Sensor Circuits

Power Supplies, Sensor Circuits

Mains failure alarm circuit

 Description. Here is a simple mains power failure alarm/detector circuit that produces an alarm whenever the mains supply fails. Lot of such circuits are available, but the peculiarity of this circuit is that it requires no back up power source like a battery to power the alarm when the mains is absent. When there is […]

Industrial Circuits, Sensor Circuits

Dew sensitive switch

Description. Here is a simple circuit that can be used to switch ON or OFF a device when the dew present in the surrounding atmosphere crosses a set value. The circuit uses a dew sensitive resistive element and a comparator based on LM 358 to perform the above said operation. At normal condition the resistance

Industrial Circuits, Sensor Circuits

Digital temperature sensor

Description. Here is a straight forward, yet effective digital temperature controller that can be used with temperature control systems. The circuit uses IC LM 35 (IC3) to as the temperature sensor. The output of LM 35 is given to the IC ADC 0804 (IC4) which converts the analog output of the LM 35 to digital

Metal detector circuit
Radio Circuits, Security & Saftey

Metal Detector Circuit

Metal Detector Circuit I always wanted to make a metal detector seeing how cool it was in all Hollywood, Bollywood movies. One thing I realised is; things aren’t as difficult as you think it is. After all, I found that a metal detector is really simple and easy to make. So in this post, I

Proximity Detectors

Simple Proximity Detector

In this project, let’s learn how to make a Simple Proximity Detector or Sensor circuit using minimal components. A proximity detector is a fun project with lots of interesting applications to be built with. You can make very useful applications like a burglar alarm, a visitor counter, a proximity-based switching application, etc. This is a

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