The X10 audio/video RF receivers (VR30A,
VR31A) have a 75 Ohm RF modulator output with
a Type F connector. If your coax is also 75
Ohm you ought to be able to use it directly,
otherwise you'd _probably_ need an impedance
matcher.
This output is intended for a short cable
connection to a TV set - whether the signal
strength is high enough for very long cable
runs I can't say.
If you're considering one of the "cabled" X10
cameras, you'd need a 3rd-party video
modulator ($10-$20) and the same comments
about impedance matching and signal strength
would apply.
(My assuption in all the above is that the RF
range of the cameras is too short for you to
bypass the cable entirely.)
