I have just publised a video that shows you how to convert any solenoid valve into a smart innigation controller. Variations in the irrigation frequency are controlled by the prevailing weather conditions, namely, rainfall and evaporation.
Key features
Unpowered (no batteries, no solar panels, no computers, no electronics)
Use for sprinkler or drip irrigation
Adjust the water usage by adjusting the control dripper
Adjust the irrigation frequency by changing the evaporator
Water usage is independent of the water supply pressure
Uses much less water without affecting the yield
You can leave your irrigation application unattended for months on end
Use for any size irrigation application by using a sufficiently large solenoid valve
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