I've been playing with two Arduino and two transmitter/receiver pairs, one at 433Mhz the other at 315Mhz. These modules are VERY cheap, which is fine since I am only learning/experimenting.
I've used VirtualWire to get the two Arduino successfully talking to one another but the range is terrible, maybe a few centimeters at most. I've tried a range of different antenna lengths (just a straight piece of wire) based on various bits of information I've managed to find through Google and searches on these forums but it doesn't appear to make a great deal of difference.
I just wondered if anyone had any clues on what's happening. Is it possible the two pairs are interfering with each other? If I use just one transmitter/receiver the range is better...sometimes with a stable two way connection over a few meters and/or between rooms. Maybe it's because the modules are cheap?
Any advise appreciated.