 2) the schematic for this is particularly hard to read, plus nowhere in the build doc does it show the component numbers (which are on the schematic) matched up to which component they are lol. I didn't remove the LM358 but I can pull it out and check it /swap it for another

Yes, when moving the JFET trimmer, there is a point in the sweep where you can hear the frequency/resonance changing, however, it doesn't phase on its own over time. Moving the "center" control also has this effect - essentially, you can hear phasing when manually turning either the "center" control or over a certain part of the JFET bias trimmer, but it will not modulate on its own over time, leading me to believe it's an issue with the LFO. When the JFETs are in the sweep spot on the trimmer, it acts like a fixed resonant filter.

Here are the pics, it's such a congested board that I don't think they'll be very helpful though lol. I'm guessing it's a dead component at this point rather than a soldering issue but any suggestions are appreciated

Sorry, I just saw this, I'm not sure why I didn't get a notification lol. I can show pics but I don't think they'll be helpful - all of the voltages are correct now (the V- wire had somehow come disconnected which is what was causing the weird readings before) , the parts are in the right places and orientations. It was working properly, I removed the transistors and sockets and soldered the transistors back in and now it's just behaving strangely. There's no modulation, which leads me to believe it's an issue with the LFO. By turning the "center" knob, it manually phases, sweeping the resonant frequency, and by turning the bias trimpot there's a point at which this also happens. I can't make heads or tails of the messy schematic to figure out where to look to pinpoint the LFO issue though, that's the major problem I'm having at this point. Something is causing the LFO not to oscillate lol

I had the tractor beam working, but some of the transistor sockets were a little loose, so I desoldered them and soldered in the transistors. Now the effect no longer sweeps, it's just behaving like a fixed resonant filter. Some of the voltages are off now too : pin 7 of the OPA is about - 3.2V instead of 0 and while the source voltage of the JFETs is 0, the drain is sitting at around half a volt. Power in from the switching board is fine (+/-7.5 ish V). The schematic for this thing is a nightmare, so I was curious if anyone had any thoughts on what might have happened? No solder bridges anywhere and the only parts I changed were pulling out the sockets and putting in the transistors. Thanks in advance!

According to the switching board doc, that doesn't seem to be the case?

"When the relay is in bypass-mode, pin7 of the PIC puts out a continuous 5v which is applied to the gate of
Q1. This grounds the power rail created by R2 to turn off the bypass LED by using the mosfet as a switch.
IOW, the nominal state for the LED is on and the mosfet "interrupts" (grounds) the power to the LED on
bypass. The 20k trimmer is for the user to control their preferred LED brightness."

Either way, I had the wrong relays and the board was behaving as if it was always in bypass, so I pulled the relays out of the board and am going to put the latching ones in

I'm not entirely sure, this is only the second pedal I've built with relay switching instead of just the standard 3pdt. What's strange to me is that when I press the switch, the status LED stays on, but it's very obvious that the signal path is in bypass no matter what. I ordered the right relays (Mouser is out of them, which is probably how I ended up ordering the wrong ones lol) so I'm just going to switch them out. Hopefully I can pull the old ones out of the boards though, I also have a mini mu in the works that I haven't finished yet lol

I think I found the issue - I accidentally got non latching relays 🙃😑

So once I dug out the audio probe, it looks like my initial suspicion was right - the entire effect board is being bypassed for some reason. I tested the switching board before wiring it, I can hear the relay click and the LED comes on when the switch is pressed, so I'm not sure what could be going wrong. There aren't any solder bridges on the switching board but the signal is going straight through from input to output

I was thinking that too, I thought I checked everything but I'll look again