Anyone know the range in feet or meters that x10 signals get sent out?
PLC or RF?
These are "WAGs" based on mostly personal experience, so FWIW.
Range will vary depending up many factors. A PLC signal in an X10 installation using a coupler/repeater will get stopped at the pole transformer. Several forum respondents are sending PLC to barns and sheds greater than 100 feet away. RF is also very dependent on outside factors, but the antennas on X10 transmitters are really very poor (probably by design) and without going to more sensitive receiving antennas or better receivers, I don't think an RF signal from a motion detector or Palm Pad is good for more than 50-60 feet. A good communications receiver and directional antenna could probably pick up an X10 remote transmission from hundreds of feet away, and a direction antenna properly coupled to a Palm Pad could probably transmit for a couple of hundred feet...but there ain't much point in doing that unless you just want to drive your X10 neighbor nuts.
Dave_X10 probably has accurate guesses for the wireless cameras range.