The Sounds of Ham Radio

George N2APB

Hey TLARCers-


Here is a way cool web page:   It’s a 10-band audio equalization filter, in which all modes of communication are ‘hidden’ in the audio stream that you hear – just drag up/down the respective control to hear the specific data being transmitted.  Quite amazing!


73, George N2APB


PS:  Thanks to David KF4DKW for spotting this gem.



Gaspar EA6AMM offers us a tour of the different signals picked up by his antennas. We can get a closer look at how HAM radio functions through his recordings.




At the core of this process, a carrier frequency is paired with a modulation that alters the carrier to convey data. The modulation can be either in the time domain, modifying the carrier’s presence at any given moment, or in the frequency domain, modifying the carrier frequency itself. The Morse modulation, for example, breaks the carrier into short and long bursts to encode the different letters of the alphabet. Thus, the carrier is modulated in the time domain. Frequency-shift keying, as illustrated by the third (orange) slider, doesn’t chop the signal as one might think. The carrier is always present, but switches between two frequencies. Thus, this is frequency modulation. The second slider (red) uses the same principle though at a much slower modulation speed and with more than two frequencies. This allows the slider to create something of a melody, albeit one born from an algorithm rather than a traditional music scale.


The fifth (green) and sixth (teal) sliders showcase contests for radio amateurs. Using Morse or plain speech, members of the HAM radio community had to contact as many contestants as fast as possible. In one of the latest world contests, our friend Gaspar was in 22nd position, with 4,700 contacts in 24 hours!


Many sliders in this generator create odd sounds. The seventh slider (light blue), for example, could be the soundtrack of a 1950s horror film. Behind these oddities, people who suffer from tinnitus may find a surprising relief. And those without can take advantage of the excellent noise-blocking properties of all these sounds.


If you like these sounds, consider joining the HAM radio community and meet cool people all around the world. After all, it was a real pleasure to team up with Gaspar.