REMOTE CONTROL VIA PAGER

Introduction:

This is a very useful device. It allows you to remotely switch on/off one or two equipment connected to its 220V outputs. It can handle loads up to 15 amps in each output.

The circuit is based on an Atmel 89C2051, a nice microcontroller with 2k flash, UART, 128 bytes of RAM, 15 I/O lines and an analog comparator. By using this micro I have been able to design a very simple ONE chip circuit. The actual version has neither battery nor EEPROM which would allow it to remember the outputs states in case of mains failure, taking into account I have designed it to reset some paging transmitters that sometimes has the bad habit of hunging up. However, I am currently working on the circuit to include a serial EEPROM that will store some parameters like output status, device code and outputs and commands strings.

How it works?:

This device receives commands via Motorola Advisor pager. You simply have to send a message like this:

HOME LIGHTS ON

or

HOME HVAC OFF

the first message tells the pager to switch on your house lights, the second one switches off your home HVAC system. You are able to share only one pager number with different devices without disturbing one another, you just have to assign them diferent names (home, work, car, etc).