with one or more immovable internal control electrodes, e.g. triode, pentode, octode
21
/
12
•
•
•
•
Tubes with variable amplification factor
21
/
14
•
•
•
•
Tubes with means for concentrating the electron stream, e.g. beam tetrode
21
/
16
•
•
•
with external electrostatic control means and with or without internal control electrodes
21
/
18
•
•
having magnetic control means; having both magnetic and electrostatic control means
21
/
20
•
Tubes with more than one discharge path; Multiple tubes, e.g. double diode, triode-hexode (secondary-emission tubes, electron-multiplier tubes H 01 J 43/00)
21
/
22
•
•
with movable electrode or electrodes
21
/
24
•
•
with variable amplification factor
21
/
26
•
•
with means for concentrating the electron stream
21
/
34
•
Tubes with electrode system arranged or dimensioned so as to eliminate transit-time effect (with flat electrodes H 01 J 21/36)
21
/
36
•
Tubes with flat electrodes, e.g. disc electrode
23
/
00
Details of transit-time tubes of the types covered by group H 01 J 25/00
23
/
02
•
Electrodes; Magnetic control means; Screens (associated with resonator or delay system H 01 J 23/16)
23
/
027
•
•
Collectors [2]
23
/
033
•
•
•
Collector cooling devices [2]
23
/
04
•
•
Cathodes
23
/
05
•
•
•
having a cylindrical emissive surface, e.g. cathodes for magnetrons [3]
Focusing arrangements, e.g. for concentrating stream of electrons, for preventing spreading of stream
23
/
083
•
•
•
Electrostatic focusing arrangements [3]
23
/
087
•
•
•
Magnetic focusing arrangements [3]
23
/
09
•
•
Electric systems for directing or deflecting the discharge along a desired path, e.g. E-type (focusing arrangements H 01 J 23/08)
23
/
10
•
•
Magnet systems for directing or deflecting the discharge along a desired path, e.g. a spiral path (magnetic focusing arrangements H 01 J 23/08)
23
/
11
•
•
Means for reducing noise (in electron or ion gun H 01 J 23/06)
23
/
12
•
Vessels; Containers
23
/
14
•
Leading-in arrangements; Seals therefor
23
/
15
•
•
Means for preventing wave energy leakage structurally associated with tube leading-in arrangements, e.g. filters, chokes, attenuating devices [4]
23
/
16
•
Circuit elements, having distributed capacitance and inductance, structurally associated with the tube and interacting with the discharge (circuit elements, having distributed capacitance and inductance, in general
H 01 P)
23
/
18
•
•
Resonators
23
/
20
•
•
•
Cavity resonators; Adjustment or tuning thereof
23
/
207
•
•
•
•
Tuning of single resonator [2]
23
/
213
•
•
•
•
Simultaneous tuning of more than one resonator, e.g. resonant cavities of a magnetron [2]
23
/
22
•
•
•
Connections between resonators, e.g. strapping for connecting resonators of a magnetron
for linking interaction circuit with coaxial lines; Devices of the coupled helices type (H 01 J 23/46 takes precedence) [4]
23
/
50
•
•
•
•
the interaction circuit being a helix or derived from a helix (H 01 J 23/52 takes precedence) [4]
23
/
52
•
•
•
•
the coupled helices being disposed coaxially around one another [4]
23
/
54
•
•
Filtering devices preventing unwanted frequencies or modes to be coupled to, or out of, the interaction circuit; Prevention of high frequency leakage in the environment [4]
