AM Ultrasonic Transmitter And Receiver
Most often ultrasonic transducers are used for distance measurements, and in the DIY world, usually as a way for robots to detect obstacles. But for a weekend project, [Vinod.S] took the ultrasonic transmitter and receiver from a distance-meter module and used amplitude modulation to send music ultrasonically from his laptop to a speaker, essentially transmitting and receiving silent, modulated sounds waves.
For the transmitter, he turned an Arduino Pro Micro into a USB sound card which he could plug into his laptop. That outputs both the audio signal and a 40 kHz carrier signal, implemented using the Arduino’s Timer1. Those …read more
