I have found a fix for the non-symmetrical PWM pot response on the Model 15. Please open the photo entitled "R39" in the Misc folder in Photos. R39, which is located directly above IC6 as shown, should be changed from 330K (orange orange yellow) to 220K (red red yellow). - P
Message
Model 15 PWM non-symmetry
2006-09-29 by (i think you can figure that out)