SansAmp Classic... anyone else built one?

[Gila_Crisis]

looking at the pics i've done of the perfboard, i realized why the dip switch nr.7 works wrong, but it's only a little mistake made by myself, nothing to worry about.
otherwise you can take my project as VERIFIED, and build your own Sansamp Classic without any problem!!!

[bluesdevil]

Great job on this project, Gila!! I'll will add it to my build list.

[caspercody]

I made the Sansamp Classic using Gila_Crisis pcb layout and am having trouble. I get no noise out of it, works in bypass. So I started using a audio scope, and get noise into the gate of Q1, but nothing out of the source. I took the common wires off of the 3 way switch and just tried to see if I get anything out of the buffered out, nothing. So I connected the input onto R15, bypassing the input buffer, and I get noise. It is a shorted sound. I hooked up the audio scope again, and get clean sound into pin 3 of IC1a, but shorted noise out of pin 3. I have checked the pcb with a DMM, and have found no shorts. Not sure what to try next???

[caspercody]

Just read a little article from RG on if pedal does not work. And when I measure everything, here are the voltages:

Q1
Drain 7.93v
Gate 4.183v
Source 0v

IC1
pin 1 4.381v
Pin 2 4.58v
Pin 3 3.67v
Pin 4 0v
pin 5 4.34v
Pin 6 4.38v
Pin 7 4.41v
Pin 8 7.93v

IC2
Pin 1 4.386v
Pin 2 4.386v
Pin 3 4.357v
Pin 4 7.91v
Pin 5 4.373v
Pin 6 4.383v
Pin 7 4.382v
Pin 8 4.36v
Pin 9 4.24v
Pin 10 4.25v
Pin 11 0v
Pin 12 4.354v
Pin 13 4.383v
Pin 14 4.359v

All are close, maybe input 1 on IC1 is off?

And reading his description, I have to hit the strings hard to get any output (and again this is bypassing the input buffer, get no sound with buffer connected) and the sound is shorted sounding or gated.

[caspercody]

I have been working on this to get it to work. And gone as far as removing all switches, and most of the input buffer. When this was all together, I had the controls cranked and barely got any noise. If I hit the strings hard I got the noise but sounded shorted, gated sounding. When I turned the volume control I get a crackle sound (crackle not okay). Now with switches removed, and input buffer still the same problems.
I am still getting almost 1 volt lower on my first stage of IC1 (see previous post). Does anyone have any voltage readings? Should these pins all be close to the same voltage? What what effect the voltage for that first stage?

Thanks
Rob

[askwho69]

GILA HI! any soundclips? how does it sound? compare to SansAmp gt2?
Thanks!

A2

[antisyst]

Hey guys........
i know this thread is a little old but...
took the liberty of painstakingly Labeling The schem as seen in bill's pics (according to pcb and layout) thought this might help... i couldn't find a parts list for the layout anywhere..... until i get around to posting it somewhere, if you want a copy email me @ fecalma100@aol.com and i'll send it to ya....   

[steab]

Hi !

Mine doesn't work too...

[steab]

Now it's working..

Bad IC placement