audio probe sweet 16

[mhartington]

so after building the Doug Hammond Sweet16, i fail in some way getting the circuit to work. Every thing is wired up correctly and i cant quite figure out whats wrong. Its got a charge pump in the circuit to get 17volts. I tried to audio probe it and i couldn't even get a signal from the input jack. Im a beginner at build pedals from scratch so any help i could get would be fantastic. HELP!

layout with parts
www.geofex.com/PCB_layouts/Layouts/sthart.pdf

I cant find the schematic so i cant provide that

[mhartington]

hey found the schematic,

http://www.aronnelson.com/gallery/main.php/v/WGTP/Sweet16.gif.html?g2_imageViewsIndex=1

[DougH]

I never could get it to work with a charge pump, I don't know why. I just used 2 batteries and called it a day. Now that circuit is in my "circuit graveyard" drawer and the box was reused for something else. That was a long time ago...

[mhartington]

now this is way beyond my understanding but i got the pedal to work, but only when the positive tip of the power jack touched the enclosure? I dont understand it but how can i fix this

[GibsonGM]

It sounds like you have a problem with your power supply.  Maybe you have the "-" and "+" backwards?  Check the polarity!  Then measure the voltage at the top of each J201 (at the drain), and at each point marked "1/2 V".

For more help, see the thread called "Debugging" at the top of the stompbox forum...do what it says, and then we can help you!   )

[mhartington]

i checked the power jack and its wired right. Very strange, I cant even contemplate how this would happen.  I have a charge pump in the circuit putting out 16.8 votls and as for the voltages from the transistors, it is a little bit difficult to get right now with this power problem. But when i have the power jack's tabs make contact with the enclosure i get an amazing distortion sound so i know the pedal is wired up right and that all the transistors are functioning properly.

[GibsonGM]

Me - I'd take the jack out completely and be sure the pedal worked the way I want.
Then I'd go thru the process of re-installing it, so as to be sure that the jack IS the real problem.  
If touching the eclosure is fixing it, and the enclosure is grounded, then it's like 99.8% probable that there is a grounding issue with the gnd side of the jack, or charge pump circuit, something in the power supply...

[WGTP]

I'm not sure Doug is happy with me continuing to bring this pedal up, but I think it's a great pedal and a heavier option to the BSIAB I & II.  I just use 2 9v batteries and it cooks even with 14v.