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viewsonic monitor screen size fluctuation

i bought a viewsonic CRT with the model number E90f + SB. it had a strange problem where, the size of the screen fluctuates according to the image being show. For example, if i set the viewing area to almost the full size of the screen and open a window ( say Windows explorer ), the viewing area automatically increases and, i cant even see the File menu because it is out of the viewing area. I checked about 6 monitors of the same model from the supplier, but all of them had that problem. Since there are no other good brands for 19 inch monitors available in my area, im in deep trouble.

Can this behavior be normal for a monitor? if this is a problem in the monitor, can this be repaired ?

thank you. CMOS.

Reply to
CMOS
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Reply to
Mike Berger

A very small amount of fluctuation is normal on inexpensive monitors, that definitly sounds like a problem though, I had a Viewsonic monitor for years that didn't do that.

Reply to
James Sweet

I really doubt that. An image that grows with more white on the screen sounds like bad HV regulation to me. Deflection sensitivity is an inverse function of accelerating potential; high brightness => more beam current => drop in accelerating voltage => electrons spend more time in the influence of the deflection coils => image gets bigger; q.e.d.

Isaac

Reply to
Isaac Wingfield

thank you for all replies.

The VGA cards i used are different. im sure its not a problem in the video card. The fluctuation is not small. it about one inch !.

can that problem be repaired ?

thank you. CMOS

Reply to
CMOS

Any problem can be repaired, from the sound of it it's a problem with the high voltage regulation, though I'm puzzled by what you said about it being the same on several new monitors.

Reply to
James Sweet

Definitely sounds like poor regulation. Usually a small fraction of an inch can be noticed on some low end monitors, but an inch is completely unacceptable for a monitor indicative of either a dismal design or a fault.

If it's a known design fault on that model, probably not without a service kit, if one is even available. An inch really is very bad though, it sounds like a serious problem. I'd take it back and insist on a replacement.

Dave

Reply to
Dave D

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