Moisture sensor circuit diagrams

Water-level Alert

Beeper or flashing LED alert 1.5V battery powered portable unit

Water-level Indicator

Simple, two-wire, remote monitoring unit Three-LED level display, 9V battery powered

Water Activated Relay

In his circuit Marin has used two transistors wired as a high gain compound pair.

Water Pump Relay Control

Water reservoir automatic level control. Simple circuitry - 12V supply

Plant Watering Watcher

A flashing LED signals the necessity to water a plant Very low current consumption - 3V powered circuit