Klystrons, Traveling Wave Tubes, Magnetrons,
Crossed-Field Amplifiers, and Gyrotrons
RF Cafe Quiz #38

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RF Cafe Quiz - Klystrons, Traveling Wave Tubes, Magnetrons, Crossed-Field Amplifiers, and GyrotronsThis quiz is based on the information presented in Klystrons, Traveling Wave Tubes, Magnetrons, Crossed-Field Amplifiers, and Gyrotrons, by A.S. Gilmour, Jr., published by Artech House. Note: Some of these books are available as prizes in the monthly RF Cafe Giveaway.

1.  What is an important property of a metal to be useful as an electron emission
     source for tube cathodes?

a)  High atomic number
b)  Low atomic number
c)  High work function
d)  Low work function

2.  What is a primary obstacle that must be dealt with when designing a beam
      former for an electron gun?

a)  DoD security clearances
b)  Inter-electron repulsion forces
c)  Rare earth magnet scarcity
d)  Relativistic time dilation

3.  Which two forces must be exactly balanced in order to form an electron beam with uniform flux density?

a)  Space charge and centrifugal forces
b)  Gravity and centripetal forces
c)  Kinetic and potential energy forces
d)  Nuclear weak and nuclear strong forces

4.  Name the two major classes of linear-beam tubes.

a)  Cathode ray tube and anode ray tube
b)  Triode and pentode
c)  Laser and phaser
d)  Klystron and traveling wave tube

5.  In which ways can a conventional klystron be tuned?

a)  Synchronously tuned
b)  Efficiency tuned
c)  Broadband tuned
d)  All the above

6.  What are the two basic types of traveling wave tubes (TWTs)?

a)  Forward-bias and reverse-bias
b)  Narrowband and broadband
c)  Helix and coupled-cavity
d)  Glass tube and metal tube

7.  What are the two basic kinds of cross-field amplifiers (CFAs)?

a)  Cross beam and perpendicular beam
b)  Injected beam and distributed emission
c)  Reticulated beam and focused beam
d)  Mad beam and upset beam

8.  What is the primary difference between a gyrotron device and a linear-beam device?

a)  Electrons in a gyrotron rotate along path rather than just linear motion of a linear-beam
b)  A gyrotron uses a rotating motor whereas linear-beam does not
c)  Gyrotrons use a radioactive source of electrons rather than noble metals of al inear-beam
d)  There is no major difference

9.  What is one of the most common problems that plague microwave tubes?

a)  Radiation leakage
b)  Low efficiency
c)  Large physical size
d)  Electrical breakdown

10.  How is the transition between the vacuum of a tube cavity and the outside world accomplished?

a)  A waveguide or coaxial window.
b)  The entire transmission path is pressurized
c)  The entire transmission path is evacuated
d)  The entire transmission path is backfilled with dry nitrogen

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