Hello, Looking to get my favorite monitor back up and working away again.
I had been using it non stop for a few years, and just before I had to move,
I went through a period of about a week where after it would be on for maybe
an hour, the blue gun or signal would just drop out. I could immediatly power
it off, turn it back on and the blue signal would be back, but then would cut
out again in a few minutes. If I let it fully cool down, I could maybe get an
hour out of it. Jump ahead a year later after it was in storage. It still has
the problem, although last night I timed how long until it would drop out, and
it lasted about 4.5 hours. Let it sit turned off most of today, and it's
running just fine now for about 3 hours, but I suspect the drop is coming.
I had opened it up about 3 months ago, the main board was dusty, the usual
stuff. Took a can of dustoff and a small vacuum cleaner to it, so at least now
the insides look nice, but are still taking a dive. I don't know the vintage
of the monitor, picked it up surplus from Seagate in about 2002, they must
have had a few years prior (they are very good at getting brand new gear
every year and surplusing everything else out..)
I'm taking a wild stab and thinking it might be some caps that have
aged out. There's a surprising lack of great numbers of components on the
mainboard, so I'm not nervous about just changing them all out. Just wondering
if anyone out there has had the same symptoms, or have seen this in any
service doc's as a known problem.
And last: If anyone has a copy of the service manual/schematic that
they be willing to sell a copy of, I'd be interested.
Please reply to this newsgroup or leave an email address and I will
send a reply.
Thanks!

D.

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Use a heat gun, and freeze spray on all the components in the power supply,
and scan areas to start with. The work your way through the video path. You
can try working in sections to start with. Eventually, you should get it
down to the component that is the cause. The fault may be a cap, or any
other type of component that became temperature sensitive. Don't rule out
cold solder connections, and the possibility of the CRT itself becoming
intermittent. I have seen all kinds of things cause thermo problems.

--

JANA
_____


"DougD" wrote in message
news:cwCEf.421616$2k.345184@pd7tw1no...
Hello, Looking to get my favorite monitor back up and working away again.
I had been using it non stop for a few years, and just before I had to move,
I went through a period of about a week where after it would be on for maybe
an hour, the blue gun or signal would just drop out. I could immediatly
power
it off, turn it back on and the blue signal would be back, but then would
cut
out again in a few minutes. If I let it fully cool down, I could maybe get
an
hour out of it. Jump ahead a year later after it was in storage. It still
has
the problem, although last night I timed how long until it would drop out,
and
it lasted about 4.5 hours. Let it sit turned off most of today, and it's
running just fine now for about 3 hours, but I suspect the drop is coming.
I had opened it up about 3 months ago, the main board was dusty, the usual
stuff. Took a can of dustoff and a small vacuum cleaner to it, so at least
now
the insides look nice, but are still taking a dive. I don't know the vintage
of the monitor, picked it up surplus from Seagate in about 2002, they must
have had a few years prior (they are very good at getting brand new gear
every year and surplusing everything else out..)
I'm taking a wild stab and thinking it might be some caps that have
aged out. There's a surprising lack of great numbers of components on the
mainboard, so I'm not nervous about just changing them all out. Just
wondering
if anyone out there has had the same symptoms, or have seen this in any
service doc's as a known problem.
And last: If anyone has a copy of the service manual/schematic that
they be willing to sell a copy of, I'd be interested.
Please reply to this newsgroup or leave an email address and I will
send a reply.
Thanks!

D.

--

In article , "JANA" wrote:
Use a heat gun, and freeze spray on all the components in the power supply,
and scan areas to start with. The work your way through the video path. You
can try working in sections to start with. Eventually, you should get it
down to the component that is the cause. The fault may be a cap, or any
other type of component that became temperature sensitive. Don't rule out
cold solder connections, and the possibility of the CRT itself becoming
intermittent. I have seen all kinds of things cause thermo problems.


I did try using the cooling spray on it while it was in the state of the blue
channel just having dropped out, no results. But to do it properly, I should
go back and try using the heat gun to see if I can force it into that state by
localising the defect. And being that it is a fairly sparse boards, it won't
be a big problem to reheat any of the solder joints. It's just been a bit of
lazyness on my part as it's a rackmount unit and it's a bit of pain to pull it
out, and I have 4 other monitors of the same family to fall back on, so it's
never been a situation of being completely down...yet...
Thanks again for the good advice, and reminding me about trying the
heat gun. I've had one situation where I was using the heat and cool method
and the heat provided just enough energy to cause a catastophic failure in a
large passbank laser power supply, so I suspect I may be a bit "gunshy"..
Well, now to go search out some canned cold. I'm up in British Columbia,
and since moving here from the US a few years back, it kills me when I see
what they get for stuff like that here. A simple can of low quality dust off
goes for $12-17 here, just insane.. On the other hand, in the few moments
when I look up from the monitors, I'm looking out at mountains and ocean
that looks like something from Natl. Geographic..poor me..wasting away
editing video..

Thanks!
Doug

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