PTK195 P56830 is now up and running! Suggestion on checking the male
plug service port is right except evidence is there, very clean
because of the board wash so I simply removed dry bits & swabbed with
acetone. This helped me to decide to re-init the corrupted eeprom and
got vertical operation running and finish adjusting.

Now on Pioneer SD-P55A3-K well, We had this unit 2 years ago and had
to replace the deflection/power board. Unit here now and so went
ahead and recapped this board (mostly 220uF, 1uF, three 47uF and
couple more around one regulator IC). Got proj going. Now still
shutting down after 10-15 minutes, you can press power button and get
picture back again right away.

Googled showed that pioneer says change this board and HV splitter
module as a set. At this point I can't see a reason for this since
proj was here for dried up capacitors. The solder joints are not the
problem as we already took care of this 2 years ago.

I'm considering getting the convergence amp board out and take a look
at solder joints.

By the way, I have another Pioneer with same dried up caps and don't
want to go through this repeat 10-15 minute then shut down part.

Suggestions?

Cheers, Wizard

Put a video camera on it and look for an arc as it shuts down. Had one with
an arcing CRT last year that made me nuts.

Also, did you resolder the several hundred ring cracks on the board that you
got from Pioneer? Most boards from them need it even though they are
"rebuilt."

Leonard

"Jason D." wrote in message
...
PTK195 P56830 is now up and running! Suggestion on checking the male
plug service port is right except evidence is there, very clean
because of the board wash so I simply removed dry bits & swabbed with
acetone. This helped me to decide to re-init the corrupted eeprom and
got vertical operation running and finish adjusting.

Now on Pioneer SD-P55A3-K well, We had this unit 2 years ago and had
to replace the deflection/power board. Unit here now and so went
ahead and recapped this board (mostly 220uF, 1uF, three 47uF and
couple more around one regulator IC). Got proj going. Now still
shutting down after 10-15 minutes, you can press power button and get
picture back again right away.

Googled showed that pioneer says change this board and HV splitter
module as a set. At this point I can't see a reason for this since
proj was here for dried up capacitors. The solder joints are not the
problem as we already took care of this 2 years ago.

I'm considering getting the convergence amp board out and take a look
at solder joints.

By the way, I have another Pioneer with same dried up caps and don't
want to go through this repeat 10-15 minute then shut down part.

Suggestions?

Cheers, Wizard

On Tue, 16 May 2006 17:21:35 -0400, "Leonard Caillouet"
wrote:

Put a video camera on it and look for an arc as it shuts down. Had one with
an arcing CRT last year that made me nuts.

Also, did you resolder the several hundred ring cracks on the board that you
got from Pioneer? Most boards from them need it even though they are
"rebuilt."

Leonard

Yes, 1001 shiny solder joints on that deflection board. COMPLETELY!


Didn't stop the shut down after 10-15 minutes. There is no "click" or
"snap" that goes with it. I can turn it back on right now without
having to unplug to reset x-ray protection when shut down occurs.

Cheers, Wizard

"Jason D." wrote in message
...
On Tue, 16 May 2006 17:21:35 -0400, "Leonard Caillouet"
wrote:

Put a video camera on it and look for an arc as it shuts down. Had one
with
an arcing CRT last year that made me nuts.

Also, did you resolder the several hundred ring cracks on the board that
you
got from Pioneer? Most boards from them need it even though they are
"rebuilt."

Leonard

Yes, 1001 shiny solder joints on that deflection board. COMPLETELY!


Didn't stop the shut down after 10-15 minutes. There is no "click" or
"snap" that goes with it. I can turn it back on right now without
having to unplug to reset x-ray protection when shut down occurs.

Cheers, Wizard

Re the SD-P55A3

Are you turning it back on with the large power button or the remote? The
big power button on the front disconnects the mains, using it is just like
unplugging the set.

There are shutdown LED's inside this set to monitor the powerdown circuit.
When the set shuts down, look on the deflection board for a lit LED near the
relays. This is the main powerdown monitor, and if it is lit the set is
going into shutdown. If you can confirm it is actually going into shutdown
then we can look for what circuit is tripping it

There are some other LED's for the PD circuit that will light very
briefly when the set trips shutdown. You will need to be looking at them
with the light off in the room so you can see. If any of the LED's light
even a little bit you can narrow your search down. These sets had LOTS of
problems with the amp assembly and digital convergence DAC board. They had a
fault that would cause excessive inrush current on the +/-25V lines and make
the set shutdown.

On the amp assembly find the shutdown LED and watch it very close. I'll
almost bet the problem is there. Another thing that may help is having an
assistant power the set on, and look at the fuses for the + and -25v lines
that run the convergence IC's these fuses are on the deflection board behind
a small transformer. Easiest way to see them is to slide the board rack back
and tilt it towards you. Many times I've seen a problem on the amp assembly
draw enough inrush current to heat the fuse red without blowing. Stress over
time eventually causes fuse failure, and be sure to check the fuses and make
sure they are the correct size, I have seen techs put a larger rated/slow
blow type fuses in these sets and think they fixed it, which is not proper
at all, but it happens.

Jammy

Forgot to note in my other response if the set is not going into shutdown,
check the power_on output from the micro and see if the set is just shutting
itself off. Bad microprocessors on these sets are uncommon, but not unheard
of. You might try heating the micro with a hair dryer to see if the set
shuts down sooner.

Jammy

On Wed, 17 May 2006 09:26:05 -0500, "ampdoc"
wrote:


On the amp assembly find the shutdown LED and watch it very close. I'll
almost bet the problem is there. Another thing that may help is having an
assistant power the set on, and look at the fuses for the + and -25v lines
that run the convergence IC's these fuses are on the deflection board behind
a small transformer. Easiest way to see them is to slide the board rack back
and tilt it towards you. Many times I've seen a problem on the amp assembly
draw enough inrush current to heat the fuse red without blowing. Stress over
time eventually causes fuse failure, and be sure to check the fuses and make
sure they are the correct size, I have seen techs put a larger rated/slow
blow type fuses in these sets and think they fixed it, which is not proper
at all, but it happens.

Jammy



SD-P55A3-K Shuts down 10-15 minutes later. I have service manual
(real thing) for it no trouble shooting section.

Thanks, this time I paid attention to that red LED in PSU area. And
this time I heard "Whu-THUMP" of speakers when TV shuts down and red
LED lit. You're right this time, I wasn't thinking, that big power
button is "hard power button".

The soft power button didn't get tv back, the hard power button did.

The convergence amp board with smaller green daughterboard is
currently on the bench going through resolder job. This did not react
to hitting with beat up plastic stick (old 5" front cover from 5 disc
player). There is no LED for this model, this is very old type, 1992.

Remember caps I listed is all what I changed out in power/deflection
board; four 220uf, three 47uf, one 1uF, one 100uF and couple caps for
the regulator IC (typical 78xx). These caps flunked the ESR meter
check.

Interesting thing to say about that vertical circuit, no electrolytic
cap for pump charge. That's something to say!

Hope that can keep suggestions coming.

Cheers, Wizard

The soft power button didn't get tv back, the hard power button did.

The convergence amp board with smaller green daughterboard is
currently on the bench going through resolder job. This did not react
to hitting with beat up plastic stick (old 5" front cover from 5 disc
player). There is no LED for this model, this is very old type, 1992.



There should be an LED on the amp assembly, near the bracket for the DAC
board and close to where the ribbon connector from the DAC connects to the
amp assembly. It is very small and hard to see, and does not have a latch
circuit like the main PD led does. If it's indicating it will barely flash
briefly at the moment of shutdown. Should be on the rear of the board as it
sits in the set. I'm sure all of the 50/55A3 and A5 sets had an LED there.
Important to note that NONE of the LED's have a latch other than the main PD
one. The others will barely light then go off on shutdown, you probably
won't notice it unless the room is very dark. Were the fuses correct? 4a
fast blow, I believe, on the deflection board +/-25V supply lines.

Jammy

Well,

Today was the up and close personal with the convergence amp board,
replaced all 10 220uF, 4 100uF, couple 330uF (6.3V). Tentatively
fixed since TV is still up for 45 minutes before I had to leave early
for bus for the day. Reason for this particular day was my nice
boss's 1992 3.0 MPV is in shop for rack replacement. I get a short
ride to bus stop daily so I don't have to change so many buses on that
particular evening, I had to do 4 bus changes.

This TV was working for years till caps dried up enough to stay
shutdown for good. That particular problem would had been done years
ago since Pioneers told shops to replace this convergence stuff if one
comes in for this reason LOOONG ago. This one was in service for long
time already and had problems unrelated to this second problem that
showed up after rebuilding the power/deflection board.

Oh, there is no LED in the location for the convergence stuff. BUT
there is LED *under* the DAC daughterboard and this is for vertical
circuit trip. This boggles me to hide this one. :-O

By the way, I have newer Pioneer that's is now ours, needs caps so
I'll know what to do with that one. Whoo hoo.

With closing comment, be prepared to spend time with these, give 2-3
hours minimum and at least 30 caps on both deflection/power and
convergence boards. Quicker to ESR them in one pass and use permanent
mark those duff ones. Solder, solder throughly!

All 10 220uF 35V reads appox "22" on bob parker's ESR meter and couple
100uF for the input side of +/- 5V regulators reads "1", others were
due for swapping so this got done.

Stay tuned!

Cheers, Wizard

"Jason D." wrote in message
...
Well,

Today was the up and close personal with the convergence amp board,
replaced all 10 220uF, 4 100uF, couple 330uF (6.3V). Tentatively
fixed since TV is still up for 45 minutes before I had to leave early
for bus for the day. Reason for this particular day was my nice
boss's 1992 3.0 MPV is in shop for rack replacement. I get a short
ride to bus stop daily so I don't have to change so many buses on that
particular evening, I had to do 4 bus changes.

This TV was working for years till caps dried up enough to stay
shutdown for good. That particular problem would had been done years
ago since Pioneers told shops to replace this convergence stuff if one
comes in for this reason LOOONG ago. This one was in service for long
time already and had problems unrelated to this second problem that
showed up after rebuilding the power/deflection board.

Oh, there is no LED in the location for the convergence stuff. BUT
there is LED *under* the DAC daughterboard and this is for vertical
circuit trip. This boggles me to hide this one. :-O

By the way, I have newer Pioneer that's is now ours, needs caps so
I'll know what to do with that one. Whoo hoo.

With closing comment, be prepared to spend time with these, give 2-3
hours minimum and at least 30 caps on both deflection/power and
convergence boards. Quicker to ESR them in one pass and use permanent
mark those duff ones. Solder, solder throughly!

All 10 220uF 35V reads appox "22" on bob parker's ESR meter and couple
100uF for the input side of +/- 5V regulators reads "1", others were
due for swapping so this got done.

Stay tuned!

Cheers, Wizard

Lol I knew there was an LED on the thing somewhere.

Hope it works out for you

Jammy

On Sat, 20 May 2006 00:34:41 -0500, "ampdoc"
wrote:


"Jason D." wrote in message
.. .
Well,

Lol I knew there was an LED on the thing somewhere.

Hope it works out for you

Jammy


Ok, definely fixed, passed 4 hours now and ready for owner to pick up.


Cheers, Wizard