[mythtv-users] No signal on TV with Audio Authority

Mitko Haralanov voidtrance at comcast.net
Wed May 4 18:36:37 UTC 2005

On Wed, 4 May 2005 14:13:57 -0400 (EDT)
Cory Papenfuss <papenfuss at juneau.me.vt.edu> wrote:

> I have seen some transcoder boxes that are picky on the polarity 
> of the sync signal they are sent.  Try adding/changing -vsync -hsync 
> +vsync +hsync at the end of the modeline.

You can probably tell that I know next to nothing about video signal!!

The modelines that I am using were taken from posts of people using the
same model of Audio Authority boxes, so I am thinking that should be
ok. Now, I am not sure whether the TV cares about the polarity as

> You should also make sure that 
> the modeline is producing correct frequency output.

I am not sure how to verify that? The PC monitor is work but the TV
does not show anything. The frequencies that the modelines are using
seem to be in the right ranges for the TV.

> If it were me looking to see if it worked, I would put the output 
> (Y in particular) on an oscilloscope and see if it's got signal and sync.

We have an oscilloscope at work and I might be able to ask some of the
more savvy people to help me check it.

Mitko Haralanov
voidtrance at comcast dot net

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