Here is a tested Arduino project that uses 3 sensor probes as water level indicator with 3 leds and one LCD display + a simple controller that turns on a motor when the water has reached the desired ...

This is a simple arduino project for a soil moisture sensor that will light up a LED at a certain moisture level. It uses Arduino Duemilanove microcontroller board. Two wires placed in the soil pot ...

Although simple in theory – an air bubble and conductive liquid sealed in a chamber surrounded by electrodes – electronic levels are more complex in practice. If the liquid is an electrolyte, it needs ...