It was a big experiment for testing this circuits, a very versatile remote control circuit which is consist of DTMF decoder IC 8870 & 4 bit BCD to decimal 4028 IC, Four
binary outputs are connected to the inputs of BCD to decimal 4028
IC .You
can control up to 9 appliances by this circuit, out puts will be in latched form.Mobile
phone can be easily used with circuits, all the keypad button 1 to 9 will be used.i used this circuit for Car GPS remote control ,actually the output from the 4028 will be a latched on state due to the IC 8870 , this IC have latched output .any pin will remain active untile other code were not given the decoder by the any source like mobile or any other source.
