Build Your Own Arcade Controls Forum
Main => Monitor/Video Forum => Topic started by: ken_cinder on April 07, 2009, 10:11:56 pm
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Having a problem with one of my Nanao MS9-29A monitors, the picture will shrink and expand slightly when what is on screen changes.
Example: Dark title screen showing, fades to black and then a significantly brighter gameplay screen comes on and the screen shrinks and expands back to normal.
It's not staying like that any longer than a second or two, but it's still annoying and I want to stop it.
I tried adjusting B+ and that's not fixing it, adjusting screen level doesn't seem to help either.
What sort of things commonly cause this?
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may be a problem with vreg . i.e. failing to maintain regulation with varying load conditions.
a weak crt can have a similar symptom ( blooming )
qrz
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I was thinking it could be voltage related. It's a 100v monitor, running on 115v. I was told "It's fine, don't worry about it!" but I'm starting to wonder and have been thinking of getting a transformer to throw in there.
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a functioning vreg shouldn't have much difficulty with that .
the line voltage from a household outlet WILL vary some , and that varience will be passed by the isolation xformer.
there are a couple of types of regulators used .
linear. with this type , the dc input voltage must stay higher than the regulated vout to maintain regulation.
effeciency is around 60%
smps. this type varies either the frequency or pulse width of a oscillator driving a xformer.
due to the high frequency ops, filtering components can be smaller . it uses more overall components than a linear supply. but , has effeciency ratings above 90%.
it does not require an isolation xformer as that is part ot the supply
qrz
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These monitors don't require an isolation transformer. :dunno
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Does the B+ fluctuate in conjunction with the screen flucuation?
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Does the B+ fluctuate in conjunction with the screen flucuation?
Not sure, I haven't measured (Not quite sure where to do so correctly really).