Acorn Econet test Box (top)
Acorn Econet Test Box (open)
This is obviously a device for testing an Econet, but I have no documentation on it so I don't know exactly what it does.
There are 2 Econet sockets on the front, one marked Tester, the other marked UUT (unit under test), and a ribbon cable connector presumably to connect to a BBC Micro user port. The red and black wires are connected to a socket which will plug into the disc drive power socket underneath a BBC micro..