In this post I have explained how to use IC 555 to create 7 interesting siren and alarm sound effect generator circuits. The versatile astable multivbrator configuration of IC 555 allows us to implement it for making various types of sirens and alarm circuits. This becomes possible because an astable is basically a waveform generator, […]
Security and Alarm
Laser Activated GSM Call Alert Security Circuit
In this post I have explained a simple laser GSM call alert security circuit which immediately calls the master as soon as an intruder is detected through a laser beam interruption. The idea was requested by Mr. Roldan. Circuit Objectives and Requirements I am not an electronic engineer, but I can manage to troubleshoot minor […]
Security Alarm Circuit using RCWL-0516 Microwave Radar Sensor
This security alarm circuit using RCWL-0516 microwave radar motion sensor will detect any moving thing in the restricted area and turn ON an alarm sound. The RCWL-0516 is basically an advanced motion sensor using microwave radar signals. I have already discussed the working of RCWL-0516 elaborately, which you can read for more details. Circuit Description The […]
Flashlight Activated Burglar Alarm Circuit
This flashlight triggered burglar alarm circuit will instantly switch ON an alarm as soon as it detects light from the burglar’s torch or flashlight. Burglars and thieves normally set out to steal or rob during nights, when it is completely dark, and depend on a flashlight to investigate the area. Our circuit is setup and […]
Mobile Phone Controlled Door Lock Circuit
Controlling your door lock through your personal cell phone was never this easy. Learn how to build a simple electronic circuit that will help in converting your ordinary door lock into a high security door lock which can be now controlled through your own cell phone. Your ordinary door lock can be now very easily […]
Infrared Remote Control Safe Lock Circuit
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 […]





