fatman lfo

[Wendy Bardsley]

Hi,  
This is my first post to this list. I'm looking for an lfo for my fatman. 
I've seen all the fatman mods on the net, but I need one that produces saw
/ reverse saw. Ric Miller has one that is very simple but it calls for + /
- 15v, can someone tell me if this can be modified to work with the fatman
power supply? or can anyone tell me where I can find a schematic for one
that will work with a -12v, +8v, +5v power supply?  I hope I'm not asking
stupid questions, but I'm just a guitar player with a soldering iron, I
don't know how any of this stuff works, I just know how to follow a
schematic and put it together. 
 
Dave.