Capacity alarm system

Claim 1

A CAPACITANCE OPERATED INDICATING SYSTEM COMPRISING A SOURCE OF ALTERNATING CURRENT ELECTRCIAL ENERGY, ANTENNA MEANS ENERGIZED BY SAID SOURCE FOR PROVIDING A CAPACITANCE ACROSS AN AREA BE PROTECTED, CAPACITY MONITORING MEANS INCLUDING IMPEDANCE ELEMENTS CONNECTED TO SAID ANTENNA MEANS TO FORM A BRIDGE CIRCUIT THEREWITH, PHASE SENSITIVE DETECTOR MEANS HAVING AN INPUT CONNECTED TO SAID MONITORING MEANS AND HAVING AN OUTPUT FOR PRODUCING AT SAID OUTPUT A SIGNAL WHICH CHANGES IN VALUE WHEN SAID CAPACITANCE CHANGES IN VALUE, ELECTRICALLY OPERABLE MEANS, RATE SENSITIVE MEANS CONNECTED BETWEEN SAID DETECTOR MEANS OUTPUT AND SAID ELECTRICALLY OPERABLE MEANS FOR OPERATING SAID ELECTRICALLY OPERABLE MEANS WHEN THE OUTPUT OF SAID DETECTOR MEANS CHANGES AT GREATER THAN A PREDETERMINED RATE, AND VOLTAGE RESPONSIVE MEANS CONNECTED BETWEEN SAID DTECTOR MEANS OUTPOUT AND SAID ELECTRICALLY OPERABLE MEANS TO PROVIDE A CURRENT PATH BETWEEN SAID DETECTOR MEANS AND SAID ELECTRICALLY OPERABLE MEANS TO OPERATE SAID ELECTRICALLY OPERABLE MEANS INDEPENDENTLY OF SAID RATE SENSITIVE MEANS WHEN AN EXCESSIVE CHANGE IN THE OUTPUT SIGNAL OF SAID DETECTOR MEANS RESULTS FROM AN EXCESSIVE DEGREE OF UNBALANCE OF SAID BRIDGE.