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Hey everyone. I just built the Runoffgroove Twenty-two Sevenths, which is a CMOS-based Big Muff. However, when I fired it up, the volume is incredibly low, well below unity even with all pots turned all the way up.
Did a bit of troubleshooting and I think I have a promising lead on the issue but I'm not sure where to go next. When I plug the pedal in and probe pin 1 of the CMOS (which is VDD), I only see about 5.4V, even though my supply is providing 9v. There's a 470R resistor between the 9v in and that pin 1, and it has a 3.6v drop across it, which seems way, way too high.
I can't figure out why that supply voltage would be getting yanked down so far, but it seems reasonable that if I can get it back up to ~9v, maybe my volume will come back. Any ideas? A multimeter doesn't show any path from pin 1 of the CMOS to ground (other than through a 100U cap) so I don't think its accidentally creating a divider.
Any help would be hugely appreciated!
Did a bit of troubleshooting and I think I have a promising lead on the issue but I'm not sure where to go next. When I plug the pedal in and probe pin 1 of the CMOS (which is VDD), I only see about 5.4V, even though my supply is providing 9v. There's a 470R resistor between the 9v in and that pin 1, and it has a 3.6v drop across it, which seems way, way too high.
I can't figure out why that supply voltage would be getting yanked down so far, but it seems reasonable that if I can get it back up to ~9v, maybe my volume will come back. Any ideas? A multimeter doesn't show any path from pin 1 of the CMOS to ground (other than through a 100U cap) so I don't think its accidentally creating a divider.
Any help would be hugely appreciated!
