Hai friends..i am willing to post my experience here.i was using my r/c s ranges from 18 MHz, to 79 MHz.most of the r/c systems i use are home made, using RX and TX ICs.most of the toy r/c s based around 27 MHz to 49 MHz. so whatever may be the frequency i always add a 5 meter wire in between two coconut trees with an insulator at each end.so it ill give me a range about 1.4 Km from 27 to 49 MHz.for airplanes i use a steel wire lengths over 3 meters on a wooden reaper pole,with vertical polarisation.but i always get enough range with Ghz transmiters.if you want to increase the reception range of your receiver you can simply add a reception booster at the tip of your receiver antenna.its so simple can make on a plastic card, with one transistor, and a tuning circuit, mostly based on C1815, or C 945 transistor.so it will grab any week frequencies passes nearby..cool..