Project 1 - DTMF Decoder Project

• This project decodes touch-tones and allow you to control external devices.
  
• It will give 20 distinct outputs based on how the touch-tones are received.
• The upper bank of outputs is activated by using the '*' key and the lower bank is activated by using the '#' key.
• The '*' key might be considered as an ON.
• The '#' key might be considered on OFF.
• This would yield 10 pairs of commands or each output could be used independently to yield 20 outputs.
• Use SSI202 decoder chip as the dtmf detector and decoder.
• Use 74175 as latch to hold the selected number.
• Use 7485 as comparator.
• Good project for the learning of decoder concept and principal.

Further information go to the website DTMF Decoder