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Security and Alarm

Gadgets to Protect Women from Assaults and Harassment

Last Updated on June 16, 2022 by Swagatam 8 Comments

high voltage module

Gadgets and devices that are specially designed to repel or deter a potential male offensive can be used by a girl to protect herself from a crime situation, and therefore can be very handy. In this post I have explained a few of these devices which could be either purchased or even developed at home. […]

Filed Under: Security and Alarm Tagged With: Assaults, Gadgets, Harassment, Protect, Women

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

Simple Anti-Theft Alarm Circuit to Protect Valuable Items

Last Updated on May 24, 2022 by Swagatam 9 Comments

movement alarm circuit compressed

This easy yet useful security alarm circuit is designed to get triggered in response to even a brief movement of the unit, causing a loud alarm sound to set off. The circuit could be attached or installed on any desired gadget or asset which needs to be protected from theft. As soon as the gadget […]

Filed Under: Security and Alarm Tagged With: Alarm, Anti, Protect, Simple, Theft, Valuable

DIY Taser Gun Circuit – Stun Gun Circuit

Last Updated on March 23, 2022 by Swagatam 55 Comments

A Taser circuit also known as Stun Gun circuit is one non-lethal electric shock producing unit used to paralyze a person for a time being without causing any severe damage or injury. It is a very useful device, especially to immobilize an attacker. Using and making of stun gun is restricted in most of the […]

Filed Under: Security and Alarm Tagged With: DIY, Stun, Taser

Password Lock Circuit Using IC 4017

Last Updated on January 5, 2022 by Swagatam 27 Comments

4017 based password lock circuit

In this post I will show how to construct a general purpose password based electronic lock circuit without any involvement of microcontroller. You can use this circuit for numerous applications where a basic level of security is required for turning a circuit ON. The proposed project is built using an IC 4017 and the circuit […]

Filed Under: Security and Alarm Tagged With: 4017, Lock, Password

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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