DTMF CONTROLLER
Control your electronic device using your cell phone, telephone or coin phone any where in the world
By studying this data sheet in the link bellow, we can easily understand how to construct a device that handles the signals from any cell phone or telephone sound out put device like headset speakers etc.
This link contains the data sheet of CM8870 which is DTMF to binary decoder
Availability: This IC CM8870 is available in many electronic shops.
Cost: the cost of this IC is approximately Rs45/-
It receives the DTMF signals from the sound out put port at such as cell phone headset speaker, and decodes it to the corresponding binary number. Hence we can directly use the out put logic or can decode it to any other formats like decimal, 7 segment etc.
CIRCUIT FOR CONTROLLING ONE DIVICE
it can be extended up to 4 with out any complicated sequential logic circuits or microcomputers.
This circuit can be used to control four devices
what is the use
ReplyDelete