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Arfa Daily Arfa Daily is offline
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Default More strange LCD distortion ...


"Meat Plow" wrote in message
...
On Mon, 9 Nov 2009 01:09:59 -0000, "Arfa Daily"
wrote:

Following on from my slightly OT post of a few weeks ago regarding the
'impossible' H linearity error that I saw on the Delta in-flight LCD
screen,
tonight, I saw another. This time it was on an LCD screen at my local
bingo
hall. I would guess that it's about a 22", standard 4:3 aspect ratio. Used
to display numbers when they are playing tabletop cash bingo, and winning
cards during normally called bingo. There are many screens around this
large
hall, all being fed from the same primary video source, so I think that
incoming signal can be eliminated.

This one had a 'foldover' of about 1.5" at the top left corner. It
progressed across the screen getting less and less, until at the right
hand
side, the top of the picture was absolutely normal. The 'foldover' was
extremely non linear. It looked to be very stretched, to the point where
you
could see what you would describe as individual scanning or field flyback
lines - if it were a CRT display ...

I thought I was reasonably au fait with the way an LCD screen was driven
from its frame buffer, but I'll be buggered if I can see a way that data
could be read out erroneously, in such a way as to produce a badly
stretched
tapering wedge of foldover, across the top of the screen. Anyone seen
anything like *this* one, or have any suggestions how it could occur ...
??

Arfa


Its as if the signal was distorted before it ever got to the LCD.
Isn't that possible?


Hi Meat. See reply to Adrian above. Here's a little aside you'll no doubt
find amusing ... Got in this afternoon, and number 2 daughter was doing some
door painting for us in the house, and had MTV on. At pretty near full
volume, shaking the house ...

Tonight, I'm watching some TV, and the sound is 'wrong'. A bit quiet, and
slightly 'thin' sounding. Then some incidental music came on the programme,
and it had a very odd 'raspy' sort of a sound to the bass beat. Then I
realised what is wrong. She's only gone and buggered the TV set's built in
sub. Bloody kids. Who needs 'em ?

Arfa