screen movement

[TheCactusKid Cactus]

Dave Andruczyk <djandruczyk at yahoo.com> wrote:

--- Frank Kumro wrote:
> I have a 19" Dell Trinitron monitor and occasionally the actual picture 
> will begin to move only a small amount from left to right but its enough 
> to annoy the hell out of me. The only time it happenes is when I need to 
> get some serious work done, anyone know what might be causing this 
> problem? Anything generic ?

(((((((((((I've seen this mainly in places with poor wiring, or too much stuff on 
one circuit. The issue lies in that the ground line (the round pin on the
plug)
and the neutral line (the bigger blade on the same plug) are differing in
voltage. The severity of the difference in potential between the two lines
causese the jitters and "jiggles" commonly seen in monitors. You can
demonstrate
it by loading down the circuit more (turn on more things.) The main current
always
flows across the hot/neutral lines, and basic electricicty theory states that 
as current goes up, so does voltage drop. In home electrical systems the
neutral (white)
and ground (green or bare) wires are ties TOGETHER in the fuse box (Also to a 
grounding rod attached to the building). On a loaded circuit the neutral which
can be 
carrying significant amperage will begine to "float" above the potential of the
ground
line, This causes issues with computer monitors and leads to the "jiggles".

Loads that have motors (fridge, dishwasher, etc..) make the effect more
pronounced if they
are on the same circuit as the computer.

A good true UPS (an "off line" one that is constantly running off the inverter)
can usually
solve this issue and cleanup the power going to your monitor. The problem is
most UPS's are
completely pass through devices until the power fails and then they switchover,
which doesn't 
help the problem..

The best solution is to move the computer/monitor to it's own circuit that
doesn't have 
any other big loads on it. (loads like incandescent lamps cause the least
problems, anything
with a motor causes the most issues. (my monitor jiggles when the fridge comes
on..))))))))))))))))))

 

Hi all, I've run into this problem all the time. Clients often have EMI, RFI, Voltage, or Circuit problems. The only way around this is to set up your equipment on it own Circuit line and hope for the best.

TheCactusKid:)

sorry for such a long winded response... :)



=====
Dave J. Andruczyk

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