3–62.
Internal arcing in a waveguide
is usually a symptom of which
of the following conditions?
1.
Change in mode
2.
Electrolysis at a joint
3.
Moisture in the waveguide
4.
Gradual change in frequency
3-63.
What is the primary purpose of
a directional coupler?
1.
To sample the energy in a
waveguide
2.
To change the phase of the
energy in the waveguide
3.
To change the direction of
energy travel in the
waveguide
4.
To allow energy in the
waveguide to travel in one
direction only
3-64.
What is the electrical distance
between the two holes in a
simple directional coupler?
1.
1/8 wavelength
2.
1/4 wavelength
3.
1/2 wavelength
4.
3/4 wavelength
3-65.
Of the following
characteristics, which is NOT
required for a device to be
considered a resonant cavity?
1.
Be enclosed by conducting
walls
2.
Possess resonant properties
3.
Contain oscillating
electromagnetic fields
4.
Be round or elliptical in
shape
3-66.
What property gives a resonant
cavity a narrow bandpass and
allows very accurate tuning?
1.
Low Q
2.
High Q
3.
Inductive reactance
4.
Capacitive reactance
3-67.
What factor(s) determine(s) the
primary frequency of a resonant
cavity?
3-68.
Tuning is the process of
changing what property of a
resonant cavity?
1.
The Q
2.
The power
3.
The cutoff frequency
4.
The resonant frequency
3-69.
What are the two basic types of
waveguide T junctions?
1.
H and T
2.
H and E
3.
Hybrid Ring and
magic T
4.
Q and
magic T
3-70.
A waveguide junction in which
the arm area extends from the
main waveguide in the same
direction as the electric field
is an example of what type
junction?
1.
E–type T
2.
H-type T
3.
H-type T junction
4.
H–type junction
3-71.
Low power handling capabilities
and internal power losses are
the primary disadvantages of
which of the following
junctions?
1.
Magic T
2.
Rat race
3.
Duplexer
4.
Hybrid ring
3-72.
The hybrid ring is usually used
as what type of device in radar
systems?
1.
Mixer
2.
Detector
3.
Duplexer
4.
Impedance matcher
1.
Size only
2.
Shape only
3.
Size and shape
4.
Q of the cavity
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