Which of the following is an important safety precaution to observe when putting up an antenna tower?

Look for and stay clear of any overhead electrical wires

What causes spin fading of satellite signals?

Rotation of the satellite and its antennas

What telemetry information is typically transmitted by satellite beacons?

Health and status of the satellite

What would cause a broadcast AM or FM radio to receive an amateur radio transmission unintentionally?

The receiver is unable to reject strong signals outside the AM or FM band

What is required before using the EchoLink system?

Register your call sign and provide proof of license

What is a characteristic of single sideband (SSB) compared to FM?

SSB signals have narrower bandwidth

What is the purpose of a safety wire through a turnbuckle used to tension guy lines?

Prevent loosening of the turnbuckle from vibration

Why should the outer jacket of coaxial cable be resistant to ultraviolet light?

Ultraviolet light can damage the jacket and allow water to enter the cable

Why is duty cycle one of the factors used to determine safe RF radiation exposure levels?

It affects the average exposure to radiation

What does a dummy load consist of?

A non-inductive resistor mounted on a heat sink

What hazard exists in a power supply immediately after turning it off?

Charge stored in filter capacitors

Which of the following is a disadvantage of FM compared with single sideband?

Only one signal can be received at a time

Why do exposure limits vary with frequency?

The human body absorbs more RF energy at some frequencies than at others

What is a grid locator?

A letter-number designator assigned to a geographic location

Where should a lightning arrester be installed in a coaxial feed line?

On a grounded panel near where feed lines enter the building

Why do most solid-state transmitters reduce output power as SWR increases beyond a certain level?

To protect the output amplifier transistors

What is a disadvantage of using a handheld VHF transceiver with a flexible antenna inside a vehicle?

Signal strength is reduced due to the shielding effect of the vehicle

What can cause erratic changes in SWR?

Loose connection in the antenna or feed line

Which of the following precautions should be taken when measuring in-circuit resistance with an ohmmeter?

Ensure that the circuit is not powered

Which of the following is true of PL-259 type coax connectors?

They are commonly used at HF and VHF frequencies

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Test test part 2

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Questions 119

Answers

1
Which of the following types of solder should not be used for radio and electronic applications?
Acid-core solder
Tin-copper solder
Rosin-core solder
Lead-tin solder
2
Which of the following could you use to cure distorted audio caused by RF current on the shield of a microphone cable?
Low-pass filter
Ferrite choke
Band-pass filter
Preamplifier
3
Which of the following is an important safety precaution to observe when putting up an antenna tower?
Look for and stay clear of any overhead electrical wires
Insulate the base of the tower to avoid lightning strikes
All these choices are correct
Wear a ground strap connected to your wrist at all times
4
What causes spin fading of satellite signals?
Rotation of the satellite and its antennas
Doppler shift of the received signal
Interfering signals within the satellite uplink band
Circular polarized noise interference radiated from the sun
5
What telemetry information is typically transmitted by satellite beacons?
Health and status of the satellite
Time of day accurate to plus or minus 1/10 second
All these choices are correct
The signal strength of received signals
6
What is a good way to guard against electrical shock at your station?
Connect all AC powered station equipment to a common safety ground
Install mechanical interlocks in high-voltage circuits
Use three-wire cords and plugs for all AC powered equipment
All these choices are correct
7
Which of the following actions can reduce exposure to RF radiation?
Increase the duty cycle
All these choices are correct
Relocate the transmitter
Relocate antennas
8
Which of these items would be useful for a hidden transmitter hunt?
All these choices are correct
Calibrated SWR meter
A directional antenna
A calibrated noise bridge
9
What would cause a broadcast AM or FM radio to receive an amateur radio transmission unintentionally?
The deviation of an FM transmitter is set too low
The microphone gain of the transmitter is turned up too high
The audio amplifier of the transmitter is overloaded
The receiver is unable to reject strong signals outside the AM or FM band
10
What is required before using the EchoLink system?
Purchase a license to use the EchoLink software
Complete the required EchoLink training
All these choices are correct
Register your call sign and provide proof of license
11
Which of the following is a source of loss in coaxial feed line?
High SWR
All these choices are correct
Multiple connectors in the line
Water intrusion into coaxial connectors
12
What is a characteristic of single sideband (SSB) compared to FM?
SSB signals are easier to tune in correctly
SSB signals are less susceptible to interference
All these choices are correct
SSB signals have narrower bandwidth
13
What is the approximate length; in inches; of a half-wavelength 6 meter dipole antenna?
236
50
112
6
14
Which of the following causes failure of coaxial cables?
Moisture contamination
Operation at 100% duty cycle for an extended period
Solder flux contamination
Rapid fluctuation in transmitter output power
15
Which instrument would you use to measure electric potential?
A wavemeter
An ohmmeter
An ammeter
A voltmeter
16
What is the purpose of a safety wire through a turnbuckle used to tension guy lines?
Secure the guy line if the turnbuckle breaks
Provide an ability to measure for proper tensioning
Prevent loosening of the turnbuckle from vibration
Provide a ground path for lightning strikes
17
Which of the following operating activities is supported by digital mode software in the WSJT-X software suite?
Earth-Moon-Earth
Meteor scatter
All these choices are correct
Weak signal propagation beacons
18
What is the most common impedance of coaxial cables used in amateur radio?
50 ohms
600 ohms
12 ohms
8 ohms
19
At which of the following frequencies does maximum permissible exposure have the lowest value?
50 MHz
1296 MHz
440 MHz
3.5 MHz
20
What is required when climbing an antenna tower?
Have sufficient training on safe tower climbing techniques
All these choices are correct
Always wear an approved climbing harness
Use appropriate tie-off to the tower at all times
21
Why should the outer jacket of coaxial cable be resistant to ultraviolet light?
Ultraviolet and RF signals can mix; causing interference
Ultraviolet light can damage the jacket and allow water to enter the cable
Ultraviolet light can increase losses in the cable’s jacket
Ultraviolet resistant jackets prevent harmonic radiation
22
Which of the following describes combining speech with an RF carrier signal?
Low-pass filtering
Impedance matching
Oscillation
Modulation
23
Why is duty cycle one of the factors used to determine safe RF radiation exposure levels?
It affects the average exposure to radiation
It takes into account the thermal effects of the final amplifier
It takes into account the antenna feed line loss
It affects the peak exposure to radiation
24
What mode of transmission is commonly used by amateur radio satellites?
All these choices are correct
SSB
FM
CW/data
25
What does a dummy load consist of?
A non-inductive resistor mounted on a heat sink
A 50-ohm reactance used to terminate a transmission line
A low-voltage power supply and a DC relay
A high-gain amplifier and a TR switch
26
What hazard exists in a power supply immediately after turning it off?
Voltage transients from kickback diodes
Circulating currents in the dc filter
Leakage flux in the power transformer
Charge stored in filter capacitors
27
How is a voltmeter connected to a component to measure applied voltage?
In quadrature
In parallel
In phase
In series
28
Which of the following is a disadvantage of FM compared with single sideband?
Only one signal can be received at a time
Voice quality is poorer
FM signals are harder to tune
All these choices are correct
29
Under what circumstances is it safe to climb a tower without a helper or observer?
When no electrical work is being performed
Never
When the work being done is not more than 20 feet above the ground
When no mechanical work is being performed
30
What happens as the frequency of a signal in coaxial cable is increased?
The characteristic impedance increases
The loss decreases
The loss increases
The characteristic impedance decreases
31
What kind of data can be transmitted by APRS?
GPS position data
Text messages
Weather data
All these choices are correct
32
How is over the air access to IRLP nodes accomplished?
By entering the proper internet password
By using DTMF signals
By obtaining a password that is sent via voice to the node
By using CTCSS tone codes
33
Why do exposure limits vary with frequency?
Lower frequency RF fields do not penetrate the human body
Higher frequency RF fields are transient in nature
Lower frequency RF fields have more energy than higher frequency fields
The human body absorbs more RF energy at some frequencies than at others
34
Which of the following increases the resonant frequency of a dipole antenna?
Lengthening it
Adding capacitive loading to the ends of the radiating wires
Inserting coils in series with radiating wires
Shortening it
35
What device converts the RF input and output of a transceiver to another band?
Phase converter
High-pass filter
Low-pass filter
Transverter
36
What is a grid locator?
A letter-number designator assigned to an azimuth and elevation
An instrument for neutralizing a final amplifier
A letter-number designator assigned to a geographic location
An instrument for radio direction finding
37
What happens to power lost in a feed line?
It increases the SWR
It is converted into heat
It distorts the signal
It is radiated as harmonics
38
Where should a lightning arrester be installed in a coaxial feed line?
At the antenna feed point
On a grounded panel near where feed lines enter the building
At the output connector of a transceiver
At the ac power service panel
39
Why do most solid-state transmitters reduce output power as SWR increases beyond a certain level?
To comply with FCC rules on spectral purity
Because power supplies cannot supply enough current at high SWR
To lower the SWR on the transmission line
To protect the output amplifier transistors
40
What is the function of component 2 in figure T-1?
Convert electrical energy into radio waves
Give off light when current flows through it
Control the flow of current
Supply electrical energy
41
What is a disadvantage of using a handheld VHF transceiver with a flexible antenna inside a vehicle?
The SWR might decrease; decreasing the signal strength
All these choices are correct
Signal strength is reduced due to the shielding effect of the vehicle
The bandwidth of the antenna will decrease; increasing SWR
42
Which of the following RF connector types is most suitable for frequencies above 400 MHz?
DB-25
RS-213
Type N
UHF (PL-259/SO-239)
43
Which of the following can cause radio frequency interference?
Fundamental overload
Spurious emissions
All these choices are correct
Harmonics
44
Which instrument can be used to determine SWR?
Directional wattmeter
Voltmeter
Iambic pentameter
Ohmmeter
45
What hazard is created by touching an antenna during a transmission?
Electrocution
RF burn to skin
All these choices are correct
Radiation poisoning
46
What can cause erratic changes in SWR?
Local thunderstorm
Loose connection in the antenna or feed line
Over-modulation
Overload from a strong local station
47
Which of the following precautions should be taken when measuring in-circuit resistance with an ohmmeter?
Ensure that the circuit is not powered
Ensure that the circuit is operating at the correct frequency
Ensure that the circuit is grounded
Ensure that the applied voltages are correct
48
What is a LEO satellite?
A satellite in low energy operation mode
A sun synchronous satellite
A highly elliptical orbit satellite
A satellite in low earth orbit
49
Which of the following is true of PL-259 type coax connectors?
They are commonly used at HF and VHF frequencies
They are watertight
They are a bayonet-type connector
They are preferred for microwave operation
50
What type of radiation are radio signals?
Ionizing radiation
Non-ionizing radiation
Alpha radiation
Gamma radiation
51
What is an amateur radio station that connects other amateur stations to the internet?
A gateway
A repeater
A beacon
A digipeater
52
What health hazard is presented by electrical current flowing through the body?
All these choices are correct
It may disrupt the electrical functions of cells
It may cause involuntary muscle contractions
It may cause injury by heating tissue
53
What factors affect the RF exposure of people near an amateur station antenna?
Distance from the antenna to a person
Frequency and power level of the RF field
Radiation pattern of the antenna
All these choices are correct
54
Which of the following establishes grounding requirements for an amateur radio tower or antenna?
FAA tower lighting regulations
FCC Part 97 rules
UL recommended practices
Local electrical codes
55
What is a benefit of low SWR?
All these choices are correct
Reduced television interference
Reduced signal loss
Less antenna wear
56
What is the approximate bandwidth of a VHF repeater FM voice signal?
Between 50 and 125 kHz
Between 10 and 15 kHz
Less than 500 Hz
About 150 kHz
57
Where should a fuse or circuit breaker be installed in a 120V AC power circuit?
In series with the hot and neutral conductors
In parallel with the hot conductor only
In parallel with the hot and neutral conductors
In series with the hot conductor only
58
What is the primary purpose of a dummy load?
To improve the efficiency of an antenna
To improve the signal-to-noise ratio of a receiver
To prevent over-modulation of a transmitter
To prevent transmitting signals over the air when making tests
59
What type of modulation is commonly used for VHF packet radio transmissions?
SSB
AM
FM or PM
PSK
60
How does the allowable power density for RF safety change if duty cycle changes from 100 percent to 50 percent?
It decreases by 50 percent
It increases by a factor of 3
There is no adjustment allowed for lower duty cycle
It increases by a factor of 2
61
In which direction does a half-wave dipole antenna radiate the strongest signal?
Broadside to the antenna
Off the ends of the antenna
In the direction of the feed line
Equally in all directions
62
Which of the following describes a simple dipole oriented parallel to Earth's surface?
A horizontally polarized antenna
A travelling-wave antenna
A ground-wave antenna
A vertically polarized antenna
63
What is the approximate bandwidth of AM fast-scan TV transmissions?
About 6 MHz
About 3 MHz
More than 10 MHz
About 1 MHz
64
What is the characteristic appearance of a cold tin-lead solder joint?
Dark black spots
A bright or shiny surface
Excessive solder
A rough or lumpy surface
65
Which of the following is true when installing grounding conductors used for lightning protection?
Common grounds must be avoided
Use only non-insulated wire
Sharp bends must be avoided
Wires must be carefully routed with precise right-angle bends
66
What is standing wave ratio (SWR)?
An indication of the quality of your station’s ground connection
The transmitter efficiency ratio
A measure of how well a load is matched to a transmission line
The ratio of amplifier power output to input
67
What device increases the transmitted output power from a transceiver?
An impedance network
A voltage divider
All these choices are correct
An RF power amplifier
68
What is the function of a transceiver’s PTT input?
Provides a transmit tuning tone when grounded
Input for a key used to send CW
Switches transceiver from receive to transmit when grounded
Input for a preamplifier tuning tone
69
Which term describes the ability of a receiver to detect the presence of a signal?
Selectivity
Sensitivity
Total Harmonic Distortion
Linearity
70
Which of the following types of feed line has the lowest loss at VHF and UHF?
Multi-conductor unbalanced cable
50-ohm flexible coax
75-ohm flexible coax
Air-insulated hardline
71
Which type of modulation is commonly used for VHF and UHF voice repeaters?
SSB
FM or PM
PSK
AM
72
Which of the following measurements are made using a multimeter?
Voltage and resistance
Impedance and reactance
Signal strength and noise
All these choices are correct
73
What is the name of a device that combines several semiconductors and other components into one package?
Transformer
Integrated circuit
Multi-pole relay
Transducer
74
Which sideband is normally used for 10 meter HF; VHF; and UHF single-sideband communications?
Upper sideband
Inverted sideband
Suppressed sideband
Lower sideband
75
Which of the following can damage a multimeter?
Not allowing it to warm up properly
Attempting to measure voltage when using the resistance setting
Attempting to measure resistance using the voltage setting
Failing to connect one of the probes to ground
76
Which of the following is combined with an inductor to make a resonant circuit?
Potentiometer
Capacitor
Resistor
Zener diode
77
Which of the following is a form of amplitude modulation?
Packet radio
Single sideband
Spread spectrum
Phase shift keying (PSK)
78
Who is responsible for ensuring that no person is exposed to RF energy above the FCC exposure limits?
The station licensee
The local zoning board
Anyone who is near an antenna
The FCC
79
What reading on an SWR meter indicates a perfect impedance match between the antenna and the feed line?
Zero
Full Scale
50:50
1:1
80
What is the approximate bandwidth required to transmit a CW signal?
15 kHz
1000 Hz
150 Hz
2.4 kHz
81
What does the abbreviation "PSK" mean?
Phase Shift Keying
Packet Short Keying
Phased Slide Keying
Pulse Shift Keying
82
Which of the following is commonly used as a visual indicator?
LED
FET
Zener diode
Bipolar transistor
83
What is CW?
A technique for coil winding
A digital mode used primarily on 2 meter FM
A type of electromagnetic propagation
Another name for a Morse code transmission
84
What is a symptom of RF feedback in a transmitter or transceiver?
Excessive SWR at the antenna connection
The transmitter will not stay on the desired frequency
Frequent blowing of power supply fuses
Reports of garbled; distorted; or unintelligible voice transmissions
85
What is the approximate bandwidth of a typical single sideband (SSB) voice signal?
15 kHz
3 kHz
1 kHz
6 kHz
86
Which instrument is used to measure electric current?
An ammeter
An ohmmeter
A voltmeter
An electrometer
87
Which of the following is a way to determine whether your satellite uplink power is neither too low nor too high?
Listen for distortion on your downlink signal
Check your signal strength report in the telemetry data
Your signal strength on the downlink should be about the same as the beacon
All these choices are correct
88
What can you do if you are told your FM handheld or mobile transceiver is over-deviating?
Talk louder into the microphone
Change to a higher power level
Let the transceiver cool off
Talk farther away from the microphone
89
Why should you avoid attaching an antenna to a utility pole?
The antenna could contact high-voltage power lines
The antenna will not work properly because of induced voltages
All these choices are correct
The 60 Hz radiations from the feed line may increase the SWR
90
Which of the following types of antenna offers the greatest gain?
Yagi
J pole
5/8 wave vertical
Isotropic
91
Which of the following is used to determine if an antenna is resonant at the desired operating frequency?
An antenna analyzer
A Q meter
A VTVM
A frequency counter
92
What does an SWR reading of 4:1 indicate?
Impedance mismatch
Gain of +4 dB
Loss of -4 dB
Good impedance match
93
Which of the following are inputs to a satellite tracking program?
The Keplerian elements
The last observed time of zero Doppler shift
The satellite transmitted power
All these choices are correct
94
Which of the following is a resonant or tuned circuit?
An inductor and a capacitor in series or parallel
A resistor circuit used for reducing standing wave ratio
A circuit designed to provide high-fidelity audio
A linear voltage regulator
95
Which term describes the ability of a receiver to discriminate between multiple signals?
Selectivity
Discrimination ratio
Sensitivity
Harmonic distortion
96
What operating activity involves contacting as many stations as possible during a specified period?
Simulated emergency exercises
Public service events
Net operations
Contesting
97
Why is coaxial cable the most common feed line for amateur radio antenna systems?
It can handle more power than any other type of feed line
It has less loss than any other type of feed line
It is easy to use and requires few special installation considerations
It is less expensive than any other type of feed line
98
What is a satellite beacon?
The primary transmit antenna on the satellite
A reflective surface on the satellite
An indicator light that shows where to point your antenna
A transmission from a satellite that contains status information
99
What is the impact of using excessive effective radiated power on a satellite uplink?
Overloading the satellite batteries
Possibility of commanding the satellite to an improper mode
Blocking access by other users
Possibility of rebooting the satellite control computer
100
What is the approximate length; in inches; of a quarter-wavelength vertical antenna for 146 MHz?
12
112
19
50
101
Which of the following can reduce overload of a VHF transceiver by a nearby commercial FM station?
Using double-shielded coaxial cable
Installing a band-reject filter
Installing an RF preamplifier
Installing bypass capacitors on the microphone cable
102
Which of the following is used to convert a signal from one frequency to another?
Amplifier
Phase splitter
Mixer
Inverter
103
What should be done to all external ground rods or earth connections?
Keep them as far apart as possible
Bond them together with heavy wire or conductive strap
Tune them for resonance on the lowest frequency of operation
Waterproof them with silicone caulk or electrical tape
104
What reading indicates that an ohmmeter is connected across a large; discharged capacitor?
Alternating between open and short circuit
Increasing resistance with time
Steady full-scale reading
Decreasing resistance with time
105
Which type of voice mode is often used for long-distance (weak signal) contacts on the VHF and UHF bands?
DRM
PM
SSB
FM
106
When configured to measure current; how is a multimeter connected to a component?
In quadrature
In series
In parallel
In phase
107
In the United States; what circuit does black wire insulation indicate in a three-wire 120 V cable?
Neutral
Hot
Equipment ground
Black insulation is never used
108
Which of the following is a digital communications mode?
Packet radio
All these choices are correct
IEEE 802.11
FT8
109
Which of the following methods is used to locate sources of noise interference or jamming?
Phase locking
Doppler radar
Radio direction finding
Echolocation
110
Where is an RF preamplifier installed?
At the output of the transmitter power amplifier
Between the antenna and receiver
Between the transmitter and the antenna tuner
At the output of the receiver audio amplifier
111
What is an advantage of a 5/8 wavelength whip antenna for VHF or UHF mobile service?
It radiates at a very high angle
It has more gain than a 1/4-wavelength antenna
It has 10 times the power gain of a 1/4 wavelength whip
It eliminates distortion caused by reflected signals
112
What is a disadvantage of air core coaxial cable when compared to foam or solid dielectric types?
It cannot be used for VHF or UHF antennas
It cannot be used at below freezing temperatures
It requires special techniques to prevent moisture in the cable
It has more loss per foot
113
What is the name of a circuit that generates a signal at a specific frequency?
Low-pass filter
Reactance modulator
Phase modulator
Oscillator
114
What is the purpose of a fuse in an electrical circuit?
To remove power in case of overload
To limit current to prevent shocks
All these choices are correct
To prevent power supply ripple from damaging a component
115
What hazard is caused by charging or discharging a battery too quickly?
Inverse memory effect
Overheating or out-gassing
Half-wave rectification
Excess output ripple
116
Which of the following types of signal has the narrowest bandwidth?
Slow-scan TV
CW
SSB voice
FM voice
117
What is a beam antenna?
An omnidirectional antenna invented by Clarence Beam
An antenna that reverses the phase of received signals
An antenna built from aluminum I-beams
An antenna that concentrates signals in one direction
118
What is the electrical difference between RG-58 and RG-213 coaxial cable?
There is no significant difference between the two types
RG-213 cable has less loss at a given frequency
RG-58 cable has two shields
RG-58 cable can handle higher power levels
119
What type of transmission is indicated by the term "NTSC?"
A special mode for satellite uplink
An analog fast-scan color TV signal
A frame compression scheme for TV signals
A Normal Transmission mode in Static Circuit

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