What is this loft spider?

Venturing into the loft of a very very old house, a pal of mine found this odd spider.

Ok, it’s not a spider, but I thought I’d throw this open to you, dear readers, for between you there is a wealth of knowledge.  Now, my thinking is that this is some kind of aerial.   But for what?

Firstly, the beam has a rusting, but nicely fashioned sticky out holder thing. Obviously this was purpose built. Then there’s the rather amateurishly cut spray of lengths of cable.  They appear to be going into a piece of old porcelain insulator at the end of the rusting but nicely fashioned sticky out holder thing.

And then, from this contraption there goes away a feeder type cable.  It is strung around the loft in a rather haphazard fashion, but cut off from wherever it may have gone to downstairs.

So.  What is/was it?