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

[Texx]

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.

The original EIA RS-232 spec was written for Cat-2 cable which was not much
more than twisted doorbell wire.
Data speeds improved somewhere between CAT-2 & CAT-3.
The first ARPANET links I believe were 19k before later upgrading to 56k.

The telco industry adopted an Amphenol connector for 25 pair cables.
Later, Centronics adopted a shorter version of the same connector (36
pin/18 pair)
I still run into morons who call them all Centronics (25 pair, 28 pair,
even DB-25)
This was sad when a telco employee told me that the phone co adopted the
connector after Centronics did.

Further complicating things, SCSI has been done on a 25 pair amphenol and a
DB-25.
When I used a DB25 cable to connect serial ports, I got yelled at "You cant
use that cable!  Thats a PARALLEL cable!"
Oh yeah, after the demise of the centronics printer port they used a DB25
for THAT too!

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


-- 

R "Texx" Woodworth
Sysadmin, E-Postmaster, IT Molewhacker
"Face down, 9 edge 1st, roadkill on the information superdata highway..."
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