PDA

View Full Version : Monitor Interference



Driftwood
01-08-2008, 08:41 PM
Does anyone know of an easy way to stop an adjacent power meter box from interfering with a CRT PC Monitor.
It gets an intermitant quiver, possibly from ripple control.
This is a house situation.
The owner dosent really wont to shift it as it fits in quite nicely where it is.

tweak'e
01-08-2008, 09:07 PM
you sure its from power interference ?

have you tried it elsewhere ?

while i doubt it ripple control, electromagnetic fields from incoming power lines are a possibility. easy fix is to shield it with steel.

Driftwood
01-08-2008, 09:19 PM
Yes it's definately from the meter box.
If you move it, it's ok. (the monitor I mean)
Trouble is it's built into a very tidy wall unit.
"Steel" meaning?
I did try placing a steel oven tray behind it but didn't seem to change.
Someone suggested a lead sheet, but thats getting serious.

tweak'e
01-08-2008, 10:55 PM
oven trays is not a bad idea tho you would need to cover a fair bit of aera.

just make sure its not coming in via the lead, poor lead or lead to close to the power wires in the wall.

did you try another monitor ? just make sure its not a fault in the monitor or pc.

Driftwood
02-08-2008, 02:06 PM
Just trying a larger oven try now & does seem to have reduced it.
Was the same on another monitor & another PC in that same situ.
There is another PC in the adjacent corner shearing the same power & it' ok.

Agent_24
02-08-2008, 04:37 PM
Get an LCD monitor

Driftwood
02-08-2008, 05:03 PM
Yea well that was always an option, probably be cheaper than a sheet of lead too.

Billy T
02-08-2008, 08:50 PM
Lead won't fix it, nor will aluminium. You need to enclose the monitor in a ferrous metal shield to allow the field to divert past the monitor, locate it at least 1.5 metres away from the meter box or get an LCD monitor. Thin metal won't work, multiple layers of special grades of steel are needed for effective shielding.

If none of the above options is acceptable, remedying monitor interference is/was one of my business activities and I have a few spare monitor shields here that are now redundant due to the popularity of LCDs.

PM me if interested in obtaining one at a fire-sale price. I have shields suitable for 17" and up to 21" monitors. Some are used and extra cheap. They are heavy, but they work.

Cheers

Billy 8-{)

Just for the record, the interference does not come in via power wires or other leads. The interference is cause by direct interaction between the 50Hz magnetic field from the power meter and the scanning coils & electron beam. It is rarely the cables unless you have seriously unbalanced 3-phase power or an open neutral.

Driftwood
03-08-2008, 12:30 PM
Than you Billy T
That is exactly the information I was after.
Seeing this is situated within 300mm of the meter box, the LCD option might be the way to go.

Billy T
03-08-2008, 10:11 PM
Than you Billy T
That is exactly the information I was after.
Seeing this is situated within 300mm of the meter box, the LCD option might be the way to go.


Glad to have been of assistance.

Another series of myths put to bed.

Cheers

Billy 8-{)