Abstract: Redundant load sharing power supplies may use lower amperage pilot fuses to monitor the condition of higher amperage main line fuses carrying load current. An alarm monitoring circuit is activated when the pilot fuse has blown. The load sharing characteristics of these supplies may proportion current such that the pilot fuse may not be blown when the main line fuse is missing or blown. An embodiment of the present invention provides a system for ensuring activation of a power distribution alarm monitoring circuit in a load sharing power application using multiple loads to draw current from the power inputs. A control circuit enables current to flow in a controlled manner to blow the pilot fuse to ensure activation of a power distribution alarm monitoring circuit. Ensuring activation of the alarm monitoring circuit allows accurate identification of a faulty supply and satisfies a required operations condition of many telecommunications systems providers.

Abstract: Disclosed is a three-way call detection system that uses digital signal processing to identify a third party connection. The disclosed invention operates by establishing a baseline ambient, or background, noise level, and detecting when the signal noise level drops below the ambient noise level. When the current signal noise level drops below the ambient noise level, the system assumes that a three-way conference call has been attempted by the called party.