Why Learn Radio Guide
Cell phones have become our primary communication devices because of their versatility, portability and ease of use. However, the problem with relying on them too heavily is that during an emergency, the likelihood of them failing can become a big concern.
If we think about contingencies and recognize the limitations of the devices we rely on so heavily these days, what can we use to fill that gap if the cell networks become overloaded? Enter the venerable radio.
Radio Origin
Walkie-Talkies were rudimentary communication devices that were fairly poor in terms of quality, reception and range. This was due to being limited at 100 milliwatts (0.1 watts) of power and lacking good antennas. Most just had an on/off switch, but some even had the ability to tap out Morse Code. Your buddy who had a different model of walkie-talkie could still hear you through his, as long as you were close enough.
In North America, these Walkie-talkies operated on the 27 MHz citizens band using amplitude modulation (AM). It wasn’t until much later that walkie-talkies appeared using the 49 MHz band with frequency modulation (FM), much like the cordless phones of yesteryear.
With walkie-talkies, you were lucky if you could communicate within line-of-sight down the street, let alone burn through fences.
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