Went to the thrift store and looked at a TV. everything was fine for the
first five seconds or so it was on, then I heard arcs goin' off like mad.
I opened up the back and they were shooting across the back of the tube
around where an orange wire was mounted to it with what looked like an EKG
pad(medical ref.) Judging from the power source (a bunch of undersized
and ratty extension cords) It could have been not grounded or experiencing
a line voltage issue. I immediately started looking for a capacitor but
I'm an installer of HVAC equipment by trade and troubleshooting is not my
area of expertise. If anyone has a simple answer please reply. It was an
NEC w/built in dolby stereo receiver (don't have the model #, didn't get
to look long). Thanks.

"HVACguy" writes:

Went to the thrift store and looked at a TV. everything was fine for the
first five seconds or so it was on, then I heard arcs goin' off like mad.
I opened up the back and they were shooting across the back of the tube
around where an orange wire was mounted to it with what looked like an EKG
pad(medical ref.) Judging from the power source (a bunch of undersized
and ratty extension cords) It could have been not grounded or experiencing
a line voltage issue. I immediately started looking for a capacitor but
I'm an installer of HVAC equipment by trade and troubleshooting is not my
area of expertise. If anyone has a simple answer please reply. It was an
NEC w/built in dolby stereo receiver (don't have the model #, didn't get
to look long). Thanks.

The high voltage is arcing between the high voltage output connection to
the CRT, and the ground of the CRT. It's likely there is excessive
high voltage due to a regulation failure, or it's just dirty.

Nothing to do with ratty extension cords.

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"HVACguy" wrote in message
lkaboutelectronicequipment.com...
Went to the thrift store and looked at a TV. everything was fine for the
first five seconds or so it was on, then I heard arcs goin' off like mad.
I opened up the back and they were shooting across the back of the tube
around where an orange wire was mounted to it with what looked like an EKG
pad(medical ref.) Judging from the power source (a bunch of undersized
and ratty extension cords) It could have been not grounded or experiencing
a line voltage issue. I immediately started looking for a capacitor but
I'm an installer of HVAC equipment by trade and troubleshooting is not my
area of expertise. If anyone has a simple answer please reply. It was an
NEC w/built in dolby stereo receiver (don't have the model #, didn't get
to look long). Thanks.


That suction cup looking thing is an insulating cap over where the anode
lead clips onto the tube. The most common cause of arcing there is collected
dust that absorbs moisture and becomes conductive. The arcing burns it into
carbon which is even more conductive and the problem gets worse.

What I do to fix these is to discharge the tube, then clean the area around
the anode real well with simple green or something similar to get all the
grime and carbon off, and clean the anode cap as well. Then get some
dielectric grease from an automotive store (look in the spark plug section)
and smear a coat of it on the bottom of the suction cup and reassemble,
should be good as new.

That suction cup looking thing is an insulating cap over where the anode
lead clips onto the tube. The most common cause of arcing there is collected
dust that absorbs moisture and becomes conductive. The arcing burns it into
carbon which is even more conductive and the problem gets worse.

What I do to fix these is to discharge the tube, then clean the area around
the anode real well with simple green or something similar to get all the
grime and carbon off, and clean the anode cap as well. Then get some
dielectric grease from an automotive store (look in the spark plug section)
and smear a coat of it on the bottom of the suction cup and reassemble,
should be good as new.


And don`t stick your finger in the hole in the glass tube! even after
you discharged it

Ron

On Sun, 1 May 2005 11:02:19 +0000 (UTC), "Ron(UK)"
wrote:




That suction cup looking thing is an insulating cap over where the anode
lead clips onto the tube. The most common cause of arcing there is collected
dust that absorbs moisture and becomes conductive. The arcing burns it into
carbon which is even more conductive and the problem gets worse.

What I do to fix these is to discharge the tube, then clean the area around
the anode real well with simple green or something similar to get all the
grime and carbon off, and clean the anode cap as well. Then get some
dielectric grease from an automotive store (look in the spark plug section)
and smear a coat of it on the bottom of the suction cup and reassemble,
should be good as new.


And don`t stick your finger in the hole in the glass tube! even after
you discharged it

Ron

Nor your tongue (he said, tongue in cheek). :-)

Tom

Ahh well, unless he is Homer Simpson he will only do it once!

David

Tom MacIntyre wrote:

On Sun, 1 May 2005 11:02:19 +0000 (UTC), "Ron(UK)"
wrote:


And don`t stick your finger in the hole in the glass tube! even after
you discharged it

Ron

Nor your tongue (he said, tongue in cheek). :-)

Tom

"quietguy" wrote in
message
...

Ahh well, unless he is Homer Simpson he will only do it once!

My favorite episode of the "Beverly Hillbillies" - where Jethro tried to
X-Ray the bear!
--
N