I have built a remote control car, pwm speed controll and all, using picaxe microcontrollers and gained a lot of experience doing it. I used a low power i think 20mw transmitter you can find all over ebay that uses a 433hz carrier wave. A long time ago i found a 1w transmitter meant to be a step up from the common 20mw i mensioned but if i do not want to use the larger 1W transmitter, then will 2 20mw transmitters double my range? It may seem like an obvious question but i lack in knowledge reguarding electrmoagnetic waves and such. Or will even using 2 recievers increase this sensitivity?