242 Remote-Control Household Devices Using Telephone Network

The paper introduces an intelligent remote control system based on a PSTN (public telephone network), the project mainly based on MT8870 DTMF decoder and Atmel 89S52 MCU. When this system connects to the phone line it monitor the status of the phone line and take the control of phone line when it detects the ringer, after that user may be able to control multiple household electric appliances by DTMF. The system hardware and software are designed based on the telephone standards.