Pulse generator and tuning Gecko 320 drivers....

I've been trying to get my Gecko drivers tuned. I tried Dan Mauch'
scopeless method and it isn't working for me. I would like to use a
pulse generator and a scope. I'm trying to find a schematic for a
pulse generator that has adjustable step frequency and reversable
direction output. At least that's what I think I need.

I've looked at all the circuits in the files section and can't find
one that really looks like what I can build from Radio Shack parts
and a breadboard.

The one Mariss put up in the Circuits directory 'Manual Pulse
Generator.pdf' looks to have the clearest explaination of the hookups
to me. I.e. it tells me what to hook up to STEP and DIR.

What I'd need to know is how to adjust the frequency. Is R2 a pot? C2
changes the frequency range. What values for C2 do I use to try other
ranges?

R3 and C3 differentiates teh pulses so they are 10 uS wide. Is that
long enough for what I'm doing? If I need to change these, what would
I change them to?

What is the 4093? I assume there are 4 of them needed, whatever they
are.

Would a wall wart work for the power supply? Does this circuit have
the fortitude to handle that type of power supply?

Thanks for your help. I'd really like to get the drivers tuned
correctly so I'm not overworking or overloading circuits, motors, etc.

Regards,
Monte