RCA TV model 27V412T, chassis M134C turns off, then on by itself

[Brad]

Hi,

I have a RCA TV model 27V412T, chassis M134C (mfg 01/06) in my shop
that seems to have a mind of it's own. My customer said this problem got
worse over time (a few weeks). I have Sams Photofact 5234.

The TV will play for a short time, then turn off, a short time later, it
turns back on, then again it goes off, etc. I checked all solder joints
(AOK).

HV is 28KV, reg B+ is 130V "run", and 10V in standby.. While the TV
played, flexing the circuit board (removed from it's holder), tapping the
circuit board, using a hot air gun on parts, had no effect.

I checked electroylitics in primary side of SMPS and reg. B+ (AOK).
I checked voltages on secondary side of SMPS and found a schematic
error for 24V source. I found 24V present at emitter of Q205 used as a
"switch" (one of several) which indicates the 24V source is normal.

Did anyone encounter a similar problem?

Thanks in advance, Brad

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[Dani]

Possibly bad tact switches. Unhook the FPA pcb plug, if this unit has
one. Dani.