Arduino CW Beacon
Channel: Michael Williamson
Date: 2015-09-29

Using an Arduino as a true CW beacon controller.  The data pin (13) on the Arduino is connected through a 220 ohm resistor to the base of an NPN transistor.  The collector the NPN connects to the radio's CW port, and the emitter to the ground.  Both the radio ground and Arduino grounds are connected.  This transistor configuration allows the arduino's HIGH state to pull the radio CW port to ground, which activates it.

The arduino generates no audio in this configuration, simply +5 volts on pin 13 for on, 0 volts on it for off.