Page 58 - Testing Electronic Components

Now is the time to share my true
case example- a computer dealer
send me a monitor for repair with
power blink symptom. Usually I
do not straight away repair the
monitor but I would first use the
flyback tester to scan all the
major coils (switch mode
transformer, flyback transformer,
B+ coil and horizontal deflection
coil) before using my digital or
analogue meter to do testing.

When measuring the B+ coil, the
Led lights went off and it suppose
to show at least 5 LED bars and
above. Upon soldering out the
coil, I did not see any burn mark
at the winding or loop and in fact it looks shiny. Because I trust the
meter, I opened up the winding and to my surprised the internal
winding had burnt into crisp but the outer winding looks good
indeed! A new B+ coil restored the monitor to life.

By using a flyback tester or coil tester for testing coil, it has helped
me to locate many shorted coils in switch mode power transformer
primary winding, B+ coil, flyback transformer primary winding
and horizontal deflection coil. The flyback meter can even be used
to check the condition of ballast in fluorescent lamp too!

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