This circuit will raise an audible alarm as soon as the battery voltage goes above a predetermined over voltage limit. The astable section of a high voltage alarm is similar […]
Low Voltage Alarm Circuit
An alarm that gives indication of a low battery voltage, discharged at around 10.5 Volts in vehicles such as Boats and Cars can be made using a simple circuit. It […]
Vibration Activated Alarm Circuit
The noise or vibration activated alarm circuit displayed in this article makes use of its pre-installed loudspeaker like a microphone while it is within the sland- by-state. How the […]
Keypad Lock Circuit using a Single IC
The post explains a simple failproof digital keypad security lock circuit using a keypad module and a single CMOS IC . Introduction A decimal keyboard, a CMOS IC, about three […]
Anti-Theft Tracker Alarm Circuit for Protecting valuable
The anti-theft tracker alarm Circuit explained in this article can be used for protecting any preferred valuable item by attaching the receiver device with it while the transmitter is positioned […]
Capacitive Proximity Sensor Alarm Circuit
The discussed capacitive proximity sensor alarm circuit is composed of a transistor TR1 NPN BC107 (or similar) fitted in oscillator and operating a Darlington TR2 NPN BC517 accustomed to push […]