A simple infrared wireless alarm circuit can be built using an 433 MHz RF remote control unit a TSOP based IR sensor, I have explained the procedures in detail. In a few of the other posts I have discussed regarding these RF remote control modules. For more info you may go through the following relevant […]
Alarm
Simple Ultrasonic Sound Sensor Alarm Circuit using Opamp
This article discusses a simple ultrasonic sound sensor alarm circuit which may be appropriately set for detecting sound pressures well above the normal human listening capacity, that may range from 20 kHz and over. Ultrasonic Concept Ultrasound or ultrasonic sound waves was probably invented even before humans existed on this planet by a few of […]
How to Make a GHz Microwave Radar Security Alarm Circuit
In this post I have explained a GHz microwave radar security alarm circuit which is designed to detect an intruder within the critical zone only while it’s moving, static objects produce no effect for the sensor. Using Doppler Sensor KMY24 In the previous article I have explained about a microwave Doppler radar sensor module KMY […]
LPG Gas Leakage Detector Alarm Circuit
Are you feeling vulnerable or suspecting a possible LPG gas leakage in your house? Then may be this gas leakage alarm circuit might help you. Written by: Sai Srinivas The Concept This circuit is a simple solution for detecting LPG gas leakage in households which causes severe physical and monetary losses if left unattended for […]
Power Interruption Alarm Circuit for Instant Power Failure Indications
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 […]
Simple Shadow Sensor Alarm Circuit
This shadow detector circuit operates using two LDRs and effectively detects the difference between the light levels and triggers a loud audible warning siren. In circuits which uses a single LDR (photoresist), the detection may not be as sharp as with two LDRs discussed here.Operational details of the shadow detector circuit may be studied as […]