The transmission frequency of the audio transmitter module can be adjusted, and the adjustable range covers 88‑108mhz national standard FM band.
With 0.7V‑9V wide voltage working range, long transmission distance, strong practicability.
You can use radios and mobile phones as receivers (the earphone cable for mobile phones makes the antenna sensitivity very poor and is not recommended).
The green component is a tunable capacitor, changing the tunable capacitor can change the transmit frequency.
Widely used in sound transmission pickups, audio microphones, sleep monitoring and other situations where sound needs to be captured.