[sdiy] students in aaron's class need help

[René Schmitz]

Hi Christine and all,

> Hi, I'm in Aaron's class and my partner and i are working with this schematic
> http://www.lynx.bc.ca/~jc/phase45modded.gif
> we breadboarded it and are having some difficulty with it
>  we can't seem to get any ac signal past the first amp

I presume you have tried using another opamp to make sure its working.
I can't see anything wrong with the circuit per se, so maybe the problem 
is in the wireing. The DC levels at both + and - as well as the output 
should be 5.1V or thereabouts, with no input signal present (golden 
opamp rules). Also make sure the voltage at the zehner is really 5.1V or 
near that. I'd suggest measureing these and see if that takes you 
somewhere.

> the author mentions on his page at the bottom: http://www.lynx.bc.ca/~jc/pedalsPhase45.html
> he explains matching the fets. would that be one of the main issues we need to deal with in order for this to work properly?

For that to matter you first need to get the signal out of the first stage.

Cheers,
  René

-- 
uzs159 at uni-bonn.de
http://www.uni-bonn.de/~uzs159