Maker Pro
Maker Pro

Philips 27B800 TV powers on for 1 sec

D

DaveC

Jan 1, 1970
0
Then it shuts off immediately. No picture, no sound.

Is this typical symptom of this model? Probable cause(s)?

Thanks,
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
[email protected]
This is an invalid return address
Please reply in the news group
 
B

Bill S

Jan 1, 1970
0
Then it shuts off immediately. No picture, no sound.

Is this typical symptom of this model? Probable cause(s)?

Power supply runs all the time, so it is pretty easy to
test. Shutdown will occur if it doesn't detect scan
within a certain time limit, so check horiz and vert
circuits. Most common failure is 100uF 35V flyback
capacitor near vertical IC, which causes the vertical
IC to overheat and short out, which sometimes burns up
one or both of the fusible resistors and/or shorts one
or both of the vertical supply diodes.

C557, IC500, R445, R420, D445, D409
 
D

DaveC

Jan 1, 1970
0
Power supply runs all the time, so it is pretty easy to
test. Shutdown will occur if it doesn't detect scan
within a certain time limit, so check horiz and vert
circuits. Most common failure is 100uF 35V flyback
capacitor near vertical IC, which causes the vertical
IC to overheat and short out, which sometimes burns up
one or both of the fusible resistors and/or shorts one
or both of the vertical supply diodes.

C557, IC500, R445, R420, D445, D409

Getting HV, briefly, during 1-second power-on. Don't know voltage; it just
lights a neon bulb near the flyback.

IC500 has no obvious signs of catastrophe, nor does C557 show bulging or
other signs of failure. The R's don't look burnt at all. No obvious visible
signs of failure anywhere.

Where and what is the reference voltage I should see? I see the adjustment on
the primary side of the SMPS, but not sure what to look for and adjust to.
Measured 163vdc at the 680u/200v cap (forget the desig.).

Other checks?

This set *wants* to turn on : -)

Thanks,
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
[email protected]
This is an invalid return address
Please reply in the news group
 
D

DaveC

Jan 1, 1970
0
Getting HV, briefly, during 1-second power-on. Don't know voltage; it just
lights a neon bulb near the flyback.

....lights a neon bulb *I* place near the flyback, that is.
--
Please, no "Go Google this" replies. I wouldn't
ask a question here if I hadn't done that already.

DaveC
[email protected]
This is an invalid return address
Please reply in the news group
 
Top