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Paul
 
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Default Viewsonic PS790 G2 Voltage Measurement

I have a Viewsonic PS790 monitor with no raster. HV is a solid 25KV, and
the CRT filament lights up. G2 screen voltage is supposed to be 600v, but I
measure about 130v at start up, and within a few seconds it's down to about
75v... same results with socket removed from CRT. I assumed that the HV
divider resistors in the flyback are bad, but someone suggested that the 10
Meg input impedance on my DMM is too low for measuring the screen voltage,
and may be loading it down. Is that true?

(The schematic shows the focus and screen divider resistor chain, but does
not list values for any of the resistors or pots)

TIA,
Paul