so difficult to answer ... depends on the transmitter AND the receiver, what's between the two devices, modutation and error check, etc
guess about 100 meters, just an order of magnitude
i wonder how come the batterry of the AM transmitter kit that i bought from Microchip drain out so fast. i think it only takes a week or more to drain it. so does it mean tat this rfPIC12F675 IC consume alot of power? anyone faces the same problem? or got better idea to solve this battery hungry circuit? thanks