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From: powerampfreak on 19 Feb 2010 04:30
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
From: powerampfreak on 19 Feb 2010 04:34
On 19 Feb, 10:30, powerampfreak <powerampfr...(a)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.
From: N_Cook on 19 Feb 2010 05:41
powerampfreak <powerampfreak(a)hotmail.com> wrote in message
news:f46cbc75-bb0c-44b2-b49d-e56fae83d5f8(a)v20g2000yqv.googlegroups.com...
> On 19 Feb, 10:30, powerampfreak <powerampfr...(a)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?


From: powerampfreak on 19 Feb 2010 10:32
On 19 Feb, 11:41, "N_Cook" <dive...(a)tcp.co.uk> wrote:
> powerampfreak <powerampfr...(a)hotmail.com> wrote in message
>
> news:f46cbc75-bb0c-44b2-b49d-e56fae83d5f8(a)v20g2000yqv.googlegroups.com...
>
>
>
> > On 19 Feb, 10:30, powerampfreak <powerampfr...(a)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






From: N_Cook on 19 Feb 2010 10:55
powerampfreak <powerampfreak(a)hotmail.com> wrote in message
news:978ad71c-8228-40a0-9df7-cd22c7b7902b(a)l26g2000yqd.googlegroups.com...
> On 19 Feb, 11:41, "N_Cook" <dive...(a)tcp.co.uk> wrote:
> > powerampfreak <powerampfr...(a)hotmail.com> wrote in message
> >
> >
news:f46cbc75-bb0c-44b2-b49d-e56fae83d5f8(a)v20g2000yqv.googlegroups.com...
> >
> >
> >
> > > On 19 Feb, 10:30, powerampfreak <powerampfr...(a)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


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