[mythtv-users] Refresh line being seen

[Paulin]

On Sat, Feb 14, 2009 at 1:35 PM, Allen Edwards <allen.p.edwards at gmail.com>wrote:

>
>
> On Sat, Feb 14, 2009 at 10:22 AM, Brian Wood <beww at beww.org> wrote:
>
>> On Saturday 14 February 2009 11:02:41 MrVining wrote:
>> > On Feb 14, 2009, at 9:26 AM, Paulin wrote:
>> > > I'm having an old problem reappear after upgrading the NVidia
>> > > driver and then downgrading.  Can't seem to figure it out.
>> > >
>> > > 1. Upgraded to 180.22 NVidia driver.
>> > > 2. Eventually downgraded back to 180.16 driver.
>> > > 3. Put the .nvidia-settingrc file back from before the upgrade
>> > >
>> > > Now whenever watching a recorded program there is a thin line
>> > > scrolling down the screen every minute or so.
>> > >
>> > > Can anyone tell me what I should be looking at to correct this.  I
>> > > thought it was caused by the Nvidia settings but since they are
>> > > back to what they were before I updated/downgraded the driver I'm
>> > > not sure why it's happening.
>> > >
>> > > Any help would be appreciated.
>> > >
>> > > Thanks,
>> > > steve
>> >
>> > Is it possible that it is not driver related?  Has there been any
>> > physical changes made to the system.  I hear line slowly scrolling
>> > down the screen and I still jump right to grounding issue (retired
>> > cable guy).
>>
>> With NTSC at least, a horizontal line scrolling slowly *up* the screen
>> indicates 60 or 120 Hz. hum. The rate is the difference between the
>> vertical
>> rate being precisely 60Hz, and what it really is with NTSC color (in other
>> words, if 3.579545 was in fact 3.600000, then the bar would be
>> stationary).
>>
>> A grounding issue would thus create a moving up bar, unless the scan rate
>> of
>> the video was far enough from 60Hz. to create a downward motion of the
>> bar.
>>
>> I tend to agree that the OP does not have a driver issue, more likely some
>> sort of interference in the machine itself, the monitor, or the cabling,
>> or
>> some sort of common mode (ie: grounding) problem.
>>
>> --
>> beww
>
>
> By ground problem, likely it means that there is a difference between the
> computer ground and the TV ground.  So, in this case you may not have done
> anything to the computer but if you plugged the TV in to a different slot or
> changed your antenna setup it could explain it.
>
> If you have cable, it could even be that the cable guy came by while you
> were not looking and grounded the feed.
>
> I had to run power from my projector to my surround setup to get rid of a
> line like that. Now everything is on the same circuit.  I also ground my
> antenna to that same sub panel.
>
> Allen
>
>

OK now I'm even more confused.  Sorry :)

Anyway this setup has been this way for a few months (November) and working
until yesterday night when I did a few things to the box (removed GNome
Network Manager, Attempted to upgrade the NVIDIA driver to 180.22, and
rebuilt trunk.

The Myth Box (Backend/Frontend) was not really touched other then to plug in
a CRT for some initial work with the Driver setup.

The box is plug into a surge protector power strip that the stereo, TV, DVD
and TIVO are all plugged in.  The cable coming in, is split (3-way) and
feeds the Tivo, and the two tuner cards in my mythbox.

The line that I have scrolls down only.  When I first configured my MythBox
I had this issue and it was fixed when I got the NVidia settings correct.
That may have been a cooincent.

If fixing the grounding issue what part should I look at changing.

Thanks and sorry for my ignorance.
steve
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