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Sony TV troubles and Discharging CRT (with Pictures)

W

Will

Jan 1, 1970
0
Hi,

Obviously, any advice you do give is at my own risk, and you will not
be held responsible for any accidents that could occur.

To give you an idea what level of understanding I have, I'll give you
some background.
This is the first time I've taken the back of a TV. I've previously
successfully fixed washing machine electrics, I'm a qualified car
mechanic so I've dealt with LT and HT problems + radios, electrical
systems etc and I've got a Physics A level.


So, on with the problem:

We were watching TV (Sony KV32FX U) yesterday (Lost, what a silly
ending that was) and everything was fine, good picture etc, when
suddenly, the TV clicked loudly and the picture disappeared. Now, if
I push the power button to on, the standby button lights correctly. If
I then press a channel button to actually try and show as channel, the
TV clicks (it made this sound when it worked correctly), but no
picture or sound come and the standby light flashes 4 times.

I've taken the back off, and checked the one fuse I could see (ok).

Any thoughts on what the problem could be?


In addition, regarding safety:

I've used the following procedure to attempt discharge the CRT (power
disconnected)


"Either purchase a shorting probe or make one. If this is not an
option, use two well-insulated screwdrivers.

If using a probe, connect the wire and clip to the metal chassis
surrounding the CRT. If using screwdrivers, place the end on one
screwdriver on the metal chassis surrounding the front of the tube.

NOTE: Make absolutely sure that you are not touching any metal parts
during the next steps.

If using screwdrivers, slip the end of the other screwdriver under the
protective rubber grommet on the side of the CRT, where the high-
voltage wire is attached to the tube.

Note: When you discharge the tube, there may be a very bright flash
and a loud snapping noise. Try not to look at the point where the
flash will appear. Also, be aware of the snapping noise, as it may
cause you to jump.

Now, either slip the end of the shorting probe under the rubber
grommet or cross the two screwdrivers together to create a path for
the electricity to arc across.

Remove the screwdrivers or probe."



I attempted perhaps 10 times, ensuring I got the screwdrivers on the
metal.
When I did it, there was no noise, spark or flash. Does this sound
reasonable?

I've taken pictures of me doing this which you can see here:

http://www.wmathias.0catch.com.

There's also some other pictures of the TV for reference.

Any help would be much appreciated,

Will
 
W

Will

Jan 1, 1970
0
Also, can recommended reading on the subject would be very helpful
 
Hi,

Obviously, any advice you do give is at my own risk, and you will not
be held responsible for any accidents that could occur.

To give you an idea what level of understanding I have, I'll give you
some background.
This is the first time I've taken the back of a TV. I've previously
successfully fixed washing machine electrics, I'm a qualified car
mechanic so I've dealt with LT and HT problems + radios, electrical
systems etc and I've got a Physics A level.

So, on with the problem:

We were watching TV (Sony KV32FX U) yesterday (Lost, what a silly
ending that was) and everything was fine, good picture etc, when
suddenly, the TV clicked loudly and the picture disappeared. Now, if
I push the power button to on, the standby button lights correctly. If
I then press a channel button to actually try and show as channel, the
TV clicks (it made this sound when it worked correctly), but no
picture or sound come and the standby light flashes 4 times.

I've taken the back off, and checked the one fuse I could see (ok).

Any thoughts on what the problem could be?

In addition, regarding safety:

I've used the following procedure to attempt discharge the CRT (power
disconnected)

"Either purchase a shorting probe or make one. If this is not an
option, use two well-insulated screwdrivers.

If using a probe, connect the wire and clip to the metal chassis
surrounding the CRT. If using screwdrivers, place the end on one
screwdriver on the metal chassis surrounding the front of the tube.

NOTE: Make absolutely sure that you are not touching any metal parts
during the next steps.

If using screwdrivers, slip the end of the other screwdriver under the
protective rubber grommet on the side of the CRT, where the high-
voltage wire is attached to the tube.

Note: When you discharge the tube, there may be a very bright flash
and a loud snapping noise. Try not to look at the point where the
flash will appear. Also, be aware of the snapping noise, as it may
cause you to jump.

Now, either slip the end of the shorting probe under the rubber
grommet or cross the two screwdrivers together to create a path for
the electricity to arc across.

Remove the screwdrivers or probe."

I attempted perhaps 10 times, ensuring I got the screwdrivers on the
metal.
When I did it, there was no noise, spark or flash. Does this sound
reasonable?

I've taken pictures of me doing this which you can see here:

http://www.wmathias.0catch.com.

There's also some other pictures of the TV for reference.

Any help would be much appreciated,

Will

usually horiz output or psu. Can be many things though. You'd need
electronics skills to do it.


NT
 
A

Art

Jan 1, 1970
0
No comment on the physics and automotive ability but you may be far wiser to
relegate this device to the professionals who are specifically trained in
their repair of Sony Specific Products. It may be far safer and less
expensive in the long run for you. Also the specific devices you will need
for repair willl probably need to come from SONY or their parts depot.
Cheers
 
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