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Security and Protection

Voice Recorder and Playback Circuit

Last updated on 13 May 2026 by Admin-Lavi Leave a Comment

Does anyone get tired of buying expensive voice recorders? then this Voice Recorder and Playback Circuit show how to make easy one at home! Also, we can use it to record small message for family or friend, by just pressing two button one for record and other one to listen. Note: This project is little […]

Filed Under: Audio Circuits, Automation Circuits, DIY Projects, Security and Protection

Self Discharge Battery Protection Circuit

Last updated on 12 May 2026 by Admin-Lavi Leave a Comment

This article for Self Discharge Battery Protection Circuit teaches how to make one easy circuit to protect car battery (lead acid type) when not using. Also, this circuit help battery live more long time and keeps it healthy. WARNING: Making lead battery for car can be dangerous, so try to do this with one big […]

Filed Under: Battery Charger Circuits, Power Supply Circuits, Security and Protection

Simple DC Over Voltage Protector Circuit

Last updated on 9 May 2026 by Admin-Lavi Leave a Comment

To begin with, main purpose of Simple DC Over Voltage Protector Circuit is to save electronic parts or circuits from damage when voltage from DC power source become too high. Also, this type of circuit works very well in many applications that need stable and fixed voltage. Circuit Working: Parts List: Components Values Quantity Variable […]

Filed Under: Mini Projects, Security and Protection

220V Over Under Voltage Cut Off Circuit using Transistors

Last updated on 9 May 2026 by Admin-Lavi Leave a Comment

This 220V Over Under Voltage Cut Off Circuit using Transistors help to protect electric things from too high or too low voltage, it also uses two transistors and some easy parts. First, when voltage goes too much high or too much low then circuit cuts the power, also it is good for home use and […]

Filed Under: High Voltage, Power Supply Circuits, Security and Protection, Transistor Circuits

Simple Lie Detector Circuit using Transistors

Last updated on 8 May 2026 by Admin-Lavi Leave a Comment

Have fun making this Simple Lie Detector Circuit using Transistors. Real lie detectors are very hard and complicated so this one is not perfect; but it is fun way to see how body react when its in stress. Also, this circuit works by detecting changes in sweat to check whether someone may be telling the […]

Filed Under: Hobby Circuits, Mini Projects, Security and Protection, Sensors and Detectors, Transistor Circuits

Simple Metal Detector Circuit

Last updated on 7 May 2026 by Admin-Lavi Leave a Comment

This article show a special trick to make a Simple Metal Detector Circuit, which uses simple circuit not like other circuits and needs only one transistor. The circuit find metal by catching signal from a normal radio. What is a Metal Detector: A metal detector is an electric circuit that checks whether metal is nearby, […]

Filed Under: DIY Projects, Hobby Circuits, Mini Projects, Security and Protection, Sensors and Detectors

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