preferably a switching device that can shut off or be shut off for example the switches may be solid state switches such as silicon controlled rectifiers scr gate turn off switches gto bipolar junction transistors bjt field effect transistors fet insulated gated bipolar transistors igbt or other transistor for example in one embodiment each switch comprises a transistor and a diode in series such that it behaves as an scr the switches may also be electromechanical switches such as a spark gap if the pulsing frequency is sufficient to allow the switch to turn off between pulses of the same inductor of the same module even if the switch has not turned off yet the closing of the next switch in the same module will act to shut off the previous switch in comparison to traditional pulse forming networks in many embodiments the number of switches increases however the total energy switched will remain the same and the size and mass of the switches is normally significantly less that the size and mass of the inductors thus even though there may be more switches present the overall mass and size of the pulse forming network is reduced due to the reduction in the number and size of inductors and a reduction in the number of anti reversing diodes it is also noted that compared to known pulse forming networks the switches are grouped together for example in fig1 each illustrated switch is a grouping of switches.