plz HELP with faulty MuTron III!

Pacafeliz · Post by **Pacafeliz** » Mon Jan 05, 2009 12:50 am

hey guys... looking thru the all my broken and fixer-upper projects stuff i came across an old Musitronics Mu-Tron III pedal. it has the original PS-1 power supply attached (hard wired) to it and the battery cables removed.

it kinda works.
yeah...

so before i offer it for sale for peanuts, i want to try some things to see if i can bring it back to work as it should.

the power supply "pilot light" dimmers and flickers a bit, so it's not solidly ON, so to speak. so i suppose there could be the prob. i'd need to read how much voltage gets into the pedal.

then, the pedal itself:
when turned ON (the red plastic switch), the GAIN pot controles the volume of the guitar, even when effect is turned off (stomp switch)!!! and when on full it makes the guitar distort, even when off! wtf?!

then, when i turn the effect stomp switch on, the DRIVE (rocker switch) set to "down", it kinda works. it does the envelope effect and all, but it cuts it out pretty fast, not gradually as it should. but it does the MIAAAWWW thing.
but when set rocker switch is set to "up", the effect does not work. i mean, it "closes" the sound but it doesn't "open it up" (wah) as it's supposed to.

the HIGH/LOW rocker switch, as well as the MODE 3-way pot work ok as they should. they cut out or lift the frequency as they should.

now...
the circuit looks all a-ok and no obvious mods (other than the power supply thing). it's old but there are no evidence of broken, burnt out or changed components.

...any ideas? i'll try anything.

thanks,

Pat.

stewart · Post by **stewart** » Mon Jan 05, 2009 1:40 pm

that sounds like what my one does. they're bloody weird pedals, took me ages to figure out how to get it to do anything other than cut treble frequencies. i don't think there's actually anything wrong with yours, they're just temperamental as hell. could be mistaken though.

that's not much help, is it?

Pacafeliz · Post by **Pacafeliz** » Mon Jan 05, 2009 3:21 pm

thanks man!
no but i've had several of these and they are fn' crazy insane and great sounding boxes!!! auto wah/enveolope filter (wuaaaa or miaaaaauuwww), but this one doesn't do it right....

thnx, and get yours fixed too!!!

Pat.