But for a weekend project, [Vinod.S] took the ultrasonic transmitter and receiver from a distance ... Due to the low 40 kHz carrier frequency, the sound lacks the higher audio frequencies.

Is your ham radio rig made of iron and ... Most of the challenge in receiving the Alexanderson transmitter broadcasts are due to this very low broadcast frequency; your antenna is not long enough.

By allowing the receiver on Earth to generate two of the three light frequencies needed for noise-free amplification, and at the same time allowing the transmitter to generate only one frequency ...

Other Ways to Send Audio From Your Phone to Your Car FM transmitter apps ... On the other hand, FM radio apps may work even ...

Dyer firefighters are training in the use of radio receivers to locate at-risk individuals with ankle-worn FM transmitters.