[comp.dcom.modems] Looking for High Speed Modem

QWYELX@HUMBER.BITNET (Erone Quek) (10/19/90)

Hello All,

I am looking for a high speed modem (>512kbps) that will operate over
4-wire unloaded twisted pair (telephone cable) at a distance of 2.5 Km.

I have tried a pair of RAD/RND ASM-40, no luck.

Any suggestion will be more than appreciated.

Erone Quek

grr@cbmvax.commodore.com (George Robbins) (10/19/90)

In article <90Oct18.214428edt.57509@ugw.utcs.utoronto.ca> QWYELX@HUMBER.BITNET (Erone Quek) writes:
> 
> I am looking for a high speed modem (>512kbps) that will operate over
> 4-wire unloaded twisted pair (telephone cable) at a distance of 2.5 Km.
> 
> I have tried a pair of RAD/RND ASM-40, no luck.

You might try the RAD ASM-45, it seems a little less agressive and the
distance/speed curve might let you eek thru around 512KBPS / 2.5 KM,
while there's a good chance 256KBPS would work and be better than
nothing...

Beyond that, some T1 CSU/DSU devices can be used a short-haul modems 
but I suspect you get to about the same place on the distance / speed
curve and would need to add some kind of mid-line repeater.

I suppose there are problems with T1 (or equivalent) service,  microwave,
fiber links or other high-speed alternatives?

-- 
George Robbins - now working for,     uucp:   {uunet|pyramid|rutgers}!cbmvax!grr
but no way officially representing:   domain: grr@cbmvax.commodore.com
Commodore, Engineering Department     phone:  215-431-9349 (only by moonlite)