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HAM
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Readiness
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Checkpoint
Group T7C
11 questions from the official pool, drawn by ID — exact wording, never retyped.
T7C01
What is the primary purpose of a dummy load?
A
To prevent transmitting signals over the air when making tests
B
To prevent over-modulation of a transmitter
C
To improve the efficiency of an antenna
D
To improve the signal-to-noise ratio of a receiver
T7C02
Which of the following is used to determine if an antenna is resonant at the desired operating frequency?
A
A VTVM
B
An antenna analyzer
C
A Q meter
D
A frequency counter
T7C03
What does a typical RF dummy load consist of?
A
A low-voltage power supply and an AC relay
B
A 50-ohm non-inductive resistor mounted on a heat sink
C
A low-voltage power supply and a DC relay
D
A 50-ohm inductive reactance mounted in a shielded enclosure
T7C04
What reading on an SWR meter indicates a perfect impedance match between the antenna and the feed line?
A
50:50
B
Zero
C
1:1
D
Full Scale
T7C05
Why do most solid-state transmitters reduce output power as SWR increases beyond a certain level?
A
To protect the RF output amplifier transistors
B
To comply with FCC rules on spectral purity
C
Because power supplies cannot supply enough current at high SWR
D
To lower the SWR on the transmission line
T7C06
What does an SWR reading of 4:1 indicate?
A
Loss of -4 dB
B
Good impedance match
C
Gain of +4 dB
D
Impedance mismatch
T7C07
What happens to power lost in a feed line?
A
It increases the SWR
B
It is radiated as harmonics
C
It is converted into heat
D
It distorts the signal
T7C08
Which instrument can be used to determine SWR?
A
Voltmeter
B
Ohmmeter
C
Iambic pentameter
D
Directional wattmeter
T7C09
Which of the following causes failure of coaxial cables?
A
Moisture contamination
B
Solder flux contamination
C
Rapid fluctuation in transmitter output power
D
Operation at 100% duty cycle for an extended period
T7C10
Why should the outer jacket of coaxial cable be resistant to ultraviolet light?
A
Ultraviolet light can increase the resistance of the conductors
B
Ultraviolet light can increase losses in the cable's jacket
C
Ultraviolet and RF signals can mix, causing interference
D
Ultraviolet light can damage the jacket and allow water to enter the cable
T7C11
What is an advantage of foam-dielectric versus solid-dielectric coaxial cable?
A
It is more resistant to moisture contamination
B
It has higher voltage breakdown
C
It has less loss per foot
D
It has a better impedance match to 50 ohms
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