OPMWCS

The production of power at higher frequencies is much simpler than production of power at low frequencies.

• a) True

• b) False

Microwave tubes are power sources themselves at higher frequencies and can be used independently without any other devices.

• a) True

• b) False

Microwave tubes are grouped into two categories depending on the type of:

• a) Electron beam field interaction

• b) Amplification method

• c) Power gain achieved

• d) Construction methods

The klystron tube used in a klystron amplifier is a _________ type beam amplifier

• a) Linear beam

• b) Crossed field

• c) Parallel field

• d) None of the mentioned

________ is a single cavity klystron tube that operates as on oscillator by using a reflector electrode after the cavity.

• a) Backward wave oscillator

• b) Reflex klystron

• c) Travelling wave tube

• d) Magnetron

A major disadvantage of klystron amplifier is:

• a) Low power gain

• b) Low bandwidth

• c) High source power

• d) Design complexity

Klystron amplifiers have high noise output as compared to crossed field amplifiers.

• a) True 

• b) False

Magnetrons are microwave devices that offer very high efficiencies of about 80%.

• a) True

• b) False

Reflex Klystron is a

• a) Low Power Generator

• a) High Power Generator

• a) Low Gain Amplifier

• Not an Oscillator

The modes in a reflex klystron

• give the same frequency but different transit time

• result from excessive transit time across the resonator gap

• are caused by spurious frequency modulation

• all give much the same frequency but different times