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Russian Black Big Muff Problem

7/23/2004 10:16 AM
Richard Blackman
Russian Black Big Muff Problem
I've got out my big muff the other day to find that the output had decreased to a point where you can hardly hear it (and is pretty much silent when it's off) sometimes when playing the output increases and decreases every 10 seconds or so.  
I'm a bit of a newbie when it comes to fixing effects but I like to get my hands dirty, has anybody come across a similar problem to this, or could you tell where to start in fixing this effect? I can solder and I have a multimeter to test with.  
Richard Blackman
7/23/2004 8:44 PM
Mark Hammer

Cyclical increases and decreases in output level can sometimes be an indication of battery "gasps". I often get this with little transistor radios, although the frequency is usally a little faster than once every 10 seconds.  
The two things to verify here are that your battery is as alive as you believe it to be, and the contacts on the volume pot are as clean as you believe them to be.
7/26/2004 9:03 AM
Richard Blackman

Sorry I think I mustn't have explained that bit properly, there isn't really a cyclical increase or decrease in volume it just happens every so often randomly.. sometimes it's quiet sometimes it's louder (but it's always not loud enough). It's sort of like a faulty connection but I can't really be sure. I've tried replacing the volume pot and have checked the battery I also resoldered some of the dodgier looking joints.. still no joy :-(  
It's too quiet even when it is off.  
I was thinking could this be something to do with the amplification stage of the unit? I could probably get my Dad to show me how to test the transistors..  
Thanks for the help =D  
8/8/2004 6:09 PM

hello, i'm experiencing the same problem. i thought it might be fixed if i replaced the stompswitch, but i havent yet. i don't know much about electronics. has anyone overcome this problem yet?  
8/9/2004 5:19 PM
Alvaro Salinas

I had 2 russian ones for doing some mods and one had the same problem that you've explained. I bought a nwe 100k linear pot for the volume control and replaced the cheap one that comes with the russian ones. I had to modify the shaft to accept the knob that comes with the unit.  
I have some problems witha 3PDT switch from Sovtek.. maybe that could be a part of the problem but my instinct says that it's the volume pot, maybe some dirty tracks on the internal construction or some poor soldering job in the plastic jacks  
good luck
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