1. A SIGNAL VOLTAGE TAKE OFF DEVICE COMPRISING A COAXIAL CABLE INCLUDING AN OUTER TUBULAR CONDUCTOR AND A CENTRAL CONDUCTOR, SAID OUTER CONDUCTOR HAVING AN ANNULAR GAP THEREIN PROVIDING AN IMPEDANCE ACROSS SAID GAP WHICH IS SMALL RELATIVE TO THE CHARACTERISTIC IMPEDANCE OF SAID CABLE, A PLURALITY OF CONNECTING COAXIAL CABLES CONNECTED IN PARALLEL ACROSS SAID GAP AT ONE OF THEIR ENDS, SAID CONNECTING CABLES HAVING CHARACTERISTIC IMPEDANCES PROVIDING A RESULTING PARALLEL CHARACTERISTIC IMPEDANCE ACROSS SAID GAP WHICH IS SMALL RELATIVE TO THE CHARACTERISTIC IMPEDANCE OF SAID FEED THROUGH CABLE, AN OUTPUT COAXIAL CABLE, THE OTHER ENDS OF SAID CONNECTING CABLES BEING CONNECTED AT LEAST PARTLY IN SERIES ACROSS ONE END OF SAID OUTPUT CABLE TO PROVIDE A RESULTANT CHARACTERISTIC IMPEDANCE APPROXIMATING THE CHARACTERISTIC IMPEDANCE OF SAID OUTPUT CABLE, AND MEANS FOR ELECTRICALLY ISOLATING THE OPPOSITE ENDS OF AT LEAST CERTAIN OF SAID CONNECTING CABLES TO PROVIDE FOR CONNECTING SAID ONE ENDS IN PARALLEL AND SAID OTHER ENDS AT LEAST PARTLY IN SERIES, SAID MEANS INCLUDING AN ANNULAR CORE OF MAGNETIC MATERIAL THROUGH WHICH SAID CERTAIN CONNECTING CABLES ARE PASSED, SAID CONNECTING CABLES ALL HAVING THE SAME EFFECTIVE LENGTH AND DIFFERENT ONES OF SAID CERTAIN CONNECTING CABLES BEING PASSED THROUGH SAID CORE A DIFFERENT NUMBER OF TIMES.