I was just working on the PI trimmer, this trimmer appears to slightly adjust the voltage to the plates of the PI. I found my plate voltages were not exact to the schematic, I have 300V instead of 280 on pin 6 and 285 instead of 290 on pin 1. Adjusting the trimmer in my case resulted in minute changes, couple volts. If I wanted to get the voltage closer I would be looking at changing the values of the resistors between the trimmer and plates. I put a signal on the input to the PI and scoped the output of the amp. Nothing lop sided, nothing irregular, looks good. I'll be working on the OD section next, let you know what I find
I was just working on the PI trimmer, this trimmer appears to slightly adjust the voltage to the plates of the PI. I found my plate voltages were not exact to the schematic, I have 300V instead of 280 on pin 6 and 285 instead of 290 on pin 1. Adjusting the trimmer in my case resulted in minute changes, couple volts. If I wanted to get the voltage closer I would be looking at changing the values of the resistors between the trimmer and plates. I put a signal on the input to the PI and scoped the output of the amp. Nothing lop sided, nothing irregular, looks good. I'll be working on the OD section next, let you know what I find