Uploaded January 2023 | Updated September 2026, 3 weeks ago
Revisiting an old experiment here, pulsing an oven magnetron, but with a different method to control the pulse width. The best solution appears to be in the form of a solid-state switch using Sic MOSFETs. These can be connected in series and switched together. In theory this means the switch breakdown voltage is the sum of the individual MOSFET breakdown voltages. With this arrangement it should be possible to construct a fast switch capable for tens of kV. The video looks at the design issues for switching magnetrons having grounded anodes, casings and waveguides. Unfortunately, the prototype switch fails during initial high voltage testing. One possible cause could have been adjusting the heater voltage as this also adjusts the gate voltage and may have under switched the MOSFETs while exposed to 4.5kV, causing a voltage imbalance on the chain.
Revisiting an old experiment here, pulsing an oven magnetron, but with a different method to control the pulse width. The best solution appears to be in the form of a solid-state switch using Sic MOSFETs. These can be connected in series and switched together. In theory this means the switch breakdown voltage is the sum of the individual MOSFET breakdown voltages. With this arrangement it should be possible to construct a fast switch capable for tens of kV. The video looks at the design issues for switching magnetrons having grounded anodes, casings and waveguides. Unfortunately, the prototype switch fails during initial high voltage testing. One possible cause could have been adjusting the heater voltage as this also adjusts the gate voltage and may have under switched the MOSFETs while exposed to 4.5kV, causing a voltage imbalance on the chain.
