Term
Which range of frequencies to Microwaves cover? |
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Definition
Microwaves cover 1 GHz to 300 GHz range of frequencies. |
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Term
What precautions must be observed when working with microwaves? Why? |
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Definition
Watch out for the heat, radiation, and high voltage when working with microwaves. One would want to be cautious because these things could result in death. |
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Term
State the primary mode of microwave propagation. |
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Definition
The primary mode of microwave propagation is line of sight. |
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Term
Define mircrowave repeater and explain its purpose and operation. |
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Definition
A microwave repeater receives a frequency, converts it to another frequency, amplifies that frequency, and retransmits that new frequency. Its purpose is it works like a satellite. |
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Term
What is a cavity resonator? |
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Definition
A cavity resonator is a precisely dimensioned enclosure that’s resonant to a specific frequency used to amplify and filter microwave energy. |
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Term
How does a cavity behave near resonance? |
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Definition
Near resonance, a cavity behaves like a tank circuit. |
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Term
Define waveguide and explain its structure. |
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Definition
A waveguide is precisely dimensioned hollow tubing used as a transmission line. |
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Term
What does LASER stand for? |
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Definition
LASER – Light amplification by stimulated emission of radiation |
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Term
What does MASER stand for? |
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Definition
MASER – Microwave amplification by stimulated emission of radiation |
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Term
List five examples of electron beam tubes. |
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Definition
Five examples of electron beam tubes: 1.CRT 2.Multi-cavity Klystron 3.Magnetron 4.Beam power tube (triodes and pentodes) 5.Photo-multiplier (light detector) |
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Term
Describe the klystron tube and list the most widely used types. |
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Definition
The klystron tube is a high energy device that RF is injected into. It increases the amount of energy. The most widely used types are multi-cavity klystron tubes and reflex klystron tubes. |
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Term
What is the function of the TWT magnetic field? |
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Definition
The function of the TWT magnetic field is that it forces the scattering of electrons which allows other electrons to be in phase with those fields. |
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Term
What is the function of the TWT electric field? |
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Definition
The function of the TWT electric field is used to focus and accelerate the electrons. |
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Term
What is the function of the TWT collector? |
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Definition
The function of the TWT collector is the high voltage potential terminal used to attract the electron energy. Also called the plate. |
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Term
State the function of the TWT grid. |
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Definition
The function of the TWT grid is that it turns the beam on and off. It controls the density of electrons. It also modulates the beam. |
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Term
How can the TWT be coupled to a waveguide? |
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Definition
The TWT can be coupled to a waveguide by coaxial cables at low frequencies, at high frequencies, it can be directly coupled to a waveguide. |
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Term
What precautions must be observed when handling a permanent magnet TWT? |
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Definition
When handling a permanent magnet TWT, the following precautions must be observed. Don’t drop it. Use non-magnetized tools. |
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