Digitek Monitor (Hansol E17BL) "enlarge" then "shrink" problem

[Richard]

Hi!

I have a problem with my monitor, where the display of the monitor "enlarge"
then "jumps" back to a smaller size (shrink) repeatedly. The difference is
about 3 to 5mm all sides (top, bottom left right). However the center of the
display remains unchange. I think when the problem begins this effect was at
a slow rate then now it is happening at a rate of about once to twice a
second.


I guess it is the problem of some of the DC supply has a faulty cap.
Unfortunally I am unable to get hold a schematic.
Does anyone have similar experience. Do you think I should continue to
measure the caps using the scope or could the problem might something else,
such as faulty fly back?


Thank You

Richard

 

[Jerry G.]

The main power supply, or high voltage supply is not regulating
properly. This can be due to anything from a cold solder connection, to
failing component(s).

You would have to get in there with a DVM, and start taking readings to
see where the failure is. You will most likely need the service manual,
if you are not familiar with the monitor.

I would strongly suggest that if you are not used to working in
monitors, and properly trained to do so, that you should be aware of
the extreme safety issues when going in to a monitor.

Jerry G.
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