Akai PT4298HDX convergence board

Hi.
I have an Akai PT4298HDX projection TV which about two years ago
manifested the infamous convergence board issue. I had it repaired
professionally back then, but when last week the problem recurred, I
decided I'd try to repair it myself - or not at all. I bought a couple
of STKs (found them online for $10.99 a piece) and installed them on the
board, but one of them is probably bad -- the RZ144 and RZ145 resistors
keep blowing. I also had to replace the 3.5 A pico fuse on the Blue
circuit, which hasn't blown yet. I'm thinking of replacing the whole
board, rather than going through the tedious task of re-soldering an STK
again.
My PCB has the number P55A AA41-00601B, but I couldn't find a reference
for it online. I can see posts about replacing it with a Samsung part
#BP95-00142E, which is available from at least two online retailers for
about $75. Can anyone here confirm that they've installed that board on
an Akai PT4298HDX and it works?
Thanks.
Svilen

Samsung makes the Akai. Check with Andrews Electronics for cross match with
the part #s.
"Svilen Stoicheff" wrote in message
. ..
Hi.
I have an Akai PT4298HDX projection TV which about two years ago
manifested the infamous convergence board issue. I had it repaired
professionally back then, but when last week the problem recurred, I
decided I'd try to repair it myself - or not at all. I bought a couple of
STKs (found them online for $10.99 a piece) and installed them on the
board, but one of them is probably bad -- the RZ144 and RZ145 resistors
keep blowing. I also had to replace the 3.5 A pico fuse on the Blue
circuit, which hasn't blown yet. I'm thinking of replacing the whole
board, rather than going through the tedious task of re-soldering an STK
again.
My PCB has the number P55A AA41-00601B, but I couldn't find a reference
for it online. I can see posts about replacing it with a Samsung part
#BP95-00142E, which is available from at least two online retailers for
about $75. Can anyone here confirm that they've installed that board on an
Akai PT4298HDX and it works?
Thanks.
Svilen

Svilen Stoicheff wrote:
Hi.
I have an Akai PT4298HDX projection TV which about two years ago
manifested the infamous convergence board issue. I had it repaired
professionally back then, but when last week the problem recurred, I
decided I'd try to repair it myself - or not at all. I bought a couple
of STKs (found them online for $10.99 a piece) and installed them on the
board, but one of them is probably bad -- the RZ144 and RZ145 resistors
keep blowing. I also had to replace the 3.5 A pico fuse on the Blue
circuit, which hasn't blown yet. I'm thinking of replacing the whole
board, rather than going through the tedious task of re-soldering an STK
again.
My PCB has the number P55A AA41-00601B, but I couldn't find a reference
for it online. I can see posts about replacing it with a Samsung part
#BP95-00142E, which is available from at least two online retailers for
about $75. Can anyone here confirm that they've installed that board on
an Akai PT4298HDX and it works?
Thanks.
Svilen

I ordered a new convergence board, # BP94-00155A. When I installed it,
the blue convergence in the bottom left part of the screen looked very
distorted, while elsewhere it was fine. I thought the board I got was
defective, so I returned it and got another one, but the result was the
same. See these pictures:
http://www.stoicheff.com/stuff/TV/1.jpg
http://www.stoicheff.com/stuff/TV/2.jpg
http://www.stoicheff.com/stuff/TV/3.jpg
http://www.stoicheff.com/stuff/TV/4.jpg

It seems impossible to correct the blue convergence with just the remote
control. Are there any other adjustments that I can try, or should I be
looking elsewhere, not just at the convergence board?
Any tips will be appreciated. I know the "find a good Samsung shop
answer" so you can spare me that one ;-)

Thanks.
Svilen

On Oct 10, 6:14 pm, Svilen Stoicheff wrote:
Svilen Stoicheff wrote:
Hi.
I have an Akai PT4298HDX projection TV which about two years ago
manifested the infamous convergence board issue. I had it repaired
professionally back then, but when last week the problem recurred, I
decided I'd try to repair it myself - or not at all. I bought a couple
of STKs (found them online for $10.99 a piece) and installed them on the
board, but one of them is probably bad -- the RZ144 and RZ145 resistors
keep blowing. I also had to replace the 3.5 A pico fuse on the Blue
circuit, which hasn't blown yet. I'm thinking of replacing the whole
board, rather than going through the tedious task of re-soldering an STK
again.
My PCB has the number P55A AA41-00601B, but I couldn't find a reference
for it online. I can see posts about replacing it with a Samsung part
#BP95-00142E, which is available from at least two online retailers for
about $75. Can anyone here confirm that they've installed that board on
an Akai PT4298HDX and it works?
Thanks.
Svilen

I ordered a new convergence board, # BP94-00155A. When I installed it,
the blue convergence in the bottom left part of the screen looked very
distorted, while elsewhere it was fine. I thought the board I got was
defective, so I returned it and got another one, but the result was the
same. See these pictures:http://www.stoicheff.com/stuff/TV/1....stuff/TV/4.jpg

It seems impossible to correct the blue convergence with just the remote
control. Are there any other adjustments that I can try, or should I be
looking elsewhere, not just at the convergence board?
Any tips will be appreciated. I know the "find a good Samsung shop
answer" so you can spare me that one ;-)

Thanks.
Svilen

Are the convergence adjustments for blue all in the center of their
ranges or is it getting some wacky settings from the old board? Is
there a "first birthday" or "restore factory defaults" ? If the
convergence drives are all neutral you'd have to go to the rest of the
blue deflection circuitry. It could be bad caps but that looks more
like a damaged inductor whether the yoke of other coils in the
deflection system.

Sorry I can't be more help as I don't work on RPTV, just a few direct
view CRT monitors in between Betacam SP and Ampex 1" and 2" VTRs.

GG

G-squared wrote:
On Oct 10, 6:14 pm, Svilen Stoicheff wrote:
Svilen Stoicheff wrote:
Hi.
I have an Akai PT4298HDX projection TV which about two years ago
manifested the infamous convergence board issue. I had it repaired
professionally back then, but when last week the problem recurred, I
decided I'd try to repair it myself - or not at all. I bought a couple
of STKs (found them online for $10.99 a piece) and installed them on the
board, but one of them is probably bad -- the RZ144 and RZ145 resistors
keep blowing. I also had to replace the 3.5 A pico fuse on the Blue
circuit, which hasn't blown yet. I'm thinking of replacing the whole
board, rather than going through the tedious task of re-soldering an STK
again.
My PCB has the number P55A AA41-00601B, but I couldn't find a reference
for it online. I can see posts about replacing it with a Samsung part
#BP95-00142E, which is available from at least two online retailers for
about $75. Can anyone here confirm that they've installed that board on
an Akai PT4298HDX and it works?
Thanks.
Svilen
I ordered a new convergence board, # BP94-00155A. When I installed it,
the blue convergence in the bottom left part of the screen looked very
distorted, while elsewhere it was fine. I thought the board I got was
defective, so I returned it and got another one, but the result was the
same. See these pictures:http://www.stoicheff.com/stuff/TV/1....stuff/TV/4.jpg

It seems impossible to correct the blue convergence with just the remote
control. Are there any other adjustments that I can try, or should I be
looking elsewhere, not just at the convergence board?
Any tips will be appreciated. I know the "find a good Samsung shop
answer" so you can spare me that one ;-)

Thanks.
Svilen

Are the convergence adjustments for blue all in the center of their
ranges or is it getting some wacky settings from the old board? Is
there a "first birthday" or "restore factory defaults" ?

That's what I'm trying to find out. If there's a way to go back to
factory defaults, I don't know of it.

On Oct 11, 6:56 pm, Svilen Stoicheff wrote:
G-squared wrote:
Are the convergence adjustments for blue all in the center of
their
ranges or is it getting some wacky settings from the old board?
Is
there a "first birthday" or "restore factory defaults" ?

That's what I'm trying to find out. If there's a way to go back to
factory defaults, I don't know of it.

It's time to get the service manual. You might have some luck trolling
on line for at least a portion of the manual.

When I bought the manuals for our Samsung, it was $15 on a CD-ROM as
a .PDF file. Actually more convenient (and cheaper) than a printed
manual as the comouter can 'read' the text for you.

GG

G-squared wrote:
On Oct 11, 6:56 pm, Svilen Stoicheff wrote:
G-squared wrote:
Are the convergence adjustments for blue all in the center of
their
ranges or is it getting some wacky settings from the old board?
Is
there a "first birthday" or "restore factory defaults" ?

That's what I'm trying to find out. If there's a way to go back to
factory defaults, I don't know of it.

It's time to get the service manual. You might have some luck trolling
on line for at least a portion of the manual.

And so I did -- I found the portion of the Samsung manual that deals
with alignment and convergence adjustments in full service mode. For the
benefit of others, I've uploaded it he
http://www.stoicheff.com/stuff/TV/sbsc.pdf
I was able to do a decent job last night. Thanks for pointing me in the
right direction.


When I bought the manuals for our Samsung, it was $15 on a CD-ROM as
a .PDF file. Actually more convenient (and cheaper) than a printed
manual as the comouter can 'read' the text for you.

GG

G-squared wrote:
On Oct 11, 6:56 pm, Svilen Stoicheff wrote:
G-squared wrote:
Are the convergence adjustments for blue all in the center of
their
ranges or is it getting some wacky settings from the old board?
Is
there a "first birthday" or "restore factory defaults" ?

That's what I'm trying to find out. If there's a way to go back to
factory defaults, I don't know of it.

It's time to get the service manual. You might have some luck trolling
on line for at least a portion of the manual.

When I bought the manuals for our Samsung, it was $15 on a CD-ROM as
a .PDF file. Actually more convenient (and cheaper) than a printed
manual as the comouter can 'read' the text for you.

GG

Try Mute 1 8 3 while set is on, then make sure to save the settings whan you
are happy. Service Literature would be a very wise investment, if you can
get it.
"Svilen Stoicheff" wrote in message
. ..
G-squared wrote:
On Oct 11, 6:56 pm, Svilen Stoicheff wrote:
G-squared wrote:
Are the convergence adjustments for blue all in the center of
their
ranges or is it getting some wacky settings from the old board?
Is
there a "first birthday" or "restore factory defaults" ?

That's what I'm trying to find out. If there's a way to go back to
factory defaults, I don't know of it.

It's time to get the service manual. You might have some luck trolling
on line for at least a portion of the manual.

When I bought the manuals for our Samsung, it was $15 on a CD-ROM as
a .PDF file. Actually more convenient (and cheaper) than a printed
manual as the comouter can 'read' the text for you.

GG