For those of you like / love to talk in the air can assemble this simple circuit that can be received by the radio receiver to within a few hundred feet. The voice that issues by this circuit at all clear without rustling. Can also be used to link communications over the air using this radio transmitter, provided that other person also had the same circuit.
This PCB design :
Q1__________________ Crystal according to the desired frequency
X2-2________________VCC 9-12 Volts DC