DEC AUI Cable

AUI = Attachment Unit Interface (IIRC), the interface between an ethernet controller and the MAU (Media Access Unit). It's the cable for an ethernet tranceiver, therefore. At one time ethernet transceivers were not built into the computer/interface card. They were semi-permanently fixed to the coaxial cable. And you used an AUI cable to connect the computer to the transceiver. It's 4 twisted pairs. 3 are identical and carry the 3 transceiver signals (transmit data, receive data, collision detect). The other pair is thicker wires (officially) and carries the 12V power supply to the transceiver. A few years about I had to make up one of these cables because my PERQ uses 4-40 screw-down jackposts and not the normal slidelock posts on the ethernet connectors. Getting a couple of metres of the cable was the hardest part of the job! -tony