Cable testing system having stressing means for detecting open and short circuits

Claim 1

MEANS FOR TESTING A CABLE COMPRISING A PLURALITY OF CONDUCTORS, COMPRISING MEANS FOR CONNECTING SAID CONDUCTORS IN SERIES IN A BRIDGE CIRCUIT, WHEREBY SAID BRIDGE CIRCUIT IS BALANCED WHEN THERE IS NO DEFECT IN SAID CONDUCTORS, MEANS FOR APPLYING A FIRST ALTERNATING CURRENT POTENTIAL TO SAID BRIDGE CIRCUIT, AN AMPLIFIER FOR THE OUTPUT OF SAID BRIDGE CIRCUIT, THE OUTPUT OF SAID AMPLIFIER BEING CONNECTED TO THE CONTROL GRIDS OF A PAIR OF THYRATRON TUBES, MEANS FOR APPLYING A SECOND ALTERNATING CURRENT POTENTIAL SUBSTANTIALLY IN PHASE WITH SAID FIRST ALTERNATING POTENTIAL THROUGH THE COIL OF A FIRST RELAY TO THE ANODE OF ONE OF SAID TUBES, MEANS FOR APPLYING A THIRD ALTERNATING CURRENT POTENTIAL SUBSTANTIALLY 180* OUT OF PHASE WITH SAID FIRST ALTERNATING CURRENT POTENTIAL THROUGH THE COIL OF A SECOND RELAY TO THE ANODE OF THE OTHER OF THE SAID TUBES, DRIVING MEANS FOR PASSING SAID CABLE THROUGH A TESTING ZONE AND MEANS FOR CONCURRENTLY STRESSING AND BENDING SAID CABLE, MEANS ACTUATED AUTOMATICALLY UPON THE OCCURRENCE OF A SHORT CIRCUIT IN SAID CABLE TO STOP SAID DRIVING MEANS AND ACTUATE A FIRST INDICATOR AND MEANS ACTUATED AUTOMATICALLY UPON THE OCCURRENCE OF AN OPEN CIRCUIT IN SAID CABLE TO STOP SAID DRIVING MEANS AND ACTUATE A SECOND INDICATOR.