Samsung plasma TV PS-42V4S

P

powerampfreak

Guest
Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF
 
On 19 Feb, 10:30, powerampfreak <powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF
Click to expand...
Need to describe the problem better: There are a lot of vertical lines
on the screen not lit at all. I would say 1st, 5th and 10th.. and it
all repeats again.
So most of the picture is there but is loosing some lines in every
inch of the screen from left ro right.
 
powerampfreak <powerampfreak@hotmail.com> wrote in message
news:f46cbc75-bb0c-44b2-b49d-e56fae83d5f8@v20g2000yqv.googlegroups.com...
On 19 Feb, 10:30, powerampfreak <powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF

Need to describe the problem better: There are a lot of vertical lines
on the screen not lit at all. I would say 1st, 5th and 10th.. and it
all repeats again.
So most of the picture is there but is loosing some lines in every
inch of the screen from left ro right.
Click to expand...

Are you saying there must be no problem with the final demultiplexing
chippery at the screen as the Menu/OSD display comes up fine?
 
powerampfreak <powerampfreak@hotmail.com> wrote in message
news:978ad71c-8228-40a0-9df7-cd22c7b7902b@l26g2000yqd.googlegroups.com...
On 19 Feb, 11:41, "N_Cook" <dive...@tcp.co.uk> wrote:
powerampfreak <powerampfr...@hotmail.com> wrote in message


news:f46cbc75-bb0c-44b2-b49d-e56fae83d5f8@v20g2000yqv.googlegroups.com...



On 19 Feb, 10:30, powerampfreak <powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think
of
verticle lines through the entire screen, I would say the 1st, 5th
and
10th is not lit. BUT, menus and on-screen displays work perfect
giving
a correct picture. But which ever input source I choose, (both
scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF

Need to describe the problem better: There are a lot of vertical lines
on the screen not lit at all. I would say 1st, 5th and 10th.. and it
all repeats again.
So most of the picture is there but is loosing some lines in every
inch of the screen from left ro right.

Are you saying there must be no problem with the final demultiplexing
chippery at the screen as the Menu/OSD display comes up fine?

In my world, thinking in terms of old CRT screens which recieve R,G,B
signals to drive the tube, the menu OSD information is mixed together
with the CVBS signal and fed the the RGB amps.
If there was a faulty tube, giving for instance, no red colour, both
picture and osd information was affected.
In this plasma case, all "dark" lines starts to light when displaying
osd information.
That makes me believe the plasma screen itself and it's drive
electronics is ok. I know very little about plasma technology, was
mostly involved with crt tv repairs back then.
Is my thinking incorrect?
I would love if there were some faulty power electronics failure,
instead of scaler/picture processing dsp failure.
But of course I don't know yet.
Appreciate any advice to move on. Thanks a lot!

Regards
PAF
Click to expand...
I would suspect a lifted contact on a SMD lead somewhere back in the initial
video processing
 
On 19 Feb, 11:41, "N_Cook" <dive...@tcp.co.uk> wrote:
powerampfreak <powerampfr...@hotmail.com> wrote in message

news:f46cbc75-bb0c-44b2-b49d-e56fae83d5f8@v20g2000yqv.googlegroups.com...



On 19 Feb, 10:30, powerampfreak <powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF

Need to describe the problem better: There are a lot of vertical lines
on the screen not lit at all. I would say 1st, 5th and 10th.. and it
all repeats again.
So most of the picture is there but is loosing some lines in every
inch of the screen from left ro right.

Are you saying there must be no problem with the final demultiplexing
chippery at the screen as the Menu/OSD display comes up fine?
Click to expand...
In my world, thinking in terms of old CRT screens which recieve R,G,B
signals to drive the tube, the menu OSD information is mixed together
with the CVBS signal and fed the the RGB amps.
If there was a faulty tube, giving for instance, no red colour, both
picture and osd information was affected.
In this plasma case, all "dark" lines starts to light when displaying
osd information.
That makes me believe the plasma screen itself and it's drive
electronics is ok. I know very little about plasma technology, was
mostly involved with crt tv repairs back then.
Is my thinking incorrect?
I would love if there were some faulty power electronics failure,
instead of scaler/picture processing dsp failure.
But of course I don't know yet.
Appreciate any advice to move on. Thanks a lot!

Regards
PAF
 
On 19 Feb, 16:55, "N_Cook" <dive...@tcp.co.uk> wrote:
powerampfreak <powerampfr...@hotmail.com> wrote in message

news:978ad71c-8228-40a0-9df7-cd22c7b7902b@l26g2000yqd.googlegroups.com...> On 19 Feb, 11:41, "N_Cook" <dive...@tcp.co.uk> wrote:
powerampfreak <powerampfr...@hotmail.com> wrote in message

news:f46cbc75-bb0c-44b2-b49d-e56fae83d5f8@v20g2000yqv.googlegroups.com...





On 19 Feb, 10:30, powerampfreak <powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think
of
verticle lines through the entire screen, I would say the 1st, 5th
and
10th is not lit. BUT, menus and on-screen displays work perfect
giving
a correct picture. But which ever input source I choose, (both
scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF

Need to describe the problem better: There are a lot of vertical lines
on the screen not lit at all. I would say 1st, 5th and 10th.. and it
all repeats again.
So most of the picture is there but is loosing some lines in every
inch of the screen from left ro right.

Are you saying there must be no problem with the final demultiplexing
chippery at the screen as the Menu/OSD display comes up fine?

In my world, thinking in terms of old CRT screens which recieve R,G,B
signals to drive the tube, the menu OSD information is mixed together
with the CVBS signal and fed the the RGB amps.
If there was a faulty tube, giving for instance, no red colour, both
picture and osd information was affected.
In this plasma case, all "dark" lines starts to light when displaying
osd information.
That makes me believe the plasma screen itself and it's drive
electronics is ok. I know very little about plasma technology, was
mostly involved with crt tv repairs back then.
Is my thinking incorrect?
I would love if there were some faulty power electronics failure,
instead of scaler/picture processing dsp failure.
But of course I don't know yet.
Appreciate any advice to move on. Thanks a lot!

Regards
PAF

I would suspect a lifted contact on a SMD lead somewhere back in the initial
video processing
Click to expand...
This is exactly the hints I need. Could you possibly explain it a bit
further?
May I contact you directly by mail?

Regards
PAF
 
On Fri, 19 Feb 2010 01:30:03 -0800 (PST), powerampfreak
<powerampfreak@hotmail.com> wrote:

Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF
Can you read schematics? The service manual for that set appears to
Click to expand...
be available here: http://www.nodevice.com/manual/Samsung/page54.html

This definitely sounds like a scalar problem; not a driver or panel
issue. Many manufacturers use Samsung panels and drive electronics in
their plasma sets. The actual video processing is handled on a single
card designed and manufactured by the company whose name will appear
on the finished product. I would not be optomistic of this being
repairable at the component level. The video processing card consists
of a number of fairly complex processors working together.

PlainBill
 
powerampfreak <powerampfreak@hotmail.com> wrote in message
news:b6045eee-7954-4241-8e60-4b67bb278956@g26g2000yqn.googlegroups.com...
On 19 Feb, 20:55, PlainBil...@yahoo.com wrote:
On Fri, 19 Feb 2010 01:30:03 -0800 (PST), powerampfreak

powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF

Can you read schematics? The service manual for that set appears to
be available here:http://www.nodevice.com/manual/Samsung/page54.html

This definitely sounds like a scalar problem; not a driver or panel
issue. Many manufacturers use Samsung panels and drive electronics in
their plasma sets. The actual video processing is handled on a single
card designed and manufactured by the company whose name will appear
on the finished product. I would not be optomistic of this being
repairable at the component level. The video processing card consists
of a number of fairly complex processors working together.

PlainBill
Click to expand...
I'm familiar with schematics, I'm working my electronics, but not
plasma TV's unfortunately..
I did buy the service manual for the TV, at nodevice.com. Thanks for
the link!
Unfortunately, the service manual wasn't complete, the smps part and
output driver parts were missing,
but it seems most of the video processing board is there.
I suspect one of those processors to be the problem:
ASI501 which isn't possible to desolder (legs are underneath)
GENESIS FL12310 (possible to desolder)
I guess one of these ic's is the scaler.

In case, anyone has a complete board for no use, I'm interested (not
too optimistic...)

Board: NELSON
Code: BN41-00452 C
Rev: MP 1.4 (2004-08-19)

When having no input source connected, the screen is ALL blue. (all
lines OK)
Pressing MENU, it all looks briliant.
Connecting a video source, the picture has the "vertical lines"
problem. (still menu and all OSD is ok)
Also, I noticed, when having no input source connected (blue screen)
and apply input source, then screen goes all black for one second,
before it displays the video. During this second, when screen is
black, it's possible to see the veritcal lines problem very faint in
the black screen aswell.

As Plainbill said, I'm also starting to loose my optimism in getting
this nice set back to life.

I was calling local Samsung service, they absolutely have no spare
parts for such an old set from 2004/2005. They even have problems to
get spare parts to one year old sets... That's unbeliveable!
How can they offer that bad customer service. All they want to is
selling new sets appearently.

Regards
PAF


If you find a pressure sensitive BGA or similar IC, bits of rubber, wooden
wedges and cable ties around the IC and through a known, maybe multilayer
track-clear, section of pcb could give a bodge fix
 
On 19 Feb, 20:55, PlainBil...@yahoo.com wrote:
On Fri, 19 Feb 2010 01:30:03 -0800 (PST), powerampfreak

powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF

Can you read schematics?  The service manual for that set appears to
be available here:http://www.nodevice.com/manual/Samsung/page54.html

This definitely sounds like a scalar problem; not a driver or panel
issue.  Many manufacturers use Samsung panels and drive electronics in
their plasma sets.  The actual video processing is handled on a single
card designed and manufactured by the company whose name will appear
on the finished product.  I would not be optomistic of this being
repairable at the component level.  The video processing card consists
of a number of fairly complex processors working together.

PlainBill
Click to expand...
I'm familiar with schematics, I'm working my electronics, but not
plasma TV's unfortunately..
I did buy the service manual for the TV, at nodevice.com. Thanks for
the link!
Unfortunately, the service manual wasn't complete, the smps part and
output driver parts were missing,
but it seems most of the video processing board is there.
I suspect one of those processors to be the problem:
ASI501 which isn't possible to desolder (legs are underneath)
GENESIS FL12310 (possible to desolder)
I guess one of these ic's is the scaler.

In case, anyone has a complete board for no use, I'm interested (not
too optimistic...)

Board: NELSON
Code: BN41-00452 C
Rev: MP 1.4 (2004-08-19)

When having no input source connected, the screen is ALL blue. (all
lines OK)
Pressing MENU, it all looks briliant.
Connecting a video source, the picture has the "vertical lines"
problem. (still menu and all OSD is ok)
Also, I noticed, when having no input source connected (blue screen)
and apply input source, then screen goes all black for one second,
before it displays the video. During this second, when screen is
black, it's possible to see the veritcal lines problem very faint in
the black screen aswell.

As Plainbill said, I'm also starting to loose my optimism in getting
this nice set back to life.

I was calling local Samsung service, they absolutely have no spare
parts for such an old set from 2004/2005. They even have problems to
get spare parts to one year old sets... That's unbeliveable!
How can they offer that bad customer service. All they want to is
selling new sets appearently.

Regards
PAF
 
On 20 Feb, 13:29, "N_Cook" <dive...@tcp.co.uk> wrote:
powerampfreak <powerampfr...@hotmail.com> wrote in message

news:b6045eee-7954-4241-8e60-4b67bb278956@g26g2000yqn.googlegroups.com...
On 19 Feb, 20:55, PlainBil...@yahoo.com wrote:



On Fri, 19 Feb 2010 01:30:03 -0800 (PST), powerampfreak

powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF

Can you read schematics? The service manual for that set appears to
be available here:http://www.nodevice.com/manual/Samsung/page54.html

This definitely sounds like a scalar problem; not a driver or panel
issue. Many manufacturers use Samsung panels and drive electronics in
their plasma sets. The actual video processing is handled on a single
card designed and manufactured by the company whose name will appear
on the finished product. I would not be optomistic of this being
repairable at the component level. The video processing card consists
of a number of fairly complex processors working together.

PlainBill

I'm familiar with schematics, I'm working my electronics, but not
plasma TV's unfortunately..
I did buy the service manual for the TV, at nodevice.com. Thanks for
the link!
Unfortunately, the service manual wasn't complete, the smps part and
output driver parts were missing,
but it seems most of the video processing board is there.
I suspect one of those processors to be the problem:
ASI501 which isn't possible to desolder (legs are underneath)
GENESIS FL12310 (possible to desolder)
I guess one of these ic's is the scaler.

In case, anyone has a complete board for no use, I'm interested (not
too optimistic...)

Board: NELSON
Code:  BN41-00452 C
Rev:    MP 1.4 (2004-08-19)

When having no input source connected, the screen is ALL blue. (all
lines OK)
Pressing MENU, it all looks briliant.
Connecting a video source, the picture has the "vertical lines"
problem. (still menu and all OSD is ok)
Also, I noticed, when having no input source connected (blue screen)
and apply input source, then screen goes all black for one second,
before it displays the video. During this second, when screen is
black, it's possible to see the veritcal lines problem very faint in
the black screen aswell.

As Plainbill said, I'm also starting to loose my optimism in getting
this nice set back to life.

I was calling local Samsung service, they absolutely have no spare
parts for such an old set from 2004/2005. They even have problems to
get spare parts to one year old sets... That's unbeliveable!
How can they offer that bad customer service. All they want to is
selling new sets appearently.

Regards
PAF

If you find a pressure sensitive BGA or similar  IC, bits of rubber, wooden
wedges and cable ties around the IC and through a known, maybe multilayer
track-clear, section of pcb could give a bodge fix
Click to expand...
I did test to apply pressure to all of the ic's on the video
processing board without any difference. I was out of freeze spray,
maybe that could give some hints which ic is bad..
But. the failure shouldn't be in the smps / X-Y screen drivers or
similair.. It's still most "hot" in the video processing parts?
 
On Sat, 20 Feb 2010 04:21:41 -0800 (PST), powerampfreak
<powerampfreak@hotmail.com> wrote:

On 19 Feb, 20:55, PlainBil...@yahoo.com wrote:
On Fri, 19 Feb 2010 01:30:03 -0800 (PST), powerampfreak

powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF

Can you read schematics?  The service manual for that set appears to
be available here:http://www.nodevice.com/manual/Samsung/page54.html

This definitely sounds like a scalar problem; not a driver or panel
issue.  Many manufacturers use Samsung panels and drive electronics in
their plasma sets.  The actual video processing is handled on a single
card designed and manufactured by the company whose name will appear
on the finished product.  I would not be optomistic of this being
repairable at the component level.  The video processing card consists
of a number of fairly complex processors working together.

PlainBill

I'm familiar with schematics, I'm working my electronics, but not
plasma TV's unfortunately..
I did buy the service manual for the TV, at nodevice.com. Thanks for
the link!
Unfortunately, the service manual wasn't complete, the smps part and
output driver parts were missing,
but it seems most of the video processing board is there.
I suspect one of those processors to be the problem:
ASI501 which isn't possible to desolder (legs are underneath)
GENESIS FL12310 (possible to desolder)
I guess one of these ic's is the scaler.

In case, anyone has a complete board for no use, I'm interested (not
too optimistic...)

Board: NELSON
Code: BN41-00452 C
Rev: MP 1.4 (2004-08-19)

When having no input source connected, the screen is ALL blue. (all
lines OK)
Pressing MENU, it all looks briliant.
Connecting a video source, the picture has the "vertical lines"
problem. (still menu and all OSD is ok)
Also, I noticed, when having no input source connected (blue screen)
and apply input source, then screen goes all black for one second,
before it displays the video. During this second, when screen is
black, it's possible to see the veritcal lines problem very faint in
the black screen aswell.

As Plainbill said, I'm also starting to loose my optimism in getting
this nice set back to life.

I was calling local Samsung service, they absolutely have no spare
parts for such an old set from 2004/2005. They even have problems to
get spare parts to one year old sets... That's unbeliveable!
How can they offer that bad customer service. All they want to is
selling new sets appearently.

Regards
PAF

A quick lecture on how plasma sets are built. Samsung has a division
Click to expand...
that produces plasma panels. These are wholesaled as a 'display unit'
consisting of the panel, drivers, sustain boards, and a power suppy.
The power supply is customized for the particular wholesale customer.
The customer then adds a case, signal input card, audio amp, speakers,
etc. This results in a TV where physically most of the parts are not
under the manufacturer's control, and consequently schematics that
don't cover the whole TV.

As an aside, I just repaired a Philips plasma set, based on a
Samsung panel. The schematics are available, but only covered the
parts supplied by Philips. Virtually all of the processing was
handled on the Small Signal Board. The schematic for it ran to more
than 12 pages.

I'm not familiar with Samsung's TVs, but the Philips schematics
identify a part refered to as the 'scalar'. I would say that it is
very likely that the problem is in that part.

Parts availability has been a problem at least since the building of
the Pyramids. Imagine ordering a new stone from the quarry.

PlainBill
 
On 20 Feb, 18:53, PlainBil...@yahoo.com wrote:
On Sat, 20 Feb 2010 04:21:41 -0800 (PST), powerampfreak



powerampfr...@hotmail.com> wrote:
On 19 Feb, 20:55, PlainBil...@yahoo.com wrote:
On Fri, 19 Feb 2010 01:30:03 -0800 (PST), powerampfreak

powerampfr...@hotmail.com> wrote:
Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF

Can you read schematics?  The service manual for that set appears to
be available here:http://www.nodevice.com/manual/Samsung/page54.html

This definitely sounds like a scalar problem; not a driver or panel
issue.  Many manufacturers use Samsung panels and drive electronics in
their plasma sets.  The actual video processing is handled on a single
card designed and manufactured by the company whose name will appear
on the finished product.  I would not be optomistic of this being
repairable at the component level.  The video processing card consists
of a number of fairly complex processors working together.

PlainBill

I'm familiar with schematics, I'm working my electronics, but not
plasma TV's unfortunately..
I did buy the service manual for the TV, at nodevice.com. Thanks for
the link!
Unfortunately, the service manual wasn't complete, the smps part and
output driver parts were missing,
but it seems most of the video processing board is there.
I suspect one of those processors to be the problem:
ASI501 which isn't possible to desolder (legs are underneath)
GENESIS FL12310 (possible to desolder)
I guess one of these ic's is the scaler.

In case, anyone has a complete board for no use, I'm interested (not
too optimistic...)

Board: NELSON
Code:  BN41-00452 C
Rev:    MP 1.4 (2004-08-19)

When having no input source connected, the screen is ALL blue. (all
lines OK)
Pressing MENU, it all looks briliant.
Connecting a video source, the picture has the "vertical lines"
problem. (still menu and all OSD is ok)
Also, I noticed, when having no input source connected (blue screen)
and apply input source, then screen goes all black for one second,
before it displays the video. During this second, when screen is
black, it's possible to see the veritcal lines problem very faint in
the black screen aswell.

As Plainbill said, I'm also starting to loose my optimism in getting
this nice set back to life.

I was calling local Samsung service, they absolutely have no spare
parts for such an old set from 2004/2005. They even have problems to
get spare parts to one year old sets... That's unbeliveable!
How can they offer that bad customer service. All they want to is
selling new sets appearently.

Regards
PAF

A quick lecture on how plasma sets are built.  Samsung has a division
that produces plasma panels.  These are wholesaled as a 'display unit'
consisting of the panel, drivers, sustain boards, and a power suppy.
The power supply is customized for the particular wholesale customer.
The customer then adds a case, signal input card, audio amp, speakers,
etc. This results in a TV where physically most of the parts are not
under the manufacturer's control, and consequently schematics that
don't cover the whole TV.

  As an aside, I just repaired a Philips plasma set, based on a
Samsung panel.  The schematics are available, but only covered the
parts supplied by Philips.  Virtually all of the processing was
handled on the Small Signal Board.  The schematic for it ran to more
than 12 pages.

  I'm not familiar with Samsung's TVs, but the Philips schematics
identify a part refered to as the 'scalar'.  I would say that it is
very likely that the problem is in that part.

Parts availability has been a problem at least since the building of
the Pyramids.  Imagine ordering a new stone from the quarry.

PlainBill
Click to expand...
I found what I believe is the scaler IC (ASI501) as spare part, but I
don't know who has the tools to change it.
At my work, we have heat gun soldering tools and microscopes, so other
IC's with 500 legs are possible to replace.
But not BGA's...
The service manual doesn't display the IC as "scaler", maybe you would
like to look at the schematics, and you may get an idea if I'm on the
right track?
The question is if there are lots of data stored in those processors
that needs to be flashed after replacement?
Or maybe the micro processor take care of all data.

Best regards
PAF
 
On Fri, 19 Feb 2010 01:30:03 -0800 (PST), powerampfreak
<powerampfreak@hotmail.com> put finger to keyboard and composed:

Hi all.
I've a plasma TV which has a problem with the picture. If you think of
verticle lines through the entire screen, I would say the 1st, 5th and
10th is not lit. BUT, menus and on-screen displays work perfect giving
a correct picture. But which ever input source I choose, (both scarts
or composite video) the picture will have the "vertical lines"
problem. So, why is OSD and menus work ok? There has be something in
the scaling / picture generation parts.
Anyone know of something useful where to check?
Best regards
PAF
Click to expand...
If you vary the aspect ratio, do the lines move?

Can the TV accept a DVI/HDMI input from a PC? If so, would it be
possible to create a test pattern for troubleshooting purposes? What
about a single vertical line with a user selectable colour and
position, that flashes on and off once per second??? That should make
the signal path easier to follow on a scope.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top