SOLVED Special k more pot not working

[scabiosa]

Hi folks

I just made the special k. Everything works, except the More pot only works when it is at the maximum. If I measure with the multimeter from lug 1 to R4, I measure 390 ohms. If I measure from lug 2 to R4, I measure 390 ohms, but only with the pot at max. When not at the maximum, I measure no value at all. Could this be a faulty pot or is there more that i can check?

 

[JohnnyCreepy]

This might be related to your issue. I’d say you really need practice how to make your solder really flow. Most of the component connections on the PCB look like cold solder joints, but it’s fun to notice MORE pot has best joints.

 

[Robert]

Which meter are you using?

It sounds like this might be normal behavior on a meter that is measuring out of it's range.

 

[scabiosa]

Yes indeed, multimeter was in the wrong position. when i put the multimeter on 200k ohm i read different resistance values between R4 and the ‘more’ pot lug 2. So not a faulty pot…

Will also redo some solder joints. I guess there is a chance that helps…
Thanks!

Which meter are you using?

It sounds like this might be normal behavior on a meter that is measuring out of it's range.

 

[Locrian99]

Yes indeed, multimeter was in the wrong position. when i put the multimeter on 200k ohm i read different resistance values between R4 and the ‘more’ pot lug 2. So not a faulty pot…

Will also redo some solder joints. I guess there is a chance that helps…
Thanks!

Your components look fine to me solder joint wise you have solder flowing through the pads. Your switches both I like to try to fill the pad but be cautious as you can end up with a solder bridge underneath that you don’t see. When you say it doesn’t do anything til the end? Do you mean you’re not noticing much of a difference then theres a big difference towards the end? It could be a taper issue. Im not familiar with this particular pedal, but similar set up often use a c taper for this exact reason.

 

[scabiosa]

Damn, problem found!
i fucked it up and installed the b10k at the place of the a100k…

I have these desoldering tools but somehow i can’t make it work properly. Normally i just heat it and try to pull the wrong stuff out, but this time its not working too. Solder at both sides of the pcb…

Is this the right kind of wick? or do i need to add some flux before wicking or sucking? Anyway, searched in the forums and youtube but still struggling with desoldering . Any tips?

 

[z2amiller]

Damn, problem found!
i fucked it up and installed the b10k at the place of the a100k…

I have these desoldering tools but somehow i can’t make it work properly. Normally i just heat it and try to pull the wrong stuff out, but this time its not working too. Solder at both sides of the pcb…

Is this the right kind of wick? or do i need to add some flux before wicking or sucking? Anyway, searched in the forums and youtube but still struggling with desoldering . Any tips?

Do you have some spare pots? How sad would you be to lose that A100K?

Truth be told, if you don't have good desoldering tools you're way better off using
wire cutters to snip that pot off of the board, and then desolder each of the pins
individually. That's way easier than trying to desolder a big honkin 3 pin component.
By cutting and then desoldering each pin in order, you can just pull the pin out with
pliers/tweezers while the joint is hot, and then clean up the hole with the desoldering wick.
Use a ton of flux if you have it, makes the cleanup go better.

The only thing I've found to reliably get pots off of the board is a big chisel/shovel
tip that can heat up all three pins at the same time. You can approximate
this by using a thick copper wire across all three pins but honestly it's probably
not worth it to save a $0.39 pot.

 

[scabiosa]

you're way better off using
wire cutters to snip that pot off of the board, and then desolder each of the pins
individually.

exactly what i did. Did not gave up the pots bt snapped them and rewired them in the correct place. Pedal works perfectly now and really like what its doing!

But really would like to hear what is considered to be the best desoldering method:
- heat it and wriggle?
- also saw some people use desolder needles with variable thickness?
- for me desolder pump or wick never got good results up to now… but you are saying with a wick tons of flux might help, ill try that next time! Thanks!