Arduino automatic CQ caller for amateur radio

VK3YE likes to work CW (Morse Code) on the 40-meter band, but doesn’t like the monotony of hand keying CQ endlessly. He devised this simple project using an Arduino to tap out CQ and his call sign automatically at predetermined intervals. The keying was originally accomplished using a reed relay as shown in the video. However, after several days of use it became sticky. So he switched to the circuit described in snarfusmaximus’ video below, consisting of a 4N25 optocoupler and 470 ohm resistor.

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    1. CW means Continuous Wave. I think the CW for Morse Code is correct. CQ I believe is followed by the operators specific identifier. I don’t know why it’s sent out at intervals, not being a ham operator.

  1. To clarify. CW stands for continuous wave, the on-off keying of a radio carrier in a pattern corresponding to what we refer to as Morse Code. The abbreviation CQ is an on-air abbreviation used in both voice and CW modes which is an invitation for any operators listening on that frequency to respond. It is sent repeatedly along with the station’s call sign in the hope of establishing contact with a listening station.

    1. Thanks for clarifying that machinegeek! With Q and W being next door to each other, I figured it was a typo. Oops. :)

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