I realise that incorrect antenna and less than ideal conditions will result in reduced range, but 1000m down to 0.1m? that's a 10,000 fold drop in range. I've tried 1/2 wave antenna on transmitter and receiver and tried a 1/2 wave dipole on the transmitter - note these are all made with cat5. I've turned off all the fluroescent lights to try minimise chance of stray noise in the workshop. Would a factory built aerial make this much difference and maybe give me 100m in less than ideal circumstances? Haven't yet tried a proper ground plane - any suggestios on size? Anything else you suggest I try? Surely LINX wouldn't be selling these modules if they can barely transmit over 0.1m