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Mike Coon[_2_] Mike Coon[_2_] is offline
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Default 22" monitor GNR TS2200WA - info?

In article t,
says...

In article ,
says...

I've prized the case off and got sight of the two boards; one power and
one logic. Both well provided with component annotations, even for the
jumpers, but of course I don't have a schematic. Boards are connected by
a cable that, it says, supplies +5V and has one sense "ADJ" line and one
"On/Off" line. Quite like a PC or no doubt lots of other appliances
which have a low-power standby state. The power supply is marked that it
supplies +5V, and "optionally" +24V, +12V and -8V.
Measuring, the +5V started at ~3V and worked up to a rather wobbly 5V.
Must stick a 'scope on the wobbles to see if I can spot a pattern. The
"ADJ" line also varied ~2V / ~3V. But clicking the power switch made no
difference to the +0.1V on the "On/Off" line.



Did you see this youtube about the monitor ?

I think I would start out just replacing the electrolytic capacitors on
the power board.

Many switching supplies seem to have blown capacitors. I have repaired
several items around my house by replacing capacitors.

One give away for me is to take the heat gun of my hot air rework
station and playing it around one or two capacitors at a time. If the
set starts working or manking a big change I replace them.


The heat gun I have is a paint stripper. I use it a lot to shrink heat-
shrink tubing but am reluctant to play it on electronics. And I cannot
find the non-contact thermometer I was sure I had.

Viewing the youtube video I think was meant, I see the same capacitors
have bulges in my power supply. So though I cannot pop down to my local
Maplin (like the youtuber) because they have since gone out of business,
I have ordered replacements, fitted three, and the monitor is now
working!

It is sad that a board clearly marked 2007 already has multiple duff
components (assuming they are duff). I notice that the bulgy capacitors
have cross-scores on the flat end, almost like a hot-cross bun. The
scores recall a burst diaphragm, so I wonder if they are a safety
feature for components which are considered quite likely to fail
explosively! The words written on the items include "VENT", which makes
me think that I might be right...

As well as three bulging capacitors there are three flat-ended ones
which are also scored, so I hope those are "good".

I do not have an ESR meter but have noticed many discussions of such in
this NG over the years...

Thanks to all respondents.

Mike.