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I know it's not very practical for most people, but there are still huge advantages to using Morse code (aka CW - continuous or carrier wave) for emergency communication.

The transmitting...

Just seen this:

https://scontent-frt3-1.xx.fbcdn.net/hphotos-xfl1/v/t1.0-9/12994515_10208182348669579_3172768576104254083_n.jpg?oh=da6f08088b2b7e0e93ef1c46259d7ccf&oe=57B55A35

A classic example...