Aion Refractor Gain potentiometer malfunction

[ultimo]

Dear DIY community.

I am a complete beginner to building pedals, it is a hobby sort-of-a-thing to me, but I really enjoyed a simple fuzz circuit build so far.
I decided to try one of the pre-made pcb kits, and i choose the Aion Refractor. My soldering joint don't look nice, but i think there is a connection throughout the pcb.
My problem is with the gain (dual gang 100k) potentiometer. When I plug in my guitar and run it through the amp, the tone and the volume potmeters seem to work ok.

However the gain potmeter seems to be "unstable". I get the biggest signal to my amp when its completely turned to zero and as I would gradually increase the amount of gain the signal weakens, gets quieter and when its completely maxed, it is just a tiny bit louder. And there seems to be no gain, no clipping with the guitar sound.

Voltage at the gain potmeter is 4,51V.

i measured the IC voltages at 9,02V DCo and this is what I saw:

IC1
-   1: 4,51V
-   2: 4,51V
-   3: drifts from 3,5V to 2,88V
-   4: 0V
-   5: 0V
-   6: 4,51V
-   7: 4,49v
-   8: 9,01V

IC2
-   1: 4,51V
-   2: 4,51V
-   3: 4,50V
-   4: -8,74V
-   5: 4,51V
-   6: 4,51V
-   7: 4,51V
-   8: 16,43V

IC3
-   1: 9,02V
-   2: 4,59V
-   3: 0V
-   4: -4,29V
-   5: -8,73V
-   6: 4,27V
-   7: 5,69V
-   8: 9,02V

which when comapered with the manufacturers building instructions and troubleshooting (available at their site), seem to me ok with my voltage (they measured the values at 9,86V)

Any suggestions? I was very careful to solder the tantalum cap in the correct direction.

I bet it is some rookie mistake, just would love to have some input, what to look for. I dont really understand what is wrong with the potmeters function.

Thank you so much for any answer.

[aion]

Since the IC voltages all line up, photos would be the next step. The good news is that it's confined to one specific area, so you've most likely got either a solder bridge or a cold joint not making a connection. I'd start by reflowing all the solder joints, which will usually catch both cold joints and inadvertent bridges.

Schematic here for reference if anyone else jumps in:
https://aionfx.com/app/files/docs/refractor_documentation.pdf

[ultimo]

Thank you for the suggestion.

I know that i totally butchered this one, my soldering iron was behaving weird at some point, and by the time i made a lot of the soldering that looks horrible. So the voltages are good at the IC-s in your opinion too? Thats a relief...
here are some pictures, I know it looks awful, hopefully with more practice it will be nicer the more I make these. can you spot anything?
I will also try removing some of the excess solder then reflowing every connection. Will report back with the result too.

[ElectricDruid]

IC1 pin 5 looks wrong to me. I don't expect 0V there. Maybe Aion can explain to me why? I don't want to tell you what your circuit should read, but it seems weird at first glance.

Since that's related to the Gain pot, it might be related to the problem. I'd double-treble-check all the joints in that area.

Pin 3 is a bit odd too, since it's supposed to be biased to the same 4.5V VR supply as the rest. The fact that pin 1 and pin 2 show good voltages suggest this is working, but I'm not sure why it would drift about. Read low, ok, that could be meter loading - but the meter loading shouldn't wander up and down!

[ultimo]

Hello,

thank you, yes I re-checked it measures 4,51V as well at IC1 pin5.
Also the drifting voltage at pin3 IC1 drifts from 3,5 to a lower 2,88V and then it stays there.

I also re-flowed all the joints today, after I plugged in the voltages seem to be the same.

The pedal sounds with the gain to the minimum the loudest, also there is just a hint of drive to the signal Im getting, I guess this would be the normal minimum gain to this pedal (Im using a telecaster with single coil pickups, to a fender bassbreaker 15 combo)

As I turn the gain pot towards maximum the sound gets cleaner (all the drive is gone), and more dull as if it worked as a low pass filter (I lose the high frequencies just like I would if I dialed the pedals tone knob to minumum...)

any more suggestions? Im really hoping this can be fixed somehow and I will learn from it.

Thank you and also I wish all of you a Happy New Year!