I got this power supply from eBay advertised as power up condition only and currently tried to restore it. Replaced some overheat resistors, rectifiers and power supply capacitor and neon bulb. Checked most of the components and tubes and replace some weak tubes. In general most of the components are still within the tolerance. Some exceeded slightly but I don't think it will cause much of the problem and did not replace them.
Attached is the output data after power it up. The main issue is it did not reach the max voltage except as noted in my file. Checked all resistors in the sampling network. They are fine. Negative 250V Bias is fine. I also checked out all parameters per Figure 4-2- Tube Voltage Chart on page 4-3 of the Maintenance section. The voltages are not really matched what specified there and don't know and not sure if they are really related to the issue that I have. One thing that's quite different from what specified in the chart is the pin 9 of V14 (6AU8). The chart said -61V on pin 9. It's measured about -61 voltage when Output Switch Position (0-500V) is in the "0" position only and I don't believe it's correct in other positions. My measurement on pin 9 started to turn to positive voltage when Output Switch Position (0-500V) dialed to position 100 to 500. On "500" position it measured about positive 289V. May be it's typo perhaps.
Appreciated any input on this. Thank you.
Attached is the output data after power it up. The main issue is it did not reach the max voltage except as noted in my file. Checked all resistors in the sampling network. They are fine. Negative 250V Bias is fine. I also checked out all parameters per Figure 4-2- Tube Voltage Chart on page 4-3 of the Maintenance section. The voltages are not really matched what specified there and don't know and not sure if they are really related to the issue that I have. One thing that's quite different from what specified in the chart is the pin 9 of V14 (6AU8). The chart said -61V on pin 9. It's measured about -61 voltage when Output Switch Position (0-500V) is in the "0" position only and I don't believe it's correct in other positions. My measurement on pin 9 started to turn to positive voltage when Output Switch Position (0-500V) dialed to position 100 to 500. On "500" position it measured about positive 289V. May be it's typo perhaps.
Appreciated any input on this. Thank you.
