[R-390] Coax

[Flowertime01 at wmconnect.com]

Rick,

You visit the best old computer shop in town and ask for some IBM twinax for 
use in an IBM star or ring topology network. They may have a couple chunks 
laying around in the stash pile. You use the same twinax connectors.

You may look up the cable in a computer book and get 6 or 12 foot cable with 
a connector on both ends. That should be a life time supply. This will be IBM 
network cable. 
It has the connectors to mate with the R390 or R390/A  balanced input.
It may be called twinax or two conductor coax. It is about 3/8 OD like fat 
coax.

Roger.