[Reza’s] methodical investigation of this remote controlled outlet let him patch in with an Arduino using a 433 MHz transmitter. This is a single-device unit, but the techniques used here sho… ...

The statement analogWrite (3,i); is how PWM is implemented in the Arduino. Pin 3 will output a square wave with a certain duty cycle. A value of 0 means a duty cycle of 0%, or completely off.

A Raspberry Pi Zero Shield that will connect a Zero or Zero W module to a 3.3V or 5V compatible Arduino board, is available from US-based Burgessworld Custom Electronics. The two boards are connected ...