Hello again.
I checked the LEDs and discovered that they are both flashing but I hadn’t properly covered them with the heat shrink. I fixed that, re-checked all of the solder points but still didn’t have any effects. I went through the appendix A. As I said, LEDs work and are properly covered. Both trim pots work. In calibration mode, there is no effect from turning the harmonic mix knob. Jumpers are soldered correctly. TP 1 – 4 all read 5.4V. The only variance I can find is the voltage at pin 4 of U2 is 2.2V instead of 4.5. All of the other pins are at the expected voltages.
Any other suggestions?
Alex