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Magnets of type MAEP30HSs
(produced according to the registered technical specifications
ТУ 1984-001-18785310-2003
of the Megapolis Technologies, Ltd.) are widely applied
for the focusing systems with regular and reversal magnetic fields
used in single- and multibeam klystrons.
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Photo: Magnetic focusing systems of klystrons
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| Outstanding hysteresis parameters of the Nd-Fe-B
magnets of type MAEP30HSs
play a key role in reducing the overall mass of the magnetic systems
in mobile devices. Moreover, the cost/performance considerations
become important in commercial production when the magnetic system
mass reaches tens of kilograms. |
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Figure 1. Design of a magnetic focusing
system for a floating-drift klystron
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Figure 3 shows the field pattern of a reversal magnetic
focusing system with two reversals of the field. The system called
"Tulip" is produced according to the technical specifications
МАЕР.684116.125 and applied in a multibeam (29 beams) pulsed amplifying
klystron with a screened cathode.
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Figure 2. Field
pattern, distribution of the longitudinal (BZ) and transversal
(Br) components of the magnetic field, and the pulsations of the
central and peripheral parts of the electron beam about the center
of one of the flight channels in an wide band amplifying klystron.
R0 is the flight channel radius.
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This systems features the following parameters: narrow field reversal
regions, homogeneity of the longitudinal field in regular regions
better than 4%, and transversal field component along the beam below
3 mTesla. This ensures a high current flow ratio in the device.
Up to date 18 magnetic focusing devices (with and without field
reversal) are produced commercially. Eight more devices are under
development. |
