Eng.SalahEddin

hello everybody.... i've been asked to get an electronic system that used often in T.V competitions.... In my university , me and group of my friends establishd "Cultural Club". and we are preparing for a competition between the faculties in our Uni.. What we need is that system which makes the competitors , two groups playing against each other , to press on button or something and the group who presses before the another one has the right to answer the question and a lamp illuminates refering to the fastest group...then it turns off when the question is answered... it's very important that the time of answering the question(pressing the buttons) between these two groups is very very small.... So is this circuit or system available in Markets...or i should design this system.... if i should Design it....plz.....Help me....what is the Idea of this Design??? I need it .... P.s i study Electronics and Communication Engineering..3rd year.... Thaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaanks

:-\ this is a system described by this 2nd order difference equation: y[n] + y[n-1] + 1/4 y[n-2] = x[n] jw find H( e ) ? find the expanded form using Partial Fraction Expansion? find the impulse response h[n]? find the step response S[n] using convolution? is this system oscillatory??? plzzz help me with this problem....