An All Solid-State Line-Type Modulator for 10% Duty Factor

IKO has recently obtained approval of its proposal to build a high duty factor linear accelerator. Main characteristics of this machine: 500 MeV at 2¿% and 250 MeV at 10% d.f. R.F. power is to be obtained from 12 klystrons (100 kW av., 1-6 MW peak). A prototype modulator has been constructed. It consists of 48 modules, each of which is a printed circuit 2 kV line-type (50 ¿s) modulator. Each module feeds a primary winding of a special pulse transformer, in order to supply the 160 kV max. video pulses for the main klystron. The modulator lay-out allows the provision of video pulses, the amplitude of which can be regulated on a pulse to pulse basis with a special purpose processor. Cooling is achieved through the liquid vapor phase change of freon. Details of the system will be given together with first test results.