1.5 Watt 1-2 km Range FM Transmitter

Here is a well designed FM transmitter circuit that works effectively in 1 – 2 km range.

Input source is an electret condenser microphone and signal gain can be adjusted by using the potentiometer P1. You can easily prepare the PCB by using any PCB editor and apply it to the board by using the ironing method. The coils and the antenna can be designed as a part of the PCB made up of the copper area.

 
R1=220K
R2=4.7K
R3,R4=10K
R5=100ohm
C1,C2=4.7uF Electrolytic
C3,C4=1nF
C5=2-15pF
C6=3.3pF
Q1=BC547C
Q2=2N2219A
P1=25K
MIC=Electret Condenser Type