Panasonic: Solution to Moire, Rainbow, Stripes...

Hi!
Since there still seem to be some owners of Pannies who have the same problem with their TV I've had with my TX32PK20 for over 20 months, I want to share this with you.
It was just yesterday that I found this forum and I got to say BIG THANKS to Mr. D, who posted the solution:

JUST DEFOCUS THE TUBE.

I did it and it worked out perfectly. No more moire at all.
There was also no loss in sharpness, at least none I could see.
I can't believe that those people, who looked over the set twice and could not get rid of those stripes call themselves Panasonic service engineers. Should have been an easy task for them.
I do not recommend to do it yourself though, because it's got to be done with the chassis open and the set running, touching the wrong parts will KILL YOU.
Just get a service engineer to adjust the focus and tell him when it's ok.

Hope this will be helpful to somebody...

TKone

[Midge]

Call me stupid, but what is a 'Moire' effect on a TV??

I would never call you stupid for not knowing something I can't even describe properly. Aneeways, this is exactly the same problem I had:

Originally posted by MalcolmD
Anyone have any ideas on the following ;

On the screen of the Panasonic TV TX-32PK20 i can notice a very feint pattern of lines at the bottom of the screen. They are in a rainbow pattern that start at the bottom left of the screen and then arcs towards the centre and the back down to the bottom right. The picture itself is not distorted.

I initially wondered if it was due to interference from my other equipment that is connected, DVD, AMP, Sky Digital and Video. However if I unplug all these it is still noticeable.

And this is the technical explanation for it:

Originally posted by Mr.D
Ok problem is most likely moire patterning. This can happen on any tube apart from the sony trinitrons (or clones) which have a slot mask (or aperture grill!)instead of a dot mask. (they also have visible support wires on the tube)

I suspect the reason moire is becoming a problem on these sets is because they have to deal with different picture aspects and raster sizes and this is showing up some less than constant focusing on the scan beam or some variation in the dot-pitch of the shadowmask.

Moire on ANY TV set should be rectifiable by defocusing the scan beam slightly so that its slightly larger than the dotpitch of the shadow mask. I'm assuming for these sets this has been done at the factory but only with relevance to the centre of the screen (makes me think its the dot-pitch on the tube thats not uniform across the width of the face rather than the beam itself)

Take a look at this thread for an explanation..


What display will give PAL progressive?

[Midge]

Thanks....I think

I think that i have this problem, but my lines are mirrored top and bottom with stright line across the middle then they bend to form the rainbow shape. They also seem to pulse.
The straight lines seem to be the only ones that show up on pale or misty scenes, but not in just mode. The picture its self is fine.
Does this sound about right becasue i was starting to think i was imagining it!.

Thanks

[colesy]

I have a smiliar problem with my tx36pb50.
I don't think it's moire though.
I have diagonal lines which are lower on the left and higher on the right hand side.
They go all the way across the screen and appear to scroll down the screen, pause and then scroll back up.

So do you have any idea what causes it and what i can do to get rid of it ?

[colesy]

I have tried to defocus my TV and a still having problems.
I have no idea what causes it. I have heard of the scan coils can cause it, noisy power supply can cause it. I have been in contact with Panansonic, they have even had the Tv back. They say it is not faulty and within specification.

Panasonic have replied saying this
"Thank you for your e-mail.

In response I would explain that after consulting with our resident
technical department they advise that double screeded SCART leads are used
as this should stop the probles you have been having.

Kind regards,
Customer Support"

Don't know why they said this. All my scarts are high quality and even when there is just the uhf co-axial aerial connected, this still occurs.

[tricky_bob]

I have a TX-32PS12

Had it for about 12 months, It has been nothing but trouble. It has a Blue smudge in the top right hand corner, a Orange smudge in the lower right hand corner, Light horizontal lines across the whole screen visible only on light colours and 2 thick bands of grey from top to bottom visable only on very dark colours. I was told it was my UF signal but I now have SKY and it's still the same.

Panasonic told me it was my DVD player because they hadn't heard of Liteon (sold in those small shops called CURRYS !) So I got a Panasonic off my brother and it was the same !

I've has a dude come round and "fix" it 3 times and its still the same !

Thought I was buying quality when I spent £700 but the £35 second hand TV's I used to have were all golden compared to this pile.

I wont buy Panasonic again.

[Slimchandi]

I've noticed some very faint vertical banding, only noticable on white or bright screens when the camera pans from left to right or vice versa? Any idea what might be causing it?