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Hobby Circuits

Build Your Own Door Knob Touch Alarm Circuit

Last updated on 13 June 2026 by Admin-Lavi Leave a Comment

Todays time safety is very important, so this Build Your Own Door Knob Touch Alarm Circuit can help protect home and office. Also, this small project is Door Knob Touch Alarm using 555 IC, which can sense when someone touches the door knob. Furthermore, if someone touches then alarm makes loud sound and it scares […]

Filed Under: 555 Timer Projects, Alarm Circuits, Hobby Circuits, Security and Protection

Building a Smart Pet Feeder Circuit using Arduino

Last updated on 13 June 2026 by Admin-Lavi Leave a Comment

Feeding pets can be easy and on time using automatic system. This project for Building a Smart Pet Feeder Circuit using Arduino and other parts like IC 7809, SG90 servo motor and HC-SR04 sensor to make simple pet feeder. Feeder work with distance sensor to give food so pet can eat on time without people […]

Filed Under: Arduino Projects, Automation Circuits, Hobby Circuits, IoT projects, Sensors and Detectors

Reverse Car Parking Sensor Circuit using IC LM358

Last updated on 13 June 2026 by Admin-Lavi Leave a Comment

Modern cars must have reverse parking sensors, as these give sound and light signals to help driver avoid crash when going back. Sensors use infrared or ultrasonic to find objects behind car. Also, this article for Reverse Car Parking Sensor Circuit using IC LM358 op-amp is to make simple reverse parking sensor circuit. Here, the […]

Filed Under: Automobile Circuits, DIY Projects, Hobby Circuits, Sensors and Detectors

Digital Code Lock Circuit using Arduino

Last updated on 11 June 2026 by Admin-Lavi Leave a Comment

Nowadays, security is important everywhere in the world, and it becomes even more critical in sensitive or restricted areas. Therefore, this Digital Code Lock Circuit using Arduino helps improve security by providing controlled access. Also, it use Arduino, small computer to make simple lock and with Arduino UNO, keypad, buzzer, LCD (16×2), BC547 transistor and […]

Filed Under: Arduino Projects, Automation Circuits, Hobby Circuits, Security and Protection

Simple Heartbeat Monitor Circuit using Arduino

Last updated on 11 June 2026 by Admin-Lavi Leave a Comment

In this post we will show how to make Simple Heartbeat Monitor Circuit using Arduino. First, when we put finger on sensor it count heartbeats per minute and this is important because heartbeat tells doctor about our health. Here, we use Arduino UNO, LCD screen, two buttons, one resistor and heartbeat sensor to build it; […]

Filed Under: Arduino Projects, Hobby Circuits, Indicator Circuits

Simple Servo Motor Controller Circuit using Arduino

Last updated on 11 June 2026 by Admin-Lavi Leave a Comment

Servo motor is small machine part that can turn to exact position and also people use it in many things like robots, CNC machines and factory machines. Furthermore, this post for Simple Servo Motor Controller Circuit using Arduino show how to control servo motor using Arduino; it also use push buttons, capacitors, resistors and IC […]

Filed Under: Arduino Projects, Hobby Circuits, Motor Controllers

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