Hi Charles,

I thought the beam current might be causing a shut down. I have Sams
Photofact 4968 for this model TV, but it leaves out a lot of information.
No pin out info on the jungle IC 7200, TDA9588H/N1/1133, and I couldn't
find it on the web. I assumed pin 54 may control shut down by excessive
beam current so I opened that circuit and used a 100K, then 200K to ground
resistor which set the voltage close to what was on the schematic, but the
TV still shuts down. Another pin 55 on that IC relates to "BCI", but I
didn't experiment with that circuit. I have used a lot of time trying to
fix this mystery problem.

Brad


On Tue, 9 Jan 2007 17:17:42 -0500, "Charles Schuler"
wrote:


"Brad" wrote in message
...
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.