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Ian Ian is offline
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Default Daewoo TV startup problem


"Neilish" wrote in message
...

Before I removed the HOT I checked to see if there was ~132v between the
C and E and there was no voltage present between any of the three pins,
is this just a symptom of the HOT failure - power supply not coming up /
regulating?

the power supply is trying to come up but since the hot is shorted it is
shutting down due to overcurrent protection
does the b+ (voltage at the collector of the hot) come up to around 130v
with the hot removed?


Yes B+ at the collector is okay with HOT removed.

I've found three fusable resistors that all check out ok, a 60w bulb in
series with the mains lead glowed bright with the HOT in place and still
glows bright with the HOT removed. Does this mean that there is still a
short somewhere and where should I look?


does the bulb dim after a while - this could just be the degauss circuit
it takes a while to switch off with a series bulb


The bulb dims after a few minutes with the HOT removed, but did not dim with
it in. I'm only using a 60w bulb at the moment, from what I've read I
should be testing with a ~150w bulb for a 28" CRT with the HOT replaced, is
this right?

check the high voltage rating capacitors around the area of the hot and
flyback for incorrect capacitance opens or shorts (out of circuit) also
check for arcing at the flyback or around the connections to the yoke -
these things can blow the hot or sometimes it just gets tired!


I've ordered a replacement HOT, which should be here Tue/Wed, and I'll start
checking the components around the HOT in the meantime. Is it safe to
assume that the LOPT is okay as there were no blown fuses.

Thank you for the reply,

--
Ian