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Annoying TV disturbance

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root

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Jan 3, 2016, 7:00:01 PM1/3/16
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I have recently become aware (bothered by) what appears to be
a line moving up across the TV screen. The TV is a Samsung
4K with HDMI input, and the line that moves up the screen
appears to be a missing scan line.

The TV derives its input from a linux computer running
mplayer, and the video card is an NVidia 610. The
HDMI output goes to the TV and the vga output goes to
a monitor which I can see while the TV is playing.

The discontinuity on the TV screen is not replicated
on the monitor screen.

The moving line appears every few minutes.

I was not conscious of the problem prior to a shutdown
of the video server to increase the storage capacity.

Any suggestion of what might cause the effect, or questions
that may further clarify the phenomenon would be appreciated.

Kenny Cargill

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Jan 3, 2016, 7:56:39 PM1/3/16
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Sounds like a ground loop hum bar, look here:
http://www.cinemasource.com/articles/gnd_loop.pdf
Move cables away from each other and don't use cheap co-ax, HDMI etc.
cables.

Kenny

"root" wrote in message news:n6cclq$anm$1...@news.albasani.net...
--- news://freenews.netfront.net/ - complaints: ne...@netfront.net ---

stra...@yahoo.com

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Jan 3, 2016, 8:45:25 PM1/3/16
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On Sunday, January 3, 2016 at 4:56:39 PM UTC-8, Kenny Cargill wrote:
> Sounds like a ground loop hum bar, look here:
> http://www.cinemasource.com/articles/gnd_loop.pdf
> Move cables away from each other and don't use cheap co-ax, HDMI etc.
> cables.
>
> Kenny
>

Cinemasource has an RF isolator for which they want $50.
I bought 3 for $25 from these guys.

http://www.rmscommunications.net/pdf/MI2120VPG69&70.pdf

My hum was in the audio from the RF feed. The isolator
cleaned it all up.


Adrian Caspersz

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Jan 4, 2016, 6:41:07 AM1/4/16
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Two tests.

Try HDMI from another source. If same fault here, blame Samsung and call
their support. Or maybe cabling interference issues.

Or temporarily try another OS on your hardware. A linux live CD would do.

If it doesn't occur on the other OS, then grab the video timing info
from that, and compare with your current OS.

xvidtune -show

--
Adrian C

John-Del

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Jan 4, 2016, 10:04:49 AM1/4/16
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The fact that the line moves in that manner pretty much eliminates the display as a possibility, but it could still be a main board issue.

When the line appears, put up the TVs own menu. If the line disturbs the menu, it's a TV issue.

root

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Jan 4, 2016, 2:38:25 PM1/4/16
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Kenny Cargill <m...@privacy.net> wrote:
> Sounds like a ground loop hum bar, look here:
> http://www.cinemasource.com/articles/gnd_loop.pdf
> Move cables away from each other and don't use cheap co-ax, HDMI etc.
> cables.
>
> Kenny

Your analysis is correct. I re-routed the hdmi cable and the problem
is gone. Thanks to all who responded.

root

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Jan 4, 2016, 2:39:03 PM1/4/16
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Fortunately for me re-routing was sufficient.

root

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Jan 4, 2016, 2:40:54 PM1/4/16
to
Adrian Caspersz <em...@here.invalid> wrote:
>
> Two tests.
>
> Try HDMI from another source. If same fault here, blame Samsung and call
> their support. Or maybe cabling interference issues.
>
> Or temporarily try another OS on your hardware. A linux live CD would do.
>
> If it doesn't occur on the other OS, then grab the video timing info
> from that, and compare with your current OS.
>
> xvidtune -show
>

Thanks for responding. Hum seems to have been the problem since
re-routing the hdmi cable fixed it.

root

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Jan 4, 2016, 2:42:20 PM1/4/16
to
John-Del <ohg...@aol.com> wrote:
>
> The fact that the line moves in that manner pretty much eliminates the display as a possibility, but it could still be a main board issue.
>
> When the line appears, put up the TVs own menu. If the line disturbs the menu, it's a TV issue.

Hum seems to have been the problem. Now that you mention it,
there never has been a problem in the menu displays. I should
have thought of that.
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