green dots on plasma tv set
 

Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases
if scene persist dark.
How I can check?
Thanks and excuse me for my english.

Bye.


--
Prima di rispondermi devi togliere le dita dal naso!!! :-)

green dots on plasma tv set
 

On Sun, 22 Mar 2009 00:29:36 +0100, Telespalla Bob
wrote:

:Hi, I have gained one LG based Plasma TV set.
:This TV is maked around model 42V5 chassis.
:In dark scenes, I see high quantity of green dots that is very numerous
:immediately after brightness change from light to dark, then decreases
:if scene persist dark.
:How I can check?
:Thanks and excuse me for my english.
:
:Bye.


Back a few years LG plasma 42 inch TV's suffered from a "green line" symptom.
Usually off to one side (can't remember which side) a thin vertical green line
stretched from top to bottom and as it worsened an additional parallel green
line would start to appear.

The only solution is a replacement of the plasma display.

I had an old war veteran friend who paid about $4000 for one of these sets and
he had owned it for about 2-1/2 years (long past the warranty period) when it
developed the symptom. After giving LG a good sob story they agreed to replace
the plasma screen at minimal cost (about $200). The real repair cost was well
over $1000, which he could definitely not afford. Repairing the set allowed him
to sell the set for $1000 but otherwise it was not worth a bean.

green dots on plasma tv set
 

"Telespalla Bob" wrote in message
. ..
Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases if
scene persist dark.
How I can check?
Thanks and excuse me for my english.

Bye.


--
Prima di rispondermi devi togliere le dita dal naso!!! :-)



Sounds like a Vs adjustment...

Mark Z.

green dots on plasma tv set
 

Mark Zacharias ha scritto:
"Telespalla Bob" wrote in message
. ..
Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very
numerous immediately after brightness change from light to dark, then
decreases if scene persist dark.
How I can check?
Thanks and excuse me for my english.

Bye.


--
Prima di rispondermi devi togliere le dita dal naso!!! :-)



Sounds like a Vs adjustment...

Mark Z.

thanks, I try.
how I can adjust Vs? and how much voltage?
I have not schematics...

bye.


--
Prima di rispondermi devi togliere le dita dal naso!!! :-)

green dots on plasma tv set
 

Ross Herbert ha scritto:
On Sun, 22 Mar 2009 00:29:36 +0100, Telespalla Bob
wrote:

:Hi, I have gained one LG based Plasma TV set.
:This TV is maked around model 42V5 chassis.
:In dark scenes, I see high quantity of green dots that is very numerous
:immediately after brightness change from light to dark, then decreases
:if scene persist dark.
:How I can check?
:Thanks and excuse me for my english.
:
:Bye.


Back a few years LG plasma 42 inch TV's suffered from a "green line" symptom.
Usually off to one side (can't remember which side) a thin vertical green line
stretched from top to bottom and as it worsened an additional parallel green
line would start to appear.

The only solution is a replacement of the plasma display.

I had an old war veteran friend who paid about $4000 for one of these sets and
he had owned it for about 2-1/2 years (long past the warranty period) when it
developed the symptom. After giving LG a good sob story they agreed to replace
the plasma screen at minimal cost (about $200). The real repair cost was well
over $1000, which he could definitely not afford. Repairing the set allowed him
to sell the set for $1000 but otherwise it was not worth a bean.


thanks, but I have green dots, not green line on my display.



--
Prima di rispondermi devi togliere le dita dal naso!!! :-)

green dots on plasma tv set
 

"Mark Zacharias" wrote in message
...
"Telespalla Bob" wrote in message
. ..
Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases if
scene persist dark.
How I can check?
Thanks and excuse me for my english.

Bye.


--
Prima di rispondermi devi togliere le dita dal naso!!! :-)



Sounds like a Vs adjustment...

Mark Z.

Seconded ...

Arfa

green dots on plasma tv set
 

"Telespalla Bob" wrote in message
. ..
Mark Zacharias ha scritto:
"Telespalla Bob" wrote in message
. ..
Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases
if scene persist dark.
How I can check?
Thanks and excuse me for my english.

Bye.


--
Prima di rispondermi devi togliere le dita dal naso!!! :-)



Sounds like a Vs adjustment...

Mark Z.

thanks, I try.
how I can adjust Vs? and how much voltage?
I have not schematics...

bye.


--
Prima di rispondermi devi togliere le dita dal naso!!! :-)



Usually just below 200 volts; adjust to lower the voltage until the speckes
disappear. If no change, return the adjustment to it's original position.

Just exactly where this is located in your unit I don't know. In Samsung
models it is usually in one corner of the Y main board, near a Vs test
point.


Mark Z.

green dots on plasma tv set
 

On Sun, 22 Mar 2009 11:05:07 -0500, "Mark Zacharias"
put finger to keyboard and composed:

"Telespalla Bob" wrote in message
...
Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases if
scene persist dark.
How I can check?

Sounds like a Vs adjustment...

Mark Z.

Ditto.

The Serviceman column in the April 2009 issue of Silicon Chip Magazine
identifies the problem as a V Setup adjustment. FWIW, on the
PDP42V72462 chassis it is VR1 on the Y Sus board.

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

green dots on plasma tv set
 

Franc Zabkar ha scritto:
On Sun, 22 Mar 2009 11:05:07 -0500, "Mark Zacharias"
put finger to keyboard and composed:

"Telespalla Bob" wrote in message
. ..
Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases if
scene persist dark.
How I can check?

Sounds like a Vs adjustment...

Mark Z.

Ditto.

The Serviceman column in the April 2009 issue of Silicon Chip Magazine
identifies the problem as a V Setup adjustment. FWIW, on the
PDP42V72462 chassis it is VR1 on the Y Sus board.

- Franc Zabkar


Thanks to all.
If Vs and VR1 adjustment does not solve the problem, is it possible that
this is an electrolytic capacitor failure?

Thansk.


--
Prima di rispondermi devi togliere le dita dal naso!!! :-)

green dots on plasma tv set
 

"Telespalla Bob" wrote in message
. ..
Franc Zabkar ha scritto:
On Sun, 22 Mar 2009 11:05:07 -0500, "Mark Zacharias"
put finger to keyboard and composed:

"Telespalla Bob" wrote in message
. ..
Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases
if scene persist dark.
How I can check?

Sounds like a Vs adjustment...

Mark Z.

Ditto.

The Serviceman column in the April 2009 issue of Silicon Chip Magazine
identifies the problem as a V Setup adjustment. FWIW, on the
PDP42V72462 chassis it is VR1 on the Y Sus board.

- Franc Zabkar


Thanks to all.
If Vs and VR1 adjustment does not solve the problem, is it possible that
this is an electrolytic capacitor failure?

Thansk.


Anything's *possible* I suppose, but in this case, I would say that it's
pretty unlkely. The symptoms you describe are very typical of mis-adjustment
of Vs, and I would give correcting that, a better than 90% chance of success
....

Arfa

--
Prima di rispondermi devi togliere le dita dal naso!!! :-)

green dots on plasma tv set
 

Arfa Daily ha scritto:
"Telespalla Bob" wrote in message
. ..
Franc Zabkar ha scritto:
On Sun, 22 Mar 2009 11:05:07 -0500, "Mark Zacharias"
put finger to keyboard and composed:

"Telespalla Bob" wrote in message
. ..
Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases
if scene persist dark.
How I can check?
Sounds like a Vs adjustment...

Mark Z.
Ditto.

The Serviceman column in the April 2009 issue of Silicon Chip Magazine
identifies the problem as a V Setup adjustment. FWIW, on the
PDP42V72462 chassis it is VR1 on the Y Sus board.

- Franc Zabkar

Thanks to all.
If Vs and VR1 adjustment does not solve the problem, is it possible that
this is an electrolytic capacitor failure?

Thansk.


Anything's *possible* I suppose, but in this case, I would say that it's
pretty unlkely. The symptoms you describe are very typical of mis-adjustment
of Vs, and I would give correcting that, a better than 90% chance of success
...

Arfa
--
Prima di rispondermi devi togliere le dita dal naso!!! :-)




I have tryed to adjust Vs.
In back of panel there it is a label that says: Vs=190V

I tried up to 195V but green dots does not disappears.
I also tried to adjust under 180V, and green dots decreases, but
together with screen brightness and detail...

If not capacitors, how I can try?

Thanks.




--
Prima di rispondermi devi togliere le dita dal naso!!! :-)

green dots on plasma tv set
 

"Meat Plow" wrote in message
...
On Sun, 22 Mar 2009 00:29:36 +0100, Telespalla Bob
wrote:

Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases
if scene persist dark.
How I can check?
Thanks and excuse me for my english.

Bye.

Probably the PDP not erasing the pixels fast enough. If this is the
case the only way to repair is to replace the PDP.

This set is made by Hyundai.


I agree at this point - an aged panel.

Mark Z.

green dots on plasma tv set
 

"Mark Zacharias" wrote in message
...
"Meat Plow" wrote in message
...
On Sun, 22 Mar 2009 00:29:36 +0100, Telespalla Bob
wrote:

Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases
if scene persist dark.
How I can check?
Thanks and excuse me for my english.

Bye.

Probably the PDP not erasing the pixels fast enough. If this is the
case the only way to repair is to replace the PDP.

This set is made by Hyundai.


I agree at this point - an aged panel.

Mark Z.

Agreed also. The clue is probably that it gets better as Vs is turned down,
but not before the picture starts to deteriorate ...

Arfa

green dots on plasma tv set
 

Arfa Daily ha scritto:
"Mark Zacharias" wrote in message
...
"Meat Plow" wrote in message
...
On Sun, 22 Mar 2009 00:29:36 +0100, Telespalla Bob
wrote:

Hi, I have gained one LG based Plasma TV set.
This TV is maked around model 42V5 chassis.
In dark scenes, I see high quantity of green dots that is very numerous
immediately after brightness change from light to dark, then decreases
if scene persist dark.
How I can check?
Thanks and excuse me for my english.

Bye.
Probably the PDP not erasing the pixels fast enough. If this is the
case the only way to repair is to replace the PDP.

This set is made by Hyundai.

I agree at this point - an aged panel.

Mark Z.

Agreed also. The clue is probably that it gets better as Vs is turned down,
but not before the picture starts to deteriorate ...

Arfa




yes, picture panel has several work hours, but I not remember that green
pixels was already present before IPM fail.
This is a common defect due to aging? (I never put hands in plasma tv set)
I have checked ripples to Vs line with oscilloscope ac coupled, and I
see most spikes (about 3-4Vpp)... for this thought about the capacitors.

conclusions?

Thanks.


--
Prima di rispondermi devi togliere le dita dal naso!!! :-)