[iTRIXX] Long live the long waves!

Join me on a dive into the depths of the radio spectrum.

Our WiFi networks run at 2.4 GHz, our FM stations operate between 80 and 108 MHz, and our shortwave and medium-wave transmitters take us even farther down the scale. Some antiquated radios still have a long-wave scale, and in the old days you could find a couple of stations there, but that's all past history now.

However, it's not the end of the story for radio frequencies. You can go even lower. Submarines use extremely low frequencies for communicating while submerged. Luckily, you don't need a submarine to do some experiments for yourself. All you need is a computer with a sound card (who doesn't have one?), some downloadable software, and a long wire to act as an antenna.

The software is called Speclab, and it can be found at the link below. This site also has some useful information about receiving ultra-long waves. Just install the software, connect a long wire (try 30 metres or more) to the sound card as an antenna, and get started. Speclab is a very extensive program, too extensive to elaborate on here. It turns your screen into a colourful waterfall of frequencies and signal strengths, and it has dozens of settings to play with. Give it a go – it's completely harmless. If you get hooked, check the web for "Lowfers". These guys are singing electromagnetic audio, it seems.

The world of long waves is a lot of fun, but can be a little confusing at times. We can generate and use radio signals from long wave to ultra shortwave, but ultra-long waves are also generated by nature causes, such as earthquakes, tornados and atmospheric disturbances. Some enthusiasts like to call it "Radio Earth". You can have a look at the 50-Hz and 60-Hz region on your screen to see the signals emitted by the power grid. There are also some other signals with less obvious sources – I should check them out some time.

Our question about the Golden Mean in electronics has received some feedback, but not yet enough to report. We'll take a rain check on that..

Wisse Hattinga