A personal FM transmitter is a low-power FM radio transmitter that broadcasts a signal from a portable audio device (such as an MP3 player) to a standard FM radio. Most of these transmitters plug into the device's headphone jack and then broadcast the signal over an FM broadcast band frequency, so that it can be picked up by any nearby radio.
A personal FM transmitter is a compact device that emits audio from a portable source (such as an MP3 player) via FM waves. It typically connects to the device’s headphone port and broadcasts on an FM band, enabling any nearby radio to receive the signal.