Analogue video outputs available for mac mini?

Hi All,

I was wondering whether anybody knew anything about how the mac mini
provides an analogue video signal to s-video enabled devices?

I am aware that an external DVI to S-Video adaptor exists from Apple,
but it appears that its completely passive (just a cable) and no active
conversion is taking place between the available analogue RGB outputs
and the s-video format. Since RGB to s-video conversion is a
non-trivial exercise, based on the simplicity of the available adaptor,
is it possible that an analogue s-video output is available directly
from the mac mini via a known wiring arrangement? (and the hence the
adaptor). I am aware that the DVI connector includes analogue RGB
outputs (C1-4) but cannot see where the s-video comes from unless it's
proprietary info...

Reason for my interest is that I need eaxctly this adaptor cable but it
is not available from any local Apple distributors (South Africa) so I
figured, based on what appears to be a simple re-wiring exercise, to
make my own cable adaptor - anybody can help advise here? Be much
appreciated.

Thanks,

Jacek

On 2006-07-26 09:34:27 -0400, "Jacek" <jacek.RemoveThis@antfarm.co.za> said:

> Hi All,
>
> I was wondering whether anybody knew anything about how the mac mini
> provides an analogue video signal to s-video enabled devices?
>
> I am aware that an external DVI to S-Video adaptor exists from Apple,
> but it appears that its completely passive (just a cable) and no active
> conversion is taking place between the available analogue RGB outputs
> and the s-video format. Since RGB to s-video conversion is a
> non-trivial exercise, based on the simplicity of the available adaptor,
> is it possible that an analogue s-video output is available directly
> from the mac mini via a known wiring arrangement? (and the hence the
> adaptor). I am aware that the DVI connector includes analogue RGB
> outputs (C1-4) but cannot see where the s-video comes from unless it's
> proprietary info...
>
> Reason for my interest is that I need eaxctly this adaptor cable but it
> is not available from any local Apple distributors (South Africa) so I
> figured, based on what appears to be a simple re-wiring exercise, to
> make my own cable adaptor - anybody can help advise here? Be much
> appreciated.
>
> Thanks,
>
> Jacek

It's not that simple. The S-video signals are not there waiting to be
used. When the video adapter is plugged into the DVI port, the
graphics board recognizes it from the digital codes it sends back. It
then uses the three digital to analog converters, normally used for RGB
analog, to generate composite video, and the luminance and color
S-video signals. The adapter takes these from the RGB pins of the DVI
connector. I don't think there is any way to build your own adapter.
You should be able to get fast shipping from Apple if you pay extra.