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Security and Alarm

3 Smart Laser Alarm Protection Circuits

Last Updated on January 2, 2024 by Swagatam 144 Comments

alarm

In this post I have explained the making of 3 simple yet effective smart laser alarm protection circuit using the IC 555, for securing a specified restricted zone from human interventions. The idea was requested by Mr. Collins. Circuit Objectives and Requirements 1) The Design Parts List IC 555Pinouts Circuit Operation The proposed smart yet […]

Filed Under: Security and Alarm Tagged With: Alarm, Circuits, Laser, Protection, Smart

Simplest Combination Lock Circuit Explained

Last Updated on January 2, 2024 by Swagatam 14 Comments

12V solenoid lock

A electronic combination lock is a device which is designed to activate an electrical solenoid locking system whenever the correct combination of numbers are entered into an attached keypad. To build this type of electronic combination lock, normally an electronic circuit with a keypad is used. In the design I have explained in this article, […]

Filed Under: Security and Alarm Tagged With: Combination, Explained, Lock, Simplest

Simple Water Heater Alarm Circuit

Last Updated on January 2, 2024 by Swagatam 1 Comment

buzzer with timer circuit

In this post I have explained a simple water heater alarm circuit which may be used as a safety device for getting indications regarding the switched position of a water heater or a geyser through intermittent buzzer actuation. The idea was requested by Mr. Mathew. Technical Specifications To be frank i am new to your […]

Filed Under: Security and Alarm Tagged With: Alarm, Heater, Simple, Water

AC 220V Over Current Monitor and Cut OFF Circuit

Last Updated on January 1, 2024 by Swagatam 12 Comments

220V load circuit breaker track side PCB

The proposed AC mains 220 V load over current cut off circuit continuously monitors the current flowing through a connected load. If this current increases beyond a certain preset level, the circuit trips the relay and disconnects the load from the AC. Basic Working This 220 V over current cut off circuit is indeed subject […]

Filed Under: Security and Alarm Tagged With: 220V, AC, Current, Monitor, OFF, Over

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

How Laser Microphones or Laser Bugs Work

Last Updated on November 25, 2023 by Swagatam 2 Comments

laser mic block diagram compressed

A laser microphone is a security monitoring gadget in which a laser beam is used for detecting audio vibrations across faraway targets, which are normally walls or glass of homes or offices. These devices could be applied for eavesdropping with virtually no chance of getting identified or cover getting blown. Laser eavesdropping gadgets, it is […]

Filed Under: Security and Alarm Tagged With: Bugs, Laser, Microphones, Work

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