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Magnets of type MAEP30HSs
(produced according to the registered technical specifications
ÒÓ 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 ÌÀÅÐ.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. |
