Microwave power control apparatus for linear accelerator using hybrid junctions

Control apparatus for a linear accelerator comprising a charged particle source for generating charged particles, and first and second accelerator guide sections operatively connected in series for accelerating said charged particles therethrough, said control apparatus comprising:

• a first hybrid junction having a first port for receiving input RF power, a second port coupled to said first accelerator guide section, a third port coupled to a dummy load, and a fourth port;
• a second symmetric hybrid junction having a first port coupled to the fourth port of said first hybrid junction, a third port coupled, in parallel, to the connection of the first hybrid junction to the first accelerator guide section by being connected to said second accelerator guide section, and second and fourth ports;
• a first variable short circuit element coupled to the second port of said second symmetric hybrid junction;
• a second variable short circuit element coupled to the fourth port of said second symmetric hybrid junction, wherein the input RF power reflected by said first and second variable short circuit elements is controllably directed through the third port of said second symmetric hybrid junction to said second accelerator guide section in parallel with the input RF power fed to said first accelerator;
• and
• control means, operatively connected to said first and second short circuit elements, for adjusting, said first and second variable short circuit elements so as to control said input RF power supplied to said accelerator guide sections to output an adjustable electron beam from said accelerator.

Control apparatus for controlling input RF power supplied to a first load and to a second load, said apparatus comprising:

• a first hybrid junction having a first port for receiving said input RF power, a second port coupled to said first load, a third port coupled to a dummy load, and a fourth port;
• a second hybrid junction having a first port coupled to the fourth port of said first hybrid junction, a third port coupled to said second load, and second and fourth ports;
• a first variable short circuit element coupled to the second port of said second hybrid junction;
• a second variable short circuit element coupled to the fourth port of said second hybrid junction, wherein said input RF power fed to and reflected by said first and second variable short circuit elements is controllably directed through the third port of said second hybrid junction to said second load;
• and control means, operatively connected to said first and second short circuit elements, for adjusting said first and second variable short circuit elements so as to control the input RF power supplied to said second load.