So, I think the problem reduces to 'how to
interconnect RS232
ports'. let me add some constraints :
Must work over a distance longer than the RS232 spec allows (i.e. the
answer is probably not 'A long RS232 cable' :-)).
Prefereably no cables at all. One solution I've
come up with is to use a
couple of line drivers and a long cable between them. A long cable that
my parents, or the cat, will get tangled up in :-(
It were me, I'd probably look into Bluetooth- or Zigbee-based serial
extenders.
Disclaimer: I don't know what the regulatory issues might be with those
devices in the UK.
While this doesn't meeet your usual criteria for being able to repair
the device, it might be viable for you on the theory that the devices
are relatively inexpensive and could be treated as an interim solution
-- somewhat disposable, replaceable with a long cable if necessary, etc.
Presumably there'll be some new toy with the same function in a couple
of years.
In the long cable division, there are a number of products around that
extend rs232 by using baluns at each end, and cat-5 cable for the bulk
of the run. Still commits bondage on the cat :), but works around the
rs232 distance limitations. These I suspect you could reverse engineer
and build yourself.
I've also seen serial-to-ethernet devices. These plus a pair of wifi
access points...but we're getting expensive now.
De