Sony KV-35S26 - Tube finally shot?

[[email protected]]

Hi Guys:

About 2 years, a customer brought in his Sony KV-35S26 TV. The heater
was shorted so I isolated it, and feed it from a separate winding that
I
put around the flyback.

Well, it came back in yesterday with a "no picture" problem. Sound is
great, and HV is present. I could see sparkles of blue on the screen
and decided to measure the red, green and blue cathode voltages.

Blue was fine (ranging from about 90 to 120VDC), green would sometimes
be about 100V but then shot up to over 200V. The red cathode stayed
at over 200V. I removed the reg and green connections from the neck
board
and now have a beautiful blue picture.....great for Barney
enthousiasts

Anybody have any ideas, other than the landfill?

Thanks,

Tedd, VE3TJD

 

[Art]

Cost of the CRT preludes repair.

 

[Jeroni Paul]

[email protected] expuso:

Hi Guys:

About 2 years, a customer brought in his Sony KV-35S26 TV. The heater
was shorted so I isolated it, and feed it from a separate winding that
I
put around the flyback.

Well, it came back in yesterday with a "no picture" problem. Sound is
great, and HV is present. I could see sparkles of blue on the screen
and decided to measure the red, green and blue cathode voltages.

Blue was fine (ranging from about 90 to 120VDC), green would sometimes
be about 100V but then shot up to over 200V. The red cathode stayed
at over 200V. I removed the reg and green connections from the neck
board
and now have a beautiful blue picture.....great for Barney
enthousiasts

Anybody have any ideas, other than the landfill?

Thanks,

Tedd, VE3TJD

You've quite high voltages on cathodes, it is normal the screen is blank.
You should look at the reason, it seems like the set is blanking the picture
for some reason.
Being a Sony it is maybe because the automatic balance system never senses
enough probe current through the cathodes to start a picture, it thinks the
cathodes are still not warm enough. To check this condition, try to increase
G2, that will help a tired tube live some time more. To test the tube you
might short a cathode to ground with the set off, and then power it, if the
picture starts showing a strong color then the tube is fine, don't let it
warm with that short!! just one second to see.