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From: philo on 5 Aug 2010 20:10

<B__P(a)hotmail.com> wrote in message
news:1c1m56lnfmesh5siabsr62lpi3iq8uvtn9(a)4ax.com...
> I've a 22" Westinghouse LCD Monitor that stopped working from one day
> to the next. The light the normally comes on when the monitor is on
> doesn't even light up. Could it be that a fuse has blown on the
> inside? Maybe one I could replace? Or perhaps the on/off switch
> has gone bad. If anyone can provide a credible reason it stopped
> working and a possible fix, I'd be most grateful.
>
> BP


Not likely


From: John Doe on 5 Aug 2010 20:23
Winniethepooh 100acrewoods.org (GMAN) wrote:

> if every capacitor in the unit is needing replacement, it most
> likely wont cost you more than $10-$15 for those parts.

But seriously. That is neither here nor there.
--





















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> Newsgroups: alt.comp.hardware.pc-homebuilt
> From: Winniethepooh 100acrewoods.org (GMAN)
> Subject: Re: Monitor will not turn on. Does it have a fuse I can change?
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From: Paul on 5 Aug 2010 22:29
B__P(a)hotmail.com wrote:
> I've a 22" Westinghouse LCD Monitor that stopped working from one day
> to the next. The light the normally comes on when the monitor is on
> doesn't even light up. Could it be that a fuse has blown on the
> inside? Maybe one I could replace? Or perhaps the on/off switch
> has gone bad. If anyone can provide a credible reason it stopped
> working and a possible fix, I'd be most grateful.
>
> BP

It helps if you have a model number to work with. The following
is just an example I made up for myself :-)

*******

I can't see a fuse here. Just a moderately dangerous open-face
assembly to work on (yellow PCB).

http://www.ccl-la.com/blog/index.php/repairing-the-westinghouse-lcm-22w3/

http://i.ebayimg.com/15/!Bud)9zgCGk~$(KGrHqQOKigEvN2wjNhrBM!eFK8N2Q~~_1.JPG?set_id=880000500F

I'm guessing, signal flow, left to right, bottom half, is
AC input filter, rectify to HV DC, switching transistor on heatsink
for HV primary side DC, transformer in yellow, with turns ratio to
fix output voltage, rectifiers on heatsink (synchronous rectification,
or just plain rectifiers ?), and a bunch of filter caps for low
output voltages. Eight pin connector carries low voltages
to the adapter board (adapts DVI and VGA, to panel signals,
does scaling perhaps).

The top section includes two HV inverters, taking perhaps 12VDC
in and giving 700-1000 VAC output at high frequency, to run the
backlights. I see perhaps two optoisolators (8 pin) ? And the
three yellow things on the right could be small transformers,
not really sure what that would be for.

Depending on the era, the capacitors could be leaking, and the
unit may have managed to detect an internal overload, shutting
down the switching action.

It could have a fuse, as I can't identify every component in the picture.
For example, there is a black blob below the three pin AC plug. The
PCB assembly is really cheap, and appears to be a single sided layout,
with wire straps used on the component side, to complete the layout.
Rather than put copper tracks on both sides of the PCB, they put
most of the copper tracks on the back. When a signal needs to
jump, they use those bare exposed straps on the component side.

The supply board is made by Delta Electronics. And that particular
example is DAC-19M009. The only thing I can see on Ebay, is someone
offering to accept your power supply board, and replace the
caps for you. Even though there could be other damage to the
thing. It isn't always going to be just the caps that
are damaged. When caps fail, sometimes other components
are damaged in collateral action.

Any sizzling, smoke, or funny smells before this happened ?

The thing is, even if there was a fuse, that fuse blew for a reason.
Just replacing the fuse won't fix it. The fuse would only blow again,
until you fixed it right.

It is possible for an engineer, to use a wrong value fuse, leading
to nuisance trips. But I haven't seen a mistake like that in
eons. Most of the time, the fuse will blow, to tell you there
is a serious problem elsewhere. A problem that must be fixed
first, before you can contemplate changing the fuse.

Paul
From: Mike Easter on 6 Aug 2010 03:34
Paul wrote:
> B__P(a)hotmail.com wrote:
>> I've a 22" Westinghouse LCD Monitor that stopped working from one day
>> to the next. The light the normally comes on when the monitor is on
>> doesn't even light up. Could it be that a fuse has blown on the
>> inside? Maybe one I could replace? Or perhaps the on/off switch
>> has gone bad. If anyone can provide a credible reason it stopped
>> working and a possible fix, I'd be most grateful.
>
> I can't see a fuse here. Just a moderately dangerous open-face
> assembly to work on (yellow PCB).
>
> http://www.ccl-la.com/blog/index.php/repairing-the-westinghouse-lcm-22w3/

That's a useful description to help sell his package of capacitors.

> It could have a fuse, as I can't identify every component in the picture.

> The thing is, even if there was a fuse, that fuse blew for a reason.
> Just replacing the fuse won't fix it. The fuse would only blow again,
> until you fixed it right.

One of the comments had a fuse, the tech guy answered that there are two.

Comments 5 & 7 - the numbering system is imperfect w/ dupes

=========

# Peter Triffitt on Wed, 17th Mar 2010 4:03 pm

Hello Sirs.
What a brilliant site!! My monitor has just stopped working, no
noticable warnings.I have the board DAC-19M009 on my bench, and it all
looks in order. But I have tested the fuse (F101) and it is open
circuit, there is also a very slight area of soot between the fuse
connections. Shall I replace the capacitors anyway? Can you supply the
fuse? Or is this a different fault?
Best Regards Pete.

# CCL_TECH on Sun, 21st Mar 2010 3:55 pm

Yes, We can provide the fuse. Which fuse is blown, the one on the ac
side or the pico fuse on the bottom of the board?

=========

Further down there is more description about that fuse.


--
Mike Easter
From: Astro on 6 Aug 2010 03:44
On 2010-08-06 10:23:18 +1000, John Doe <jdoe(a)usenetlove.invalid> said:

> Winniethepooh 100acrewoods.org (GMAN) wrote:
>
>> if every capacitor in the unit is needing replacement, it most
>> likely wont cost you more than $10-$15 for those parts.
>
> But seriously. That is neither here nor there.

Where is it?

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