KV9200 Issues

[vol.2]

Originally Posted by Alex KL-1

If focus adjustment are great at near top, you can add a some Mohms resistor from "cold" wiper from potentiometer to ground (in series with potentiometer), reducing the loading, and making the focus adjusment less coarse.

The actual voltage at the 530V boost line measures at about 560VDC at the source. The focus looks best at something like 400VDC.

[Alex KL-1]

Good, so is possible to add the resistor.
BTW: I wrote "in the wiper" (perhaps making some confusion), so I can explain better: the resistor needs to be added in series with the ground side of it; the pot. pin dedicated to low voltage, and potentiometer being only a part of the divider. Like a 3M3 resistor in the ground side, then to the one leg of pot. The movable part of it goes to focus grid, and remaining part of the potentiometer simply goes to 530V. Total, more than 4M, better than the only 1M from potmeter.