madbeanpedals::forum

Projects => Tech Help - Projects Page => Topic started by: Gristlepig on June 01, 2018, 09:39:57 AM

Title: Mangler Volume Pot Issues
Post by: Gristlepig on June 01, 2018, 09:39:57 AM
Howdy gang,

I just recently built up a GE Fuzz Face using the Mangler 2011 pcb. It sounds great, but it is LOUD. The volume knob doesn't seem to dump out entirely to ground, as at fully CCW, it is louder than unity. It just gets much louder from there. I pulled the 500k volume pot and replaced it with a 100k, and while I like the brighter tone better, much like the 500k, the pot seems to do very littleā€”it just goes from loud to a bit louder at the last 20% of the pot's rotation. My voltages are right where they should be, and all of my component values seem to be correct.
Has anyone else expereinced this with the Mangler 2011 board?
I've built many a Fuzz Face in the past, both GE and SI without problems (the vol goes silent at full CCW) but this one has got me stumped.

Transistors are old TI 2G308 at 60 and 120 hfe, very minimal leakage.

Title: Re: Mangler Volume Pot Issues
Post by: madbean on June 01, 2018, 09:42:31 AM
Check for continuity b/w lug1 of the Volume pot and ground first. Show a pic and or voltages as well.
Title: Re: Mangler Volume Pot Issues
Post by: Gristlepig on June 01, 2018, 09:43:58 AM
Will do. Heading back down to the solder dungeon shortly.
Title: Re: Mangler Volume Pot Issues
Post by: Gristlepig on June 01, 2018, 10:07:43 AM
Aha! No continuity between lug 1 and ground!
Title: Re: Mangler Volume Pot Issues
Post by: Gristlepig on June 01, 2018, 10:10:27 AM
That's odd. Lug 1 appears to be connected to the ground plane on the pcb. Perhaps I burnt up the connection when soldering the pot in? I dunno, I don't usually apply too much heat when soldering.
Title: Re: Mangler Volume Pot Issues
Post by: Gristlepig on June 01, 2018, 10:17:45 AM
Running a jumper from lug 1 to ground solved the problem.
But now it sounds way too bright. Time to throw the 500k back in.

Thanks for the heads up Brian.