Extending USB over Cat5

[Tim Hawes <timsyahoo@xxxxxxxxxxxxxx>]

I've got an RF keyboard (CPC p/n CS11987) that I want to use in the
lounge with the PC upstairs in my new wiring closet. Different bits of
documentation state ranges of 3, 4 & 5m although what I actually get
is closer to 1.5m :-(
I've got enough Cat5 installed to be able to move the receiver closer
or even down into the lounge but I'm puzzled how to extend it. There's
a few suggestions on the web but has anyone here actually done it? I'd
prefer a DIY solution before splashing out =A330 on pre-made adaptors.
Any suggestions on what colour code to use and whether I should put
the data +/- on the same cat5 pair and whether to use a single pair
for 5V & 0V or use a pair for each?

Total Cat5 length will be in the region of 10-12m.

Alternatively, what options do I have for focussing the RF signal
better? It's a 40 MHz system.

Thanks,

Tim.

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