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Yukio YANO Yukio YANO is offline
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Default Moire effects on new TV

svu geek wrote:
What would be causing a Moire effect on a new CRT SDTV? There are
smally wavy lines that appear on the middle sides of the tv. I'm
pretty sure they're moire effects. They only appear in a spot that's
maybe 2-3 inches in diameter.

The tv is a 27" flatscreen that's 480i. The tv is connected to the VCR
via coaxial cables and the VCR is then connected to the digital cable
box via coaxial cables. The cable signal/reception isn't all that
great and I get horizontal wavy lines on some analog channels. I think
the moire effects also appear when watching a dvd through composite
cables.

There are no signs of electrical interference.

Even though the tv is a flatscreen, it seems to cave in a bit on the
sides. Older CRTs caved out on the sides.

Do the moire effects mean the tv is defective? Is it something that
will get worse with time? I suppose I want to know if it should be
returned? It doesn't bother me as I hardly notice. I just don't want
to get stuck with a defective tv.

Degaussing Problem ???
Because it appears in a spot about 3" in diameter
This is a LOCAL problem affecting Convergence , on a small percentage of
the Screen
Unplug the set off for about 10-15 minutes then turn back on ! Repeat
several times to allow the built-in Degaussing circuit to cycle several
times. You have to let the Thermistor in the Degaussing circuit Cool
down, between restarts
Moire effects are usually caused by AC fields.
Look around for the source of the magnetic field, transformers, fans,
motors. powerpacks and chargers, speakers.

If all else fails return the set !

The Barrel Distortion may be an Optical illusion. ie. Barrel distortion
on older CRTs' and Pincushioning on Flatscreens even after correction.

Yukio YANO