touchtone phone_number sound
str = '6142358970'; %% random phone number fs = 8000; % sample frequency tmax = 0.1; % tone duration t = linspace(0,tmax,tmax*fs+1); y = zeros(1,400); for k=1:length(str); y = [y DTMF_key(str(k),t) zeros(1,800)]; end sound(y,fs); wavwrite(y,fs,'random.wav');