Digimate TFT backlight switches off after 2 seconds

I have a 17" digimate tft that was fine until i started using it with
my laptop as an extended monitor.
Now the backlight comes on whenever a change is made to the display
properties or if the monitor is switched on, but then after a couple of
seconds it switches off. Previously I found that eventually it would
stay on but could not figure out what was causing the problem. Now it
swtiches off every time even when connected to a pc as the primary
monitor. I have checked the laptop and other monitors work fine with
it.
The monitors is only about 2 months old.
Any Ideas???

zcftl11@hotmail.com wrote:
> I have a 17" digimate tft that was fine until i started using it with
> my laptop as an extended monitor.
> Now the backlight comes on whenever a change is made to the display
> properties or if the monitor is switched on, but then after a couple of
> seconds it switches off. Previously I found that eventually it would
> stay on but could not figure out what was causing the problem. Now it
> swtiches off every time even when connected to a pc as the primary
> monitor. I have checked the laptop and other monitors work fine with
> it.
> The monitors is only about 2 months old.
> Any Ideas???
>

Monitors use cold cathode fluorescent lamps (CCFL) and a high
voltage inverter. The high voltage inverter is able to supply
only a couple of milliamps to the lamp. If the inverter is overloaded
for any reason, that can cause the inverter to switch off.

(Inverter and CCFL lamp, for an LCD monitor)
http://www.anok.ceti.pl/inverter/inverter1.jpg

The only user control you can experiment with, is change the
intensity setting of the screen. That may be accessible via
the OSD (on screen display) interface on the monitor. You may
not be able to see what you are doing, which will be the hard
part. Sometimes, if you drop the screen intensity, that changes
the output setting for the inverter. The inverter is asked
to produce less current, and the inverter will stay on for
longer. (The OSD display setting, drives a signal to the inverter,
and that signal is what tells the inverter how much voltage to
produce. Turning down the screen intensity, means the inverter
doesn't have to work as hard.)

If reducing the screen intensity makes the screen stay on, then
you know that eventually the inverter will stop entirely. This
workaround tells you the problem is with the inverter, and
whatever problem the inverter has, will only get worse with time.

Sometimes, it is a bad connection between the inverter and the
lamp. There is a cable and connector of some sort. Some people
find that replugging the cable inside the monitor will make
it work for a while.

Exact replacement parts for the monitor, would be the best
way to repair it. If the monitor is 2 months old, and the
monitor had a one year warranty, you should use the warranty
to get it fixed. It will be a lot harder to find a good
replacement lamp or inverter, by shopping for it on the
Internet. Whoever manufactured the display, will have a
supply of proper replacement parts.

Paul

Thanks a lot for the detailed response.
I will look into the connection check for any damage as I have moved
the monitor about a bit

I have recently had a similar problem with 17" Digimate monitors. We
have 120 of them, each day more and more develop the same problem.

I have found that it is the power supply that is at fault.

Call Digimate on 08712508000 and ask them for a replacement power
supply.

Hope this helps.

My DIGIMATE 17" FTP monitor flickers uncontrollably - mainly whilst in
Windows XP but sometimes when accessing the System BIOS Screen. I
connected the monitor to different PCs and the same thing happens. The
problem may surface during booting up although there were times when
the flickering/frazzling started 30-60 minutes later.

Could this problem be related to the fault reported here?

seraphim_2000@hotmail.com wrote:
>
> My DIGIMATE 17" FTP monitor flickers uncontrollably - mainly whilst
> in Windows XP but sometimes when accessing the System BIOS Screen. I
> connected the monitor to different PCs and the same thing happens.
> The problem may surface during booting up although there were times
> when the flickering/frazzling started 30-60 minutes later.
>
> Could this problem be related to the fault reported here?

What's an FTP monitor? At any rate, you may have dust inside,
causing the CRT high voltage to arc over. Try blowing it out.

--
Chuck F (cbfalconer at maineline dot net)
Available for consulting/temporary embedded and systems.
<http://cbfalconer.home.att.net>