[TenTec] Orion LCD screen darkening

[Steve N4LQ]

I tend to believe the dark areas are a quality issue. My reasoning is:
A. Only some displays have the problem. (Mine did not).
B. One must have a B. to sound intelligent.
Mine took a long time, 30 minutes, to completely warm up to where the
contrast was stable. As it warmed up, the contrast would vary from milky
looking to sharp. I assume the long warm up time is not so much waiting for
the back-light to get brighter but rather for the crystals to become warm
enough to block the light from the back-light.
The Icom series of LCDs take about 5 minutes warm up but they seem to start
out with low brightness and get brighter instead of  low contrast like the
Orion's display. The Icoms seem more consistent with typical computer LCD
displays and they react to temperature.
I really don't think excessive is the root problem here. Perhaps the extra
cooling from a fan helps compensate for the defective LCD.
Steve N4LQ
----- Original Message ----- 
From: "Ken Brown" <ken.d.brown at verizon.net>
To: <tentec at contesting.com>
Sent: Friday, September 17, 2004 8:15 PM
Subject: [TenTec] Orion LCD screen darkening


> Hi all,
>
> I am not an Orion owner, nor have I had the opportunity to operate one.
> However I have read a lot of the posts regarding various virtues and
> faults in the Orion. The "screen darkening" has been mentioned often
> enough in unemotional postings, that I believe it is a problem that
> really exists in many of the Orions. I have seen the addition of a fan
> mentioned as a cure for this problem. Since the darkening is not uniform
> across the whole display, it occurs to me that the cause of the problem
> is not only excessive heat, but also non-uniform temperature across the
> display. I wonder if either instead of or in addition to adding a fan,
> it might be worth while to place a highly heat conductive plate behind
> the LCD panel. The plate would conduct heat such that the temperature
> would be more uniform across the back of the display. Some insulation on
> the opposite (from the display) side of the conductive plate might help
> also. This could simply be a piece of copper clad printed circuit board
> material, with dimensions equal or larger than the display panel. If it
> is single sided PCB material the copper side would be closest to the
> display panel. Maybe double sided would be even better. Since I have
> never seen an Orion, I do not know whether there is room for such a
> plate, or an easy way to attach it to the back of the display. Just a
> suggestion.
>
> DE N6KB
>
>
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