Relay

Claim 1

A CONTROL DEVICE COMPRISING A GASEOUS ELECTRON TUBE HAVING AN ANODE, A CATHODE AND A CONTROL GRID AND OF THE TYPE ADAPTED TO BE FIRED UNDER CONDITIONS OF NEGATIVE POTENTIAL OF THE CONTROL GRID WITH RESPECT TO THE CATHODE, A TRANSFORMER HAVING ITS PRIMARY ARRANGED FOR CONNECTION TO AN ALTERNATING SUPPLY LINE WITH A GROUNDED SIDE, MEANS CONNECTING ONE END OF THE PRIMARY OF SAID TRANSFORMER TO THE ANODE OF THE ELECTRON TUBE, MEANS CONNECTING TOGETHER AND TO THE CATHODE OF THE ELECTRON TUBE THE OTHER END OF THE TRANSFORMER PRIMARY AND THAT END OF A SECONDARY THEREOF WHICH IS AT ANY INSTANT POLARIZED OPPOSITELY TO THE LAST MENTIONED END OF THE TRANSFORMER PRIMARY, MEANS CONNECTED TO SAID TRANSFORMER SECONDARY TO SUPPLY AN ALTERNATING CURRENT NON-FIRING BIAS POTENTIAL TO SAID CONTROL GRID WHEN THE ELECTRON TUBE ANODE IS POSITIVE WITH RESPECT TO ITS CATHODE, A CONTROL TERMINAL CONNECTED TO SAID CONTROL GRID, AND MEANS ACTUATED BY FIRING OF SAID ELECTRON TUBE, SAID DEVICE BEING SUCH THAT THE CAPACITY TO GROUND OF A PERSON CONTACTING SAID CONTROL TERMINAL WILL EFFECT FIRING OF THE ELECTRON TUBE WHEN THE GROUNDED END OF THE TRANSFORMER PRIMARY IS CONNECTED TO THE ELECTRON TUBE ANODE AND IS POSITIVE WITH RESPECT TO THE UNGROUNDED END OF THE TRANSFORMER PRIMARY.