1. The problem statement, all variables and given/known data I want to design a circuit that is able to differentiate an sms signal and also a telephone signal. What I mean is the telephone signal is when someone calls you. Example , when someone sms you , your circuit will detect the sms signal and LED 1 will light up (use to indicate the signal) or when someone is calling you , your circuit will detect the telephone signal , LED 2 will light up 2. Relevant equations 3. The attempt at a solution Can anyone give me some hints on where I can go about?