madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: dfine22 on September 19, 2011, 12:49:15 PM

Title: Chunk Chunk Gain and Volume pots do not work
Post by: dfine22 on September 19, 2011, 12:49:15 PM
Hello, just build a chunk chunk. Presence and  BMT work fine however volume and gain pots do not do anything.  Trannies are biased fine. Cant figure it out. Any help would be great. Thanks
Title: Re: Chunk Chunk Gain and Volume pots do not work
Post by: mgwhit on September 19, 2011, 01:18:32 PM
Given that the Gain and Volume pots are in-line to the signal path, they have to affect you signal in some manner.  What kind of output are you actually getting?  Do you feel like you are getting maximum Gain and Volume at all settings?  If so, they're probably just not connecting to ground properly.  Check for continuity between lug 1 and ground on both pots.  Might just be bad solder joints.

As usual, pictures help....
Title: Re: Chunk Chunk Gain and Volume pots do not work
Post by: dfine22 on September 19, 2011, 01:37:42 PM
It is probably middle output in terms of gain and volume.  I turn either pot either way and no influence at all. Just not sure which way to go re; trouble shooting. Its strange.  ???  At work so noavailable images except at BYOC where I posted it in forum "Show off Your Pedal".
Title: Re: Chunk Chunk Gain and Volume pots do not work
Post by: jkokura on September 19, 2011, 02:32:55 PM
Have you read our "rules for getting tech help" thread? That would be a good start for helping you learn how to trouble shoot.

Most problems with pedals come down to either a part that's the wrong value, orientation, or to poor soldering or wiring. I suggest you take some time and carefully go through your pedal and double check your parts. Don't assume they are correct. Also, closely examine your soldering and your wiring. Triple check it all. If it's still not working, post some of your results from testing and some pictures and perhaps we'll be able to help you get the pedal going.

Jacob
Title: Re: Chunk Chunk Gain and Volume pots do not work
Post by: mgwhit on September 19, 2011, 02:48:02 PM
I checked out the pics at BYOC, and it's a nice looking build.  I couldn't see the solder joints from the pots to the boards too well, but they looked like they might be a bit splotchy.  Close ups of those would be nice, as those might need to be touched up.

The other thing I noticed is that you used the same color wire for all of the board-to-pot connections.  Nothing wrong with that -- I frequently do the same thing -- but I'd check to see that you didn't mix up a couple of the wires.

Medium output was not what I expected. If the Gain and Volume pots weren't properly grounded, I would expect the pedal to be full on, so you might have some problems elsewhere in the circuit, too.  You definitely want to follow Jacob's advice and read through the "tech help" thread.  A signal probe is really a requirement for all but the simplest fixes.  Good luck!
Title: Re: Chunk Chunk Gain and Volume pots do not work
Post by: dfine22 on September 28, 2011, 09:58:32 AM
OK got it up and running.  A bad gain pot.  Thanks especially to Matthew for your help!
Title: Re: Chunk Chunk Gain and Volume pots do not work
Post by: mgwhit on September 28, 2011, 12:28:55 PM
Congratulations -- have fun with it!