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klem kedidelhopper klem kedidelhopper is offline
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Default Sony model number KDS-50A2000 green haze

On Jan 11, 12:24*pm, Jeff Urban wrote:
I think we need a think check here. I looked up that model on Google
and found this :

"3 SXRD chips (R/G/B), Over 2 Million Pixels each. "

Now that seems to indicate that it is an LCD, but could actually be a
three chip DLP, I didn't get that far. However in either case that
means that there is no color wheel.

Obviously then there are dichroics to separate the colors. If it is a
three chip DLP there is a good chance of maybe fixing the light engine
because you might find one in scrap somewhere that was canned for
another on many possible problems.

However from what I've seen polarizing filters go bad in LCD units,
probably partly due to heat, but maybe just due to the sheer volume of
light passing through. In either case I have been through the
possibility of actually replacing a polarizing filter. The problem is
the orientation.

Here is the main question, can it modulate the green ? Let me clarify,
does it look like a set with an HK short in the green with a weak
green gun ? i.e., if you turn the brightness all the way down it is
green and if you turn it up it goes magenta ? If that is the case it
is probably the green polarizing filter.

However if the white is actually white, it might be somethng else. The
set is said to use SXRD chips. I am not sure if that is DLP or LCD
really. There is no reason they can't use three DLP chips, although
the only reason I can see is for better response time. And that set
has it, 2.5mS. However it does seem that a three chip DLP would be
even better.

If it is a polarizing filter, you can buy that material. However you
must have at least a little piece of it from the original intact to
determine the orientation as it is impossible to do it by trial and
error. A thread a few years old outlines this, pertaining to a Zenith
D something WLCD. Eithr D60WLCD or D52WLCD, something like that.

One day I will tear into one, but not until someone is wiling to pay
for it. If I spend a day on somethng like this and can't pull in at
least $300 the boss will have a heart attack. And it would take time
for sure.

Alot of this is supposition, but one thing is for sure, the set is a
three chip, therefore there is no color wheel. And anyone who wants to
tear into me pointing out that it might be LCOS, I remind you that
LCOS IS LCD.

J


I've done some further investigating of this problem and have found
that it occurs due to a poor design of the optical block. The heat
causes the filters to distort and dust that gets into the assembly
because it's not sealed gets burned into the plastic as well. Your
basic **** design. This is 300.00 to the trade for the rebuild, and
since the original problem was never really resolved, after the repair
one can expect to repeat it again after 2 or 3 years. And this
information comes right from a light engine rebuilder. I can hear this
dog barking from a long way off. Lenny