A small box with indicator lights attached to a yellow cable.

Photograph by Matthew Millman*, 2012 – image used with permission

Cabletron 10BASE5 Ethernet transceiver with AMP vampire tap

This “Thick Ethernet” transceiver is identical to the devices we used to build our first Ethernet (with two hosts) at the Department of Computer Science. The diameter of the stiff yellow coaxial cable is 9.5 mm, it can transfer max 10 Mbit/s, and can theoretically be 500 m long. Hence the name 10BASE5.