computers and were only replaced when much larger
screen sizes came into the market. Today it is a different
ball game. Many monitors start giving problems after 4-5 years.
Technology may be a reason for this issue at hand. Perhaps, the
LCD or TFT technology is more susceptible to damage than the
good old tube. Perhaps manufacturers have also started to
design their products so that they no longer have an "eternal
life" to ensure that their other products sell.
Faulty design leading to heat accumulation
For this particular project of our’s, we used a Samsung 226BW
LCD monitor that was used in our testing laboratory. Four years
ago, it was the top-selling flat-screen monitors in the market.
This is because it had great value and image quality. However, a
quick look at the relevant Internet forums shows that this
monitor breaks down easily after 3-4 years. Generally it started
with flickering at first but the picture became stable after some
time. The duration of the flickers continued to grow longer in the
due course of the "exit process". After a while, the picture finally
did not stabilise at all. The guarantee and warranty period was
over and the repairs would definitely cost more than buying a
new model. In most cases, this means "End of the road -
Recycling". But it doesn’t have to come to that. We opened the
monitor in the CHIP testing laboratory and checked whether we
could identify and rectify the cause.
As the symptoms indicated a heating problem, thereby a
problem with the main power supply, we concentrated on the
power supply components and the immediate vicinity. Lo and
behold! Three electrolytic capacitors showed very suspicious
bumps on the upper side (see magnification in picture 7). This
could be caused by a few different reasons but one of the most
likely reasons is the fact that these capacitors or any other heatsensitive components were placed very closely to the heat sink.
We decided to change the capacitors on our own. Three
capacitors with a capacity of 820 ˜F (25 V) cost about RM10 and
with those in hand and soldering gun, all we had to do was
unsolder and solder six times and the monitor was back in
action again.
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