Tag: DIY Homemade Door Alarm

Selective Door Chime Circuit Diagram

Selective Door Chime Circuit Diagram

The chime is for use in situations where there is bell or chime at the front door as well as at the back door. When loud bells or chimes are used, it may be difficult to determine which one is being rung. This Selective Door Chime Circuit will solve this problem which can produce two or three different sounds. When two of these circuits are built, the one at the front door is set to produce, say, two tones, and the one at the rear door, three tones.

PIR Controlled Shop Bell Circuit Diagram

PIR Controlled Shop Bell Circuit Diagram

The circuit is easy to build by anyone with basic electronics knowledge. Using 4013, CNY65, 4093 ICs, and BC517 transistor, the shop bell can be made and customized as per requirements. By using a PIR sensor, the bell will only ring when someone approaches the sensor, making it more efficient and suitable for the environment. It’s a cost-effective and straightforward solution that you can implement in your store today.

General Purpose Alarm Circuit Diagram

General Purpose Alarm Circuit Diagram

The general purpose alarm is a versatile circuit capable of generating an audible alarm. The astable multivibrator generates a square wave output, which is then amplified by the BC547 transistor, driving a speaker or buzzer. The circuit can be used in various applications, including door alarms, motion detection alarms, water level detection alarms, temperature alarms, fire alarms, and car alarms. The low-power consumption of the circuit makes it ideal for battery-operated applications.