what happens when we press a button on telephone number pad. i know that it generates 2 frequencies . Why 2 frequency are needed to be generated. Why the tone should have low and high frequency component? How the tone is detected. my question is how can you detect frequency of signal by using Band pass or any kind of filter. If this is possible to detect frequencies by filters then what should be the input voltage of that filter. Does sinusoidal of square wave rally matter?
I have uploaded project
I have uploaded project
Last edited: