"Dave D" writes:

"Van Chocstraw" wrote in message
...
I've got a Dell Ultrascan 1000HS Model D1025TM that was manufactured in
May of 1998. It's quite similar to the Sony CPD-200GS (17" Trinitron
tube) without the audio. I'm the original owner and have had no problems
with it for 7 years until last week. The picture was fine, no shaking, no
blurriness, warm-up time around 20 sec., no dimness, no strange sounds,
nothing. It was perfectly fine.

All of a sudden last week I turned it on one day and after about 10
minutes the screen went black. There was no change in the picture before
this happened. At the same time the picture went black the green light on
the power button also went out. It didn't change to amber, or start
blinking. I did hear a relay click out, as is normal when you shut it
off.

About 3 or 4 seconds after going black, it seemed to go into its initial
power-on startup sequence again. The degaussing relay kicked in, I heard
the static hum, then the other realy clicked, the green light on the power
button came on, the degaussing relay dropped out and it seemed to be
warming up again. But instead of completing the startup sequence, after
about 5 seconds the green light went out again and I heard the relay click
out again. This cycle then repeats itself over and over. At power-on, 3
relay clicks and the light comes on, then after a few seconds the green
light goes out simultaneously with a relay click. Lather, rinse, repeat.

If left off for an hour or so it will power on normally and display its
usual crisp, clear picture. There are absolutely no defects in the
picture. Brightness, contrast, changing screen resolutions on the PC
(800x600, 1024x768, 640x480) all work normally and the picture is fine.
But after it warms up, *click* and the light goes out and the
startup-shutdown cycle starts again.

I unplugged the video cable from the PC to see how the power-on self-test
would go and it came up normally with the "No Video Signal" message and
the color bars, so that test passed.

I'm trying to decide what to do.

There are some *lethal* areas inside a monitor, especially the mains side
reservoir capacitor, and some *painful* areas, like the CRT anode and focus
supplies, which may result in severe involuntary muscle contractions causing
serious injury or further electroction.

If you are competent to go inside with the power on-

Arm yourself with a can of freeze spray and a hair dryer/heat gun with a
small nozzle. From cold, power up the monitor and see if carefully heating
any section of the circuitry narrows the fault down. When it shuts down, try
cooling each component in the area and try powering back on until you find a
thermally defective semiconductor or capacitor.

Failing that, personally I wouldn't recommend spending money on repairing a
7 year old 17" monitor, it just isn't worth it IMO.

I'm using exactly that monitor now. It's a great monitor.

Given your symptoms, I'd first suspect a bad connection in the AC input or
power supplies, or just a loose power cord. In my experience, these are
very reliable monitors. The only problem I've seen among three of them was
a dried up capacitor in the vertical output which resulted in only half a
picture.

Do follow the safety advice though!!!

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