Re: Desktop case: phase 1

[derek@slab.isdn.uiuc.edu (Derek Taubert)]

In <4quknl$r7b@nnrp1.news.primenet.com> Bradley P. Von Haden wrote:

> Maybe I am wrong (vaguely recalling a thread somewhere about this
> topic), but I was under the impression that while the connectors on
> ADB and S-video cables were the same, the electrical properties
> (resistance, etc) of the cables were different.
> 
> The upshot of this being that while S-video cables might work in
> certain situations, they did not work in all situations.

I'm sure you're right about this.  S-Video has two signals which both need 
individual 75 ohm transmission lines.  The other 2 pins are ground, and 
connected to the shielding around the two signals.  So in an S-Video cable 
you have two coax cables, while an ADB cable has 4 individual wires.  The 
shielding of the 75 ohm lines will most likely be isolated from each other, 
so you do actually have 4 separate current paths (so it MIGHT work), but the 
crosstalk and impedance is likely to mess up the ADB digital signal.

Just buy the right cable for the job.  I'm sure you can find a mac place that 
sells exactly what you're looking for.

--
Derek Taubert - http://slab.isdn.uiuc.edu/~derek
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