Usually light dependent resistors (LDR) and photodiodes are used as light sensors to activate or deactivate circuits based on the presence or absence of...
The overflow alert system presented here will electronically monitor cistern (tank that holds water to flush the toilet) overflows that can otherwise cause seepage...
Manual buzzers used for quiz competitions in schools and colleges create a lot of confusion in identifying the first respondent. Although there are circuits...
Over-watering and under-watering both are harmful for plants. Roots need air as well as water. If the soil is constantly saturated, air cannot reach...
This suitcase-lift alarm circuit uses vibration sensor HDX-2NC instead of a commercially available sensor. A home-made mercury switch can also be used instead.
Suitcase-lift alarm...
This thermistor based fire alarm project can effectively be used as a temperature-sensing fire alarm. Here, an NTC thermistor is used as the temperature...
This auto turn-off battery charger for series-connected 4-cell AA batteries automatically disconnects from mains to stop charging when the batteries are fully charged. It...
Here is a simple optoreflective sensor circuit based on TCRT5000 module. It is ideal for projects like robotics, position sensing, proximity sensing, detection of...
The electronic eye security systems available in the market are expensive, and programming is very difficult for a microcontroller based system. Here is a...
An optical smoke alarm (also called photo-electric smoke alarm) works using the light scatter principle. The alarm contains a pulsed Infra red LED which...