Simple MP3 FM transmitter

Simple MP3 FM transmitter

This demonstrates a simple MP3 FM transmitter circuit that can be easily built in minutes if all parts are available. All components used in this transmitter circuit are universal and low-cost. This circuit will serve as an ideal FM transmitter for simply broadcasting your music around your house and yard, and can also be used to broadcast the output of any device such as an MP3 player, iPod, satellite, etc.

Coil L1 consists of 8 to 10 turns of 22 gauge wire wound on a 6mm bobbin. After winding, the bobbin is removed. Next to the coil is a 1-30 pF trimmer capacitor used to adjust the frequency of this MP3 FM transmitter.

After building the circuit, apply power and connect it to the device's audio output. Then, set a blank frequency on an FM radio and gently adjust the transmitter's tuner with a non-conductive tool until you find the sound of your music. The minimum antenna length should be 12 inches, but you can increase the antenna length to 30 inches if you want to increase the range. You can power this FM transmitter circuit with any size/type of 1.5V or 3V battery.