ROBERT SAYRE wrote in a message to ROY J. TELLASON:

RJT> I know that when you're up around 9600 and higher speeds cabling gets 
RJT> more critical and allowable length gets way shorter.

RS>  If you go RS-485 you can go thousands of feet
RS> at 9600 baud. We're doing it.

I forget which of the specs -485 is,  there's a couple of them in there. 
The TeleVideo box I have has some interfaces on it,  I forget if they're
RS-422 or -485,  they're a balanced line that uses a shielded pair,  I
think.

But if I needed to go that far at 9600,  I have a pair of 4-wire modems
that'll do the trick.    They were made for leased lines or
something,  I dunno,  but are not typical modems,  not at all,  and
intended for use with a 4-wire link.

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