US Patent 7687936 Audio and video back-up power block

An uninterruptible power supply having an input connector for receiving AC power from a centralized source of electric power such as a power grid of an electric utility company, a first electric outlet, and a second electric outlet for delivering AC power, a first switch for selectively allowing AC power therethrough to the first outlet, a second switch for selectively allowing AC power therethrough to the second outlet: and a controller operable to control the second switch so that AC power is delivered to the second outlet a predetermined amount of time after AC power is delivered to the first outlet (i.e., after a time delay).