This project is used as an electronic private exchange. It has two telephones, which have the intercom facility, and they can be connected to the telephone line. All the functions are controlled by the 8-bit microcontroller AT89C2051 which has an Pro

A simple PID fan controller with nice LCD display: It uses the input two precise DHT22 based temperature sensors. The MCU is an Arduino Uno, which is powered using a 12V power source.-A simple PID fan controller with nice LCD display: It uses the in