Multiple Choice
Identify the
choice that best completes the statement or answers the question.
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1.
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T7C01 What is the primary purpose of a dummy
load?
a. | To prevent transmitting signals over the air when making
tests | c. | To improve the efficiency of an
antenna | b. | To prevent over-modulation of a
transmitter | d. | To improve the signal-to-noise ratio of a
receiver |
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2.
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T7C02 Which of the following instruments can
be used to determine if an antenna is resonant at the desired operating frequency?
a. | A VTVM | c. | A Q
meter | b. | An antenna analy2er | d. | A frequency
counter |
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3.
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T7C03 What, in general terms, is standing
wave ratio (SWR)?
a. | A measure of how well a load is matched to a
transmission line | c. | The transmitter efficiency
ratio | b. | The ratio of high to low impedance in a feed
line | d. | An indication of the quality of your station's ground
connection |
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4.
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T7C04 What reading on an SWR meter indicates
a perfect impedance match between the antenna and the feed line?
a. | 2 to 1 | c. | 1 to
1 | b. | 1 to 3 | d. | 10 to
1 |
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5.
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T7C05 Why do most solid-state amateur radio
transmitters reduce output power as SWR increases?
a. | To protect the output amplifier
transistors | c. | Because power supplies cannot supply enough current at
high SWR | b. | To comply with FCC rules on spectral
purity | d. | To improve the impedance match to the feed
line |
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6.
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T7C06 What does an SWR reading of 4:1
indicate?
a. | LOSS Of -4 dB | c. | Gain
of +4 dB | b. | Good impedance match | d. | Impedance
mismatch |
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7.
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T7C07 What happens to power lost in a feed
line?
a. | It increases the SWR | c. | It is converted into heat | b. | It comes back into your transmitter and could cause
damage | d. | It can cause distortion of your signal |
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8.
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T7C08 What instrument other than an SWR meter
could you use to determine if a feed line and antenna are properly matched?
a. | Voltmeter | c. | Iambic
pentameter | b. | Ohmmeter | d. | Directional
wattmeter |
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9.
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T7C09 Which of the following is the most
common cause for failure of coaxial cables?
a. | Moisture contamination | c. | The velocity factor exceeds 1.0 | b. | Gamma rays | d. | Overloading |
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10.
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T7C10 Why should the outer jacket of coaxial
cable be resistant to ultraviolet light?
a. | Ultraviolet resistant Jackets prevent harmonic
radiation | c. | Ultraviolet and RF signals can mix, causing
interference | b. | Ultraviolet light
can increase losses in the cable's Jacket | d. | Ultraviolet light
can damage the Jacket and allow water to enter the cable |
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11.
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T7C11 What is a disadvantage of air core coaxial
cable when compared to foam or solid dielectric types?
a. | It has more loss per foot | c. | It requires special techniques to prevent water
absorption | b. | It cannot be used
for VMF or UHF antennas | d. | It cannot be used at below freezing
temperatures |
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12.
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T7C12 What does a dummy load consist
of?
a. | A high-gain amplifier and a TR
switch | c. | A low-voltage power supply and a DC
relay | b. | A non-inductive resistor and a heat
sink | d. | A 50 ohm reactance used to terminate a transmission
line |
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