Keyboard cables too short

[Doug Faunt]

We're running a SUN-2 monitor and keyboard at 70 feet using three sheilded
pairs in a cable, one for the keyboard and mouse and another for the
video.  The monitor and video board are ECL which was necessary for that
long a run, but the mouse and keyboard are TTL levels.  If you want to
build your own "amplifier" it'd just require a +5 volt supply at the
KB/mouse end and a non-inverting line driver IC.