These ideas are identical to concepts used in cell phones and Wi-Fi. Initially we build a transmitter and receiver to communicate between Arduinos using Morse code sent by pulses of light waves. Next, ...

making them a great Arduino alternative if you can do without some of the bells and whistles. [ech0s] put his to good use by constructing a Morse code transmitter with dual operating modes.

It’s a Morse Code ... (locating a hidden transmitter using radio direction finding). For the project he revised his old code, adding in a Morse look-up table so that the Arduino Mega 2560 ...

How did we make our transmitter ... Morse key is a switch that connects and disconnects the 12V power to the rest of the circuit. It has a wooden knob on the top, which makes tapping out the Morse ...