SOLVED Drive pot problem on bellum fuzz mk1 build

[jarunsky]

Hi,

The drive knob sounds like loud scratchy pot when I turn it. I've tried cleaning the pot with deoxit. Also replaced the pot twice. I've used the alpha branded ones and now the tayda one.

The problem persists. I checked all soldered points and they look fine to me.

I'm out of ideas. I would appreciate any help. Thank you.

 

[fig]

Those don't appear to be 680n caps. Is the 100n a suitable replacement?

 

[giovanni]

Hard to say but I suggest cleaning the board a bit (scrub it with alcohol) and see if that helps.

 

[jarunsky]

The goop's built up after soldering and desoldering that damn pot 3 times. I will clean up and report back.

I sub all those caps with 100n as suggested in manifesto's build report.

I might try replacing the pot with A100 one,

I think I neglected to mention that It works and sounds fantastic except for this one annoying problem. It might replace the EQD cloven hoof on my board as my main dirt pedal.

I also found pinoynoiseboy reporting similar "static issue" with the gain pot. There might be something big going on over her than just a bad pot.

 

[Barry]

That scratch is normal in some circuits

 

[jarunsky]

I found that the 100u cap I had used was rated 10v only, I swapped it out with a 50v rated one, This has tamed the noisy pot problem and now the pedal is quite usable. Thank you for your replies.

Here's a picture of it sitting smugly on my board

 

[Feral Feline]

Mark it SOLVED!

 

[jarunsky]

Done Thanks!

 

[fig]

Excellent read! Anyone starting out, remember to use components rated for at least 1.5x the operating voltage.......yes I did learn the hard way.