it was a very configurable transmodulator, taking satellite digital signals in at one end. Stripping the multiplex down into its component parts, assembling a new multiplex from those parts and re-modulating it as a digital cable signal. A sort of mini head end. It also allowed high speed data connections between the cable end and the box thus acting as an internet gate way, and multi-channel satellite system over poor quality coax lines that were already installed in buildings as communal antenna systems.
You know that was my first though when looked at the photo 
BTW I love those head magnifiers gadgets, the combination of older eyes and smaller components is not good but they save the day. I've got one with lights that illuminate the subject as well.
Rob