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 is a disadvantage of air core coaxial cable when compared to foam or solid dielectric types?

It requires special techniques to prevent moisture in the cable

What causes spin fading of satellite signals?

Rotation of the satellite and its antennas

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

Prevent loosening of the turnbuckle from vibration

Why is coaxial cable the most common feed line for amateur radio antenna systems?

It is easy to use and requires few special installation considerations

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

They are commonly used at HF and VHF frequencies

What telemetry information is typically transmitted by satellite beacons?

Health and status of the satellite

Which of the following is a resonant or tuned circuit?

An inductor and a capacitor in series or parallel

What is an advantage of a 5/8 wavelength whip antenna for VHF or UHF mobile service?

It has more gain than a 1/4-wavelength antenna

What is the electrical difference between RG-58 and RG-213 coaxial cable?

RG-213 cable has less loss at a given frequency

Where should a fuse or circuit breaker be installed in a 120V AC power circuit?

In series with the hot conductor only

What is a grid locator?

A letter-number designator assigned to a geographic location

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

Only one signal can be received at a time

What is the purpose of a fuse in an electrical circuit?

To remove power in case of overload

studbud

Test test part 2

119 termsStudBud Administration

Imported from external platform

Flashcards119 cardsFPractice quizPHost liveL

Questions 119

Answers

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

Test test part 2 Flashcards | StudBud