An electronic, microprocessor-based controller was developed
and tested for automating surface irrigation systems. Communication
between the central controller and individual satellite field stations
is by tone telemetry over a single 3-conductor wire. The reliable Dual
Tone Multiple Frequency or Touch Tone system is the same as that used in
telephone communications. The system is designed to actuate momentarily
energized pilot valves commonly used in automated surface irrigation
systems. Because of its low power requirement, the control system can
be battery-powered. It is being field tested in three different, automated
surface systems