In this post I have explained 5 useful power supply failure indicator circuits which can be used to get an instant indication regarding an input power failure situation. This post includes the following 5 types power failure indicator circuits: Main Function The main function of the proposed power failure indicator circuits is to alert or […]
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9 Useful LDR Circuits Explained
In this post I have explained 9 LDR circuit projects that uses LDR light sensor to trigger a load ON/OFF through a relay. These circuits are mostly triggered by the absence or the presence of light on the LDR. The circuits are built using transistors, op amps and LDR along with a switching relay. Let’s […]
3 Useful Electronic Mosquito Repellent Circuits Explored
In this post I have explained the construction of 3 simple electronic high frequency mosquito repellent circuits, which are specially designed to drive away mosquitoes through their tuned high frequency pulses. Design#1: Using a Single CMOS IC Mosquitoes are definitely a nuisance for your summer nights, especially when humidity prevails. Electronic mosquito repellent techniques can […]
3 Useful Temperature Alarm Circuits Explained
In this post I have explained the working of 3 interesting and useful temperature alarm circuits through detailed circuit diagrams. A temperature alarm circuit is basically a device which is designed to detect a temperature threshold and sound an alarm as soon the temperature exceeds over, or drops below the desired temperature detection threshold. 1) […]
6 Useful Voltage Controlled Oscillator Circuit Explored
In this post I have explained how to build 6 useful voltage controlled oscillator circuits, using various op amps and integrated circuits. As the name suggests, a voltage controlled oscillator or a VCO circuit is an oscillator circuit whose output frequency can be controlled or varied through an adjustable control voltage input. This means, if […]




