automatic billboard annoyance. please help!
i am doing this project that would change the face of a billboard four times automatically using time-delay and relays. how can this be achieved?

 

Please do not "hijack" another person's thread with off-topic question.

Is the billboard one of the new LED types, or one of the old "venetian blind" types? Will you be changing between four images? Or will you be changing between two images four times? Will there be only four changes, or will a sequence of four changes repeat?