800 EMI and ESD - k3ng/k3ng_rotator_controller GitHub Wiki

When planning a rotor system based on the Arduino processor the designer should be aware that the Arduinos and their attendant shields were intended for physically small systems, like a robot or a CW keyer.

In contrast an antenna rotor is a large distributed system with unique challenges relating to moving digital data hundreds of feet in an electrical environment that is unforgiving.

Things to consider:

• Clocked ICs radiating into the antenna.
• High RF fields getting into the IC inputs.
• External fields, such as generated by nearby lightning, destroying IC inputs.
• Electrical pickup by long conductors in the near field of the antenna.
• Magnetic and electrical radiation from brushed DC motors.
• SPI and I2C signals were not intended to be used for distances of more than a few feet.

The required interface ICs and associated EMI suppression can easily become more complex than the Arduino modules.

As a minimum all electronics should be enclosed by metal with shielded cable between units.