SOLVED Pro-10 green side no gain low output

[Grazza]

Hi all,

Just finished those pro-10, blue side works great, green side however has really low output and no gain really to speak of. There is some sound coming though but not much. When green and blue on together it drops everything down to green output. I'm baffled! I noticed someone else has similar problem but not solved yet either. Any assistance would be greatly appreciated. Pic attached.

 

[BuddytheReow]

Pretty much. It would also be worth your time inspecting all your solder joints and reflowing any cold ones. They will look like balls rather than Hershey Kisses

 

[Grazza]

Will do

 

[GizzWizzKing]

So just follow the schematic (of which there isnt one on this build) and follow the signal till it stops and that is the problem area?

There is a schematic for the individual sides of the pro-10 and that should get you 99% of the way

 

[Grazza]

Cool, are they in the build docs for the circuit boards for the green side?

 

[music6000]

It's been on the forum for 2 years if you look hard enough!
https://docs.pedalpcb.com/project/Schematic-Pro10.png

 

[Grazza]

OK, Reflowed every solder joint to make sure they were good before I used the audio probe. Effect works outside of the box, doesnt work inside the box. Something must be grounding out or shorting right?

 

[music6000]

Do you have plastic dust covers on the Tone pots?

 

[Grazza]

yes, there has to be something going on though, should i probe it while its together, or pull it out again and see what i can see?

 

[music6000]

This has happened to me once & it was a cracked wafer board on one of the Pots, it worked outside but when in the enclosure & the nuts were tighten, the trace must have separated???
Loosen the nuts while in the enclosure & wiggle the pots & see if it cuts in & out.
Take it out & flex the pots & see if it cuts in & out???

 

[Grazza]

I'll have a look, gotta pull it out of the box again anyway, am I supposed to get more than just buzzing when I touch the audio probe to components?

 

[music6000]

I'll have a look, gotta pull it out of the box again anyway, am I supposed to get more than just buzzing when I touch the audio probe to components?

If you do it correctly, you should have sound from a looper or cd player connected.

 

[Grazza]

I dont have a looper unfortunately, its definitely on the list. I have a reasonable feeling its the tone pot of the green channel. The effect cuts in and out a bit more so when it is wiggled than the others. Everytime I put it in the box it doesnt work, but will work evrytime out. Is it possible to remove a pot at this stage without making a massive mess. I Havent even got a spare to replace it with. So frustrating.

 

[Grazza]

I dont know how to explain this, but if the pcb is in the enclosure with nothing tightened up but the foot switches and I push up on the pot shafts pushing them away from the enclosure the effect starts to work, as sson as I let go, it stops working. This happens with every pot, both green side and blue side

 

[Grazza]

Turns out I'm a moron. I have to apologise to everyone for wasting their time, and I really appreciate everyones efforts. I generally use metal LED Bezels on my builds, the chrome ones. No drilling template with this one, but It's all good I'm a builder, I got this! Thought I'd be real efficient about it and drill the LED indicator holes directly below where they come out on the PCB. Nailed it. It was really easy to line up the LEDs, switches and pots when putting it all in. What I didnt think of was that the Tone pot on each side was really close to the LED holes that I drilled. So, when I put it all into the enclosure, the metal bezel I use to hold the indicator LEDs shorted one leg of the tone pot. Why it only did the green side, I don't know. Possible the pot leg the bezel touched on the blue side was goinfg to ground anyway. Anway, replaced the bezels with plastic ones and everything works fine. Nice sounding pedal too. Just one pedal left to trouble shoot.

Once again, I'm an idiot and I'm sorry for wasting everyones time. Can't believe it took me that long to find the problem!

 

[music6000]

The old Led touching the Metal Bezel has caught a few out too!
Glad you persisted, now the Trembling Lune!