drilled through the assembly without exposing wire 186 or hole 194 may be provided prior to the final de airing step single turn secondary 180 is inserted through hole 194 ends of secondary 180 are connected to the x ray tube filament as shown in fig1 ends of wire 186 of filament transformer 102 are connected to the power supply it is thus seen that there is provided a power supply with both voltage and current loops for very efficient regulation of the voltage delivered by the power supply to the x ray tube while the illustrated frequency of the control signals for switching the regulator switch 56 and for driving the converter 81 84 are illustrated as 40 khz and 20 khz the invention comprises utilizing control signals with high frequency rates preferably above 10 khz the high frequency as used in this invention provides efficient transformation at high voltage transformer 88 with relatively little voltage wave distortion through the transformer at the high frequency also the use of the high frequency control signal in the regulator circuit permits very fast response time thus contributing to the low ripple voltage which is obtained with the power supply of this invention by.