10-18-2022, 11:22 AM
Hi Glenn,
I've been looking at the fine refinement voltage chart. It appears some of the tube bias voltages are wrong. If you look at the grid of XXL tube one it connects to the bias network in the power supply. You show 47 volts and it should probably be -5. My first question is when you replaced the power supply filter cap 83, did you connect the negative lead to ground? If not then we should measure the voltage between ground and each junction of the voltage divider resistors 82, 82A and 82B. You should get 3 negative voltages.
I've been looking at the fine refinement voltage chart. It appears some of the tube bias voltages are wrong. If you look at the grid of XXL tube one it connects to the bias network in the power supply. You show 47 volts and it should probably be -5. My first question is when you replaced the power supply filter cap 83, did you connect the negative lead to ground? If not then we should measure the voltage between ground and each junction of the voltage divider resistors 82, 82A and 82B. You should get 3 negative voltages.
![[-]](https://philcoradio.com/phorum/images/bootbb/collapse.png "[-]")
