[mythtv-users] How I got great quality TV-out on my nVidia MX4000

[Cory Papenfuss]

>>  	I've mentioned what I did in the past, starting with
>> http://www.gossamer-threads.com/lists/mythtv/users/45910#45910
>> Basically built up the circuit in the AD724 datasheet.
>
> Seems strange that there is no commercial "off the shelf" products doing
> this.  Perhaps there is.  I will have to search this afternoon when I
> get a minute.
>
 	I think that a previous post explains why.  Basically, it's 
complicated to get a modeline to work exactly correctly, and when you *do* 
have a correct one, it doesn't work on a regular VGA monitor.  It's 
possible to damage the TV and/or VGA monitor.

 	There already exists a commercial product that does effectively 
the same thing... a VGA/YPbPr transcoder box.  It should work at 480i and 
could provide even better quality than going to NTSC.  Of course, it 
requires component in on the tv.

>> I've thought of making a
>> slightly nicer one (with VGA loop, though, etc).
>
> What would the loop through provide?
>
 	Keep a VGA monitor connected to it so it would be easy to switch 
to another resolution for troubleshooting.

>> If there were enough
>> interest I suppose I could finish it off and send off for a limited run of
>> PCBs.
>
> If you can do that you might want to think about filling a possible
> market void.  Inventions are the way to get rich.  :-)
>
 	I wouldn't call it an invention.  More of a copycat from what's 
already been done.

>>  	Yeah, except that you get garbage until X comes up.  The VGA on
>> bootup is basically 480p, which doesn't exactly work on S-vid.  Aside from
>> that detail, it's great.
>
> Small detail and to be expected.
>
 	Small, perhaps.  Irritating, absolutely.  Also, beyond the 
understanding of 99% of the PC-buying public (MythTV crowd is higher 
technically-saavy than most).  To most people, the tradeoffs involved are 
too subtle to be appreciated, but rather they'll get pissed when it 
doesn't "just work."  They'll get even *more* pissed when they program the 
modeline wrong, let the magic smoke out of their TV or monitor, and get an 
"I told you so" from the person that sold it to them.  Just tell them, 
"Run it at 1024x768, crank the flicker filter up to maximum, and enjoy."

 	Pffft!
(Boy, when did I become such a surly bastard?  :)

-Cory

*************************************************************************
* Cory Papenfuss                                                        *
* Electrical Engineering candidate Ph.D. graduate student               *
* Virginia Polytechnic Institute and State University                   *
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