WITS END!! maestro FSH-1 voltage bizarreness...

Started by vacuumdust, June 25, 2007, 07:01:19 AM

Previous topic - Next topic

vacuumdust

Built my second FSH-1 using the GGG layout and just like the last one it worked perfectly.  But like the last one, I was swapping differrent transistors in the noise position (Q4) and added an LED after the initial test run to see that the pedal worked.  When I fired it back up the signal is almost inaudible (bypass is fine).  BUT!!! when I pull the DC jack out while a chord is sustaining the signal comes in stronger and stronger as the voltage ramps down to nothing...and I can hear the effect working as it should.    I hooked up a voltmeter and i'm getting +9.7vdc and -9.5vdc from my charge pump just as I should be...but the way the signal comes in as the voltages drop...it's like the pedal wants to run on 3-5 volts, not 9.  Again the pedal worked perfectly before I tinkered with the transistor and LED...I'm guessing I shorted something or blew something but everything seems to test out.  Anyone recognize these symptoms??  I just don't know where else to look.
I even connected 2 weak batteries (about 7 volts a piece) in the bipolar fashion and used those to power it and it's slightly stronger but still exibits the same thing when I pull the power and the volts get down to the 5v to 3v range.
THANKS!!!

GhengisJung

Quote from: vacuumdust on June 25, 2007, 07:01:19 AM
Built my second FSH-1 using the GGG layout and just like the last one it worked perfectly.  But like the last one, I was swapping differrent transistors in the noise position (Q4) and added an LED after the initial test run to see that the pedal worked.  When I fired it back up the signal is almost inaudible (bypass is fine).  BUT!!! when I pull the DC jack out while a chord is sustaining the signal comes in stronger and stronger as the voltage ramps down to nothing...and I can hear the effect working as it should.    I hooked up a voltmeter and i'm getting +9.7vdc and -9.5vdc from my charge pump just as I should be...but the way the signal comes in as the voltages drop...it's like the pedal wants to run on 3-5 volts, not 9.  Again the pedal worked perfectly before I tinkered with the transistor and LED...I'm guessing I shorted something or blew something but everything seems to test out.  Anyone recognize these symptoms??  I just don't know where else to look.
I even connected 2 weak batteries (about 7 volts a piece) in the bipolar fashion and used those to power it and it's slightly stronger but still exibits the same thing when I pull the power and the volts get down to the 5v to 3v range.
THANKS!!!

Did you ever get this figured out? I have finished a FSH-1 and I'm getting nothing more than a significant drop in volume, and no effect. Bypass is fine. I'm powering with 2 9v at the moment.

Thanks!