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broken big muff, need help

7/7/2000 12:15 AM
john	broken big muff, need help i have just bought a broken Big Muff Pi thinking it would be a great project, but i was wrong. It appears as though somone has tried to rewire it, but was unseccessful, so they decided to sell it. On the board, it says "EH1322". i do not know anything about pot dates, but the tone pot reads "1377833" and the volume "1377840" and the sustain pot was missing(i replaced it with a 100k pot). The on/off switch was missing so i added a Carling SPDT i had. Almost all of the wires look replaced. on the far right of the board(solder side), lug 3 of the volume isn't connected to anything(there is a hole where a part appers to have been). also, right below the hole, is another hole connected to a resistor which is connected to lug 1 of the volume pot. Both of these holes have solder on them. i tried the circuit with the holes linked together and with them not linked, both ways without any sound. I found a schematic for an IC big muff, but the schematic had three IC's and mine has only two. I also tried 9 different wiring schemes without any luck. When i depress the switch once(the effect off), there is sound. when i try to turn it on, there is no sound. I have tried many of aron's debugging methods without any luck. Any suggestions, schematics, or pictures of the big muff's guts would be greatly appreciated. Thank you

7/7/2000 12:15 AM

john

broken big muff, need help

i have just bought a broken Big Muff Pi thinking it would be a great project, but i was wrong. It appears as though somone has tried to rewire it, but was unseccessful, so they decided to sell it. On the board, it says "EH1322". i do not know anything about pot dates, but the tone pot reads "1377833" and the volume "1377840" and the sustain pot was missing(i replaced it with a 100k pot). The on/off switch was missing so i added a Carling SPDT i had. Almost all of the wires look replaced. on the far right of the board(solder side), lug 3 of the volume isn't connected to anything(there is a hole where a part appers to have been). also, right below the hole, is another hole connected to a resistor which is connected to lug 1 of the volume pot. Both of these holes have solder on them. i tried the circuit with the holes linked together and with them not linked, both ways without any sound. I found a schematic for an IC big muff, but the schematic had three IC's and mine has only two. I also tried 9 different wiring schemes without any luck. When i depress the switch once(the effect off), there is sound. when i try to turn it on, there is no sound. I have tried many of aron's debugging methods without any luck. Any suggestions, schematics, or pictures of the big muff's guts would be greatly appreciated. Thank you

Replies:

Pete John,It's a real pa... -- 7/7/2000 12:51 AM
john thanks a lot pete for your help, i ... -- 7/7/2000 1:02 AM
aron John,I am guessing ... -- 7/7/2000 3:26 AM
floydfan John, I know what your talking abou... -- 7/7/2000 4:55 PM