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Security and Alarm

Infrared Remote Control Safe Lock Circuit

Last Updated on January 8, 2024 by Swagatam 19 Comments

motorcyclesecuritytransmittercircuit

A simple, cheap yet highly effective infrared remote control safe lock circuit can be studied in the following post. Using IC LM567 The LM567 IC is one of my favorites simply because it’s too versatile, and becomes applicable in most of the crucial circuit concepts through hassle free configurations. One such crucial yet simple IR […]

Filed Under: Remote Control Circuits, Security and Alarm Tagged With: Control, Infrared, Lock, Remote, Safe

Power Interruption Alarm Circuit for Instant Power Failure Indications

Last Updated on December 21, 2023 by Swagatam 17 Comments

This power interruption alarm circuit will alert you whenever there’s a power failure or an interruption in the mains. In some special conditions it becomes imperative to know whether the mains that powers some important system or circuit is absent. By: Manisha Patel How the power failure alarm works This proposed circuit is connected to […]

Filed Under: Security and Alarm Tagged With: Alarm, Failure, Indications, Instant, Interruption, Power

Make this Simple Refrigerator Door Open Alarm Circuit

Last Updated on January 3, 2024 by Swagatam 25 Comments

This presented refrigerator door open alarm circuit which alerts you after a period of time whenever your refrigerator door is left open. This circuit becomes very handy, because in case the door is left due to carelessness may cause significant increase in the consumption and affect the life of the fridge. Circuit Operation This circuit […]

Filed Under: Security and Alarm Tagged With: Alarm, Door, Open, Refrigerator, Simple

How to Make a Barcode Security Lock Circuit

Last Updated on January 3, 2024 by Swagatam 12 Comments

barcodescanner 2

A simple barcode security lock circuit or barcode scanner circuit is explained in the following article using just a handful of ordinary components such as an op amp, an LDR and an laser light. We all have seen and are familiar with these arrays of thick and thin lines which can be seen printed on […]

Filed Under: Security and Alarm Tagged With: Barcode, Lock, Security

Office Call Bell Network Circuit with LED Monitor

Last Updated on November 15, 2023 by Swagatam 2 Comments

officeroombellnetwork

In this post I have explained an office call bell network circuit for office complexes which could be used for calling and monitoring office member’s attendance and response from the particular intended office chamber. The idea was requested by Mr. Rajib Banerjee Technical Specifications Need a perfect useable circuit idea for Ringing the Bell as […]

Filed Under: Security and Alarm Tagged With: Bell, Call, LED, Monitor, Network, Office

Power Switch ON Alarm with Auto OFF Circuit

Last Updated on July 6, 2019 by Swagatam 17 Comments

In this post I have explained a simple monostable based power switch ON alarm circuit which automatically switches OFF after an adjustable preset delay. The idea was requested by Mr. Will Boswell. Technical Specifications Hi there, my name is Will Boswell. I am currently working on a project that involves adding an alarm sounder to […]

Filed Under: Security and Alarm Tagged With: Alarm, Auto, OFF, ON, Power, Switch

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