Simple, Easy to Build FM Voice Transmitter Circuit
An easy and simple to build FM (Voice) transmitter circuit that operates in the 88 to 108 FM band, or into the
VHF band, if the turns on the inductor are decreased.
The 4.7 to 22 pf trimmer capacitor in conjunction with the 0.26 uH inductor (Estimated)
allows the frequency to be adjustable in the 88 to 108 MHz band..
The inductor can be 5 or 6 close wound turns of # 18 Magnet wire, air wound around a 3/8
inch drill bit. Output power can be increased by decreasing R4. The antenna is a piece of
small wire, or flex wire around 18 to 20 inches. For operation into the VHF 147 to 174 MHz
range simply decrease the turns of the inductor.