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chuck chuck is offline
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Default Toshiba TV won't turn on after power outage

On Thu, 7 Apr 2011 12:00:13 -0700 (PDT), spamtrap1888
wrote:

On Apr 6, 9:22*pm, Sylvia Else wrote:
On 7/04/2011 12:39 PM, spamtrap1888 wrote:

The weather was beautiful all day -- just the typical Pacific Gas and
Electric service interruption, so it's hard to figure how it could
have been zapped with a surge. Something squeals when the set is
plugged into the power strip, but that's the only response.


Any ideas where to start?


Is there likely to be a reset button or blown fuse? It's a Toshiba
27AF43, if that's any help.


Can't help regarding repairing it, but you could try to find out from
Pacific Gas and Electric why the interruption occurred. Surges don't
necessarily come from lightening. For example having a high voltage
cable break and land on a lower voltage cable could cause one.

Whether you'd have any redress against the power company if it turns out
there was a surge would depend on your jurisdiction.


A good thought.

My local TV repair thinks the high voltage section may be damaged, but
won't speculate as to the cost of repair until I bring in this 90 lb
set and pay a $25 estimate fee.

I found a service manual online that I didn't have to sign my life
away to download. There is a fuse, but it is in series with a 1.5meg
resistor across the AC input. I measure the ohmmage across the power
cord and voila! 1.47 megohms or so. So the fuse is not blown.

Can anyone agree that there must be something wrong with the high
voltage, and speculate how extensive/expensive fixing it might be?

The squeal is probably coming from the switched power supply with a
dead short at one of its outputs. Probably a shorted horizontal
output transistor. What caused this transistor to short can be
anything from a broken solder connection, or an open electrolytic or
hv capacitor, to a shoted yoke or ho transformer. Chuck