[conspire] RS-232-C (was: Re: DE-9, not DB-9 (was: conspire list hacked?))

[Michael Paoli]

> From: Texx <texxgadget at gmail.com>
> Subject: Re: [conspire] RS-232-C (was: Re: DE-9, not DB-9 (was:  
> conspire list hacked?))
> Date: Fri, 8 Mar 2019 19:41:26 -0800

> Improvements in cable enabled pushing the RS232 standard.
> When you look at those twisted wire pairs, you are looking at the magic.
> The specs of the cable depend on the number of twists per foot and the
> insurance that the spacing between
> the surfaces of the wires inside the insulation remaining fairly constant.
> This is the difference between the various "CAT" numbers.

There's more to it than just that.  The types of materials use also
matter a lot.  Most notably the dielectric properties vary.
Low-capacitance ("lo cap") cabling uses significantly different
insulation around the conductors - even if everything else about
the conductors is the same.  Think of a simple basic
capacitor - a pair of metal plates.  Change nothing else but
what insulating materials are placed between those plates,
and the capacitance of that capacitor can be changed quite radically ...
well, same deal with the cabling - change the insulating materials
and the capacitance between conductors can be changed quite substantially.

> People who think they know everything annoy the hell out of those of us who
> DO!

Nobody knows everything.