Minimum Breakdown Level Limitations of voltage amplitude for inhibiting electron leakage Order Positive Voltage 1 Constant DC Voltage 2.5 VDC 2 Biased Unipolar Pulse 3 Gated Unipolar Pulse 4 Isolated VIC  Negative Voltage 5 Cathode Inline Resistor 8.5 VDC 6 SS Sandwich Material Infinity! 7 Resonant Cavity