Tractor Beam passing signal but no effect (even with trimpot adjustment)

[wizestwizard]

I just finished building the Tractor Beam, but can't get any phasing no matter what I do with the JFET trimmer. The level trimmer also has no effect on the output, nor do any of the external pots or switches. All of the voltages match up to the ones in the build doc more or less (a few are a little low, but not crazy), I tested the voltages on the switching board prior to wiring and they're also good. The one weird thing is the voltages on the gates of the JFETs don't vary unless the trimpot is adjusted (they don't vary with just time the way the ones on the ICs do). I bought a quad matched set of JFETs and checked them myself, so that's not the answer. I've attached pictures, any suggestions are welcome. Thanks!

[Aentons]

What going on with your board up above the IC and below the trim pots? It seems to look like shattered glass.

Other than that, have you tried pressing in on the jfets while you are listening? Sometimes sockets are not the greatest

[jimilee]

Is it safe to assume you used 5952s? Got any pictures of the back side and any voltages?


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[wizestwizard]

I did use 5952s, the voltages on the JFET gates change based on the trimmer, the source and drain are both 0, all of the voltages match the ones at the end of the build docs. Here's a pic of the solder side though it's a tight board so idk how helpful it'll be

The stuff near the trimmers is a few straybdog hairs lol.

I'll try pressing on the JFETs, but they're getting power so I don't think that's it

[wizestwizard]

Even if it's not phasing, I'm surprised that none of the controls have any effect, especially the internal level trimmer. It almost seems like it's being bypassed no matter if the pedal is on or off, though the led comes on when the switch is engaged, which I would think coincides with the signal being routed through the effect instead of bypass. Any thoughts?

[Aentons]

So if power is fine, then follow the audio path. If you have clean signal coming out of the switch board, use an audio probe starting at the effect board and see if it stops at some point

[wizestwizard]

There's clean signal all the way out of the effect board, but no controls change the sound of the signal at the output lol

[wizestwizard]

The schematic is also terrible on the build doc so following the audio signal would be pretty difficult lol

[Aentons]

There's clean signal all the way out of the effect board, but no controls change the sound of the signal at the output lol

I was just thinking that if there is a solder bridge or something is touching or shorted somewhere in the signal path then it could be bypassing the effects and sending the clean out

[wizestwizard]

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

[Aentons]

The schematic is also terrible on the build doc so following the audio signal would be pretty difficult lol

You could use page 2 that shows the actual board traces

[Aentons]

You could even start the audio probe with output pins 1, 7,8,14 of the 2074 since that's where the phasing occurs

[wizestwizard]

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

[wizestwizard]

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

[Bio77]

Does that mean if you hold the switch down the effect will work?