- This topic has 3 replies, 2 voices, and was last updated 14 years, 8 months ago by .
Viewing 4 posts - 1 through 4 (of 4 total)
Viewing 4 posts - 1 through 4 (of 4 total)
- You must be logged in to reply to this topic.
Home › Forums › Help/Technical Questions › Ram’s Head — Sustain pot is a volume pot?
What could turn the Sustain pot in an old ram’s head muff into a second volume pot? Bad caps? Bad pot? Something else?
I picked up a later 70s BC239C ram’s head muff cheapish with a broken switch. Installed a 3PDT wired for TB and it worked but didn’t sound right and turning down the Sustain also drops the volume. None of my other ram’s heads do this, so I figure something is amiss. also, at maximum sustain it’s not really singing like a muff. Something’s not … engaged?
So I opened up and repaired the old switch just in case it was my TB wiring, rewired it as it was originally, and the same thing. I figure some other component(s) is knackered. Any idea where to start looking. What could lead to the Sustain pot turning down the volume?
Tone pot seems a bit off as well actually — with treble at both ends of travel and a bit muffled in the middle.
EDIT: Just pulled the board and C1 looks to be newer than the others. It’s 10uF electrolytic marked SURGE
Mine’s the same as this one. Which side should be negative on the C1 cap in this pic? Left or Right?
Replace all the electrolytic caps and see if that helps. When they leak voltage it’ll throw the other stages off.
Thanks Ron — quick check on orientation. In this pic, C1, C2 and C7 have -ve to the left,C6 has -ve to the right?
C1 is 10uF, while C2, C7, and C6 are all 1uF…
It’s hard to tell as it seems some of them are twisted around. Just mark the board before you remove them so you can be sure to put the new ones in correctly. I’d replace the 10uf first. That’s the style I’ve seen go bad more often.