Amateur or “ham” radio is a method of two-way communication. At first glance, it resembles Citizen’s Band (CB) radio or perhaps walkie-talkies, but there is much more to it. Amateur radio has more capabilities beyond what is possible with a walkie talkie or CB radio.
Besides local communication, as is possible with a CB radio, amateur radio can be used to bounce signals off layers of the ionosphere, a layer of the Earth’s atmosphere with free electrons and ions due to incoming solar radiation. Because this layer is high above the Earth’s surface, these reflective layers can be used to bounce signals long distances, making amateur radio a world-wide communication method.
Communication modes
Unlike CB, amateur radio also allows for multiple communication modes: generally grouped into voice modes, continuous wave (CW) or digital modes.
Voice modes are probably the most obvious; each operator speaks into a microphone. However, inside of voice modes are Amplitude Modulation (AM), Frequency Modulation (FM) and Single Side Band (SSB), all of which take the operator’s voice, mix in a high frequency and send the signal to an operator elsewhere. The operator’s radio then removes the high frequency, and the audio will come through their speaker.
CW is a method of sending Morse Code. Morse Code is simply the agreed upon sets of “dits” and “dahs” used to make letters and words, and CW is an on/off switch to an oscillator that sends tones when switched on. In other words, CW is the original digital mode, “on” sends a tone and “off” sends nothing. CW is still very popular, as it tends to be more audible through noise.
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