Great Mystery Magnavox TV 27MS3404/17 Problem

[Brad]

Hi,

I have a Magnavox TV model 27MS3404/17, chassis L01.1UAC-7638
(mfg. 06/05) in my service shop that comes on, picture shows for a few
seconds, then the TV goes "off". Actually the horizontal sweep shuts
down. The SMPS is still "running" at "full power" (Reg B+ is 130V).
Note: The HV was around 27KV with picture showing.

If I use a pattern generator (color bars, cross hatch, etc.), the TV stays
on!!!!! However, with a normal TV signal, it goes off in a few seconds
after the picture shows. With no signal (snow), the TV stays on much longer
but it still goes off. It only stays on with the pattern generator!!!!

Note: I had tried different "Screen" (on FBT) settings.

Any idea what is the cause of this weird problem?

Thanks in advance, Brad

Before you type your password, credit card number, etc.,
be sure there is no active keystroke logger (spyware) in your PC.

 

[Charles Schuler]

Hi,

I have a Magnavox TV model 27MS3404/17, chassis L01.1UAC-7638
(mfg. 06/05) in my service shop that comes on, picture shows for a few
seconds, then the TV goes "off". Actually the horizontal sweep shuts
down. The SMPS is still "running" at "full power" (Reg B+ is 130V).
Note: The HV was around 27KV with picture showing.

If I use a pattern generator (color bars, cross hatch, etc.), the TV
stays
on!!!!! However, with a normal TV signal, it goes off in a few seconds
after the picture shows. With no signal (snow), the TV stays on much
longer
but it still goes off. It only stays on with the pattern generator!!!!

Note: I had tried different "Screen" (on FBT) settings.

Any idea what is the cause of this weird problem?

Is the beam current less with the pattern generator signal? Might be a clue
there.

 

[Kevin S.]

Hi,

I have a Magnavox TV model 27MS3404/17, chassis L01.1UAC-7638
(mfg. 06/05) in my service shop that comes on, picture shows for a few
seconds, then the TV goes "off". Actually the horizontal sweep shuts
down. The SMPS is still "running" at "full power" (Reg B+ is 130V).
Note: The HV was around 27KV with picture showing.

If I use a pattern generator (color bars, cross hatch, etc.), the TV stays
on!!!!! However, with a normal TV signal, it goes off in a few seconds
after the picture shows. With no signal (snow), the TV stays on much longer
but it still goes off. It only stays on with the pattern generator!!!!

Note: I had tried different "Screen" (on FBT) settings.

Any idea what is the cause of this weird problem?

Thanks in advance, Brad

Just did one of these... it's a little 25v 47ufd cap a couple of inches
away from your HOT. I don't remember the position, but it's the only
little cap right off the HOT (a couple of inches.) Change it out and
you're probably good.
Good luck.

Kevin S.