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Security and Alarm

Ultrasonic Weapon (USW) Circuit

Last Updated on June 2, 2022 by Swagatam 103 Comments

ultrasonicdefender

In this post I have explained a simple ultrasonic weapon circuit also called USW, using very ordinary parts such as IC 555 and a few other passive components to generate the required ultrasonic ear piercing sound. Controlling Crime with USW With rising crime in today’s society, especially against woman, carrying some sort of effective weapon […]

Filed Under: Security and Alarm Tagged With: Ultrasonic, USW, Weapon

Laser Diode Driver Circuit

Last Updated on October 16, 2020 by Swagatam 40 Comments

ddl laser driver and current and voltage measuring circiut 001

The current controlled circuit of a laser pointer power supply explained in the following post was requested by Mr. Steven Chiverton (stevenchiverton@hotmail.com), who himself is an intense electronic hobbyist and researcher. Technical Specifications Dear swagatam, I’m emailing you to ask you for your expertise, and you being one of India’s finest electronics engineers I thought you be […]

Filed Under: Security and Alarm Tagged With: Diode, Driver, Laser

5 Simple Alarm Circuits for Protecting your Home/Office from Theft

Last Updated on January 2, 2024 by Swagatam 104 Comments

burglaralarmusingsimpleconductorsensorcircuit

The following article discusses a few very simple intrusion detector circuits, or ant-theft alarms. The presented designs are easy to build yet extremely effective with the functions. How the Circuits Works An intruder alarm basically consists of a sensor and a trigger stages, which work together to produce the required detection. The sensor detects the presence […]

Filed Under: Security and Alarm Tagged With: Alarm, Circuits, Home, Office, Protecting, Simple

Make this Solar Powered Fence Charger Circuit

Last Updated on March 15, 2020 by Swagatam 149 Comments

enhanced two wheeler ignition circuit

A Fence charger or energizer is an equipment which is used for charging(electrifying) a fence or a boundary in order to protect the inside premise from human or animal interventions. Since these boundaries are mostly of large fields and parks, are normally away from the main cities, and powering them through some renewable option becomes […]

Filed Under: Security and Alarm Tagged With: Charger, Fence, Powered, Solar

2 Tone Ringtone Generator Circuit

Last Updated on January 19, 2025 by Swagatam 4 Comments

twotonealarmcircuitwithspeaker

The IC LS1240A from SGS Thompson is specifically designed for generating a 2 tone ringtone generator circuit. Thus the IC specifically becomes suitable for landline telephones for producing the ringtones when a call is received. However with little modifications the IC can be easily utilized for normal applications, in circuits where a double tone alarm […]

Filed Under: Security and Alarm Tagged With: Generator, Ringtone, Tone

Earthquake Sensor Circuit [Seismic Sensor]

Last Updated on September 30, 2021 by Swagatam 43 Comments

earthquakesensorcircuitsiesmicsensorcircuit

The article shows an earthquake sensor circuit idea which incorporates an innovative way of detecting the minutest of shocks caused by a possible earthquake tremor. The circuit is so sensitive that it is able to detect tremor of 4 on the Richter scale, yet remains unaffected to loud sounds or irrelevant bangs or noises. Introduction […]

Filed Under: Security and Alarm Tagged With: Earthquake, Seismic, Sensor

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