RF Controlled Home Appliance Circuit

Circuit Description:

Transmitter

This circuit consists of Transmitter and Receiver section. The circuit can be used to control home appliances within a range of 30 meters. In open area, you can expect a range of 100 meters. The circuit comprises HT12 Encoder and Decode IC's. HT12 Encoder is used in the transmitter (remote) circuit where as HT12E is used in receiver circuit. The Encode IC encodes the 4 bits of data and transmit it serially to to RF Transmitter module. These 433Mhz transmitter and receiver modules operate using ASK Modulation.

Receiver:

For complete information regarding ASK Modulation, click here

The converse operation happens in the receiver section. The serial information is given to the decode section and the ICHT12D decodes the 4 bit data and gives across the data pins. The devices are then connected using the ULN2003 high voltage high current buffer.

These are some of the images of my own remote. You can design something like this. I had modified it and soldered with in the size of 9V battery. I will post that photos also very soon.

For entire range of photos of this project, click here ( you should be an orkut user to access them)

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