This circuit is a FM transmitter. can run it by 9v battery. the power consumption is very low about 10mA so a small 9v battery worked for long time.
The frequency of radio must set between 88 to 93 MHz.
The circuit contain trimmer for set frequency of transmitter.
Part list:
Transistor BC547(2pcs)
Capacitor 10uF(2pcs)
Capacitor 1nF(2pcs)
Capacitor 5.6pF
Trimmer 2-18pF
Electret microphone
Part list:
Transistor BC547(2pcs)
Capacitor 10uF(2pcs)
Capacitor 1nF(2pcs)
Capacitor 5.6pF
Trimmer 2-18pF
Electret microphone
Resistor 4.7k(3pcs)
Resistor 100k
Resistor 10k
Resistor 270 ohm
Coil 4mm diameter 5 turns air-core (2pcs)
Antenna 10cm
Resistor 100k
Resistor 10k
Resistor 270 ohm
Coil 4mm diameter 5 turns air-core (2pcs)
Antenna 10cm
