Friday, June 29, 2012

Randy - Samsung 226BW monitor flickering fix


I enjoy doing outdoor things with the family like camping, biking, and hiking.  I like to go hunting, but so far just take Colin hunting.  I enjoy running to stay in shape and keep from getting old - I don't think it's completely working though.  I enjoy accompanying the kids on guitar when they play fiddle tunes.  We have a good time.  I also enjoy programming and electronic circuits.

Today's post is about our computer monitor (Samsung 226BW) that recently started flickering.  First it was only flickering for half a minute when the monitor came out of sleep.  I got around that by changing the setting on the computer so that it doesn't put the monitor to sleep.  That worked for a week or so, but then the monitor got turned off and when we tried to turn it back on it just flickered forever and never fully turned on.  The monitor still showed the picture, but it wasn't very bright and it made me sick to try to use it so I just used the laptop instead.

A Google search showed that this is actually a common problem for this monitor and the typical solution is to replace some capacitors.  I decided to open up the monitor and see what condition the capacitors were in.

First, I just three screws out of the back to remove the base and three more followed by some easy prying with a screwdriver to get the back black plastic cover removed.

Then I pried the left sheet of metal up at the tabs to pop it off.

I unhooked the wires from the bottom left and the bottom right so I'll be able to lift up the cover.

With the cover lifted, now I see two boards.  The one on the left is the one with the power supply (where the power cord connects), so I need to unscrew that one to see the capacitors.

There was also a small sheet of metal at the top of the left board that needed to come out before the board would pull out.

There they are.  And now for a closer look...

These three capacitors are no longer flat on top like they should be, so they'll need to be replaced.  The two on the left are 820uF capacitors.  The one on the right is a 330uF capacitor.

Looks like this one needs to be replaced too.  It's a 680uF capacitor.

And its companion behind it of the same size also needs to be replaced.

Look at that.  This one looks good and won't need to be replaced.  It's 47uF.

And this big one looks good too.

So the capacitors I need to replace are:
one 25V 330uF 105C capacitor
two 25V 820uF 105C capacitors
two 25V 680uF 105C capacitors

The 47uF capacitor is 50V 105C, but it doesn't need to be replaced, and neither does the big 450V 150uF capacitor.

If I were patient, I'd order the capacitors and just install them when they arrived, but I'm not very patient.  I tried to find some locally at Radio Shack, but they didn't have any high temp (105C) capacitors, let alone the right capacitance.  I found a local electronics parts store called The Current Source.  The guy I talked to there has a 330uF 50V 105C capacitor and some 1000uF 25V 105C capacitors.  While reading other forums, I found plenty of people have used 1000uF instead of 820uF with success.  For power supply usage, the exact capacitance doesn't seem to matter as long as it's not less than the original, and the same goes for the voltage.

So I bought four 1000uF 25V capacitors and one 330uF 50V capacitor for $7.60.  The 1000uF capacitors are about the same size as the original 820uF capacitors, but the 330uF 50V capacitor is quite a bit larger because it's 50V.  It still fits on the board though.

This picture is after removing the 820uF capacitors and the 330uF capacitor and installing one of the new 1000uF capacitors.  The circle on the board has slanted lines in the negative half of the circle showing where the capacitor goes.  The capacitors have a band on them with a negative sign indicating which lead is the negative one.  Also, the negative lead is shorter than the positive lead.

 Here's the board with all the new capacitors installed.

I just put it back together and plugged it in to try it out.  It's working great!  A fun way to save $200!

1 comment:

  1. Great job, Honey! I love having a working monitor again. Thanks!


We appreciate your respectful comments and feedback.