Automatic security communications system

Claim 1

An automatic communications system adapted to provide security communications within an apartment building comprising, a central call station including a multiple action selector positioned in an entrance area and a plurality of telephone receivers positioned in the different apartments of said building, a main switch for shifting the communications system from its normal standby status to a service status, a first time delay circuit operative upon use of said multiple action selector to provide time for completing the desired selection before said main switch shifts back to standby status, a second time delay circuit operative upon completion of the desired selection to provide time for the selected receiver to be answered before said main switch shifts back to standby status, said second circuit including an alarm for the selected receiver, and a third time delay circuit operative upon the selected receiver being answered to discontinue the alarm and establish communication with said central call station for a time sufficient to conclude a brief conversation before said main switch shifts back to standby service permitting the central call station to be used for other calls even though the selected receiver is not hung up.