A transmission path between two terminal stations for transmitting digital information signals at a predetermined rate in one direction via a forward path and in the other direction via a return path. The transmission path comprises regenerative repeaters. A system for tele-location of these repeaters...http://www.google.com.au/patents/US4425662?utm_source=gb-gplus-sharePatent US4425662 - System for tele-locating regenerative repeaters
