Technician Test T8 to T0 questions Flashcards
1
Q
Which of the following is a form of amplitude modulation? T8A01
A
Single sideband
5-3
2
Q
What type of modulation is commonly used for VHF packet radio transmissions? T8A02
A
FM or PM
5-4
3
Q
Which type of voice mode is often used for long-distance (weak signal) contacts on the VHF and UHF bands? T8A03
A
SSB
5-4
4
Q
Which type of modulation is commonly used for VHF and UHF voice repeaters? T8A04
A
FM or PM
5-4
5
Q
Which of the following types of signal has the narrowest bandwidth? T8A05
A
CW
5-4
6
Q
Which sideband is normally used for 10 meter HF, VHF, and UHF single-sideband communications? T8A06
A
Upper sideband
5-4
7
Q
What is a characteristic of single sideband (SSB) compared to FM? T8A07
A
SSB signals have narrower bandwidth
5-4
8
Q
What is the approximate bandwidth of a typical single sideband (SSB) voice signal? T8A08
A
3 kHz
5-4
9
Q
What is the approximate bandwidth of a VHF repeater FM voice signal? T8A09
A
Between 10 and 15 kHz
5-4
10
Q
What is the approximate bandwidth of AM fast-scan TV transmissions? T8A10
A
About 6 MHz
5-4
11
Q
What is the approximate bandwidth required to transmit a CW signal? T8A11
A
150 Hz
5-4
12
Q
Which of the following is a disadvantage of FM compared with single sideband? T8A12
A
Only one signal can be received at a time
5-4
13
Q
What telemetry information is typically transmitted by satellite beacons? T8B01
A
Health and status of the satellite
6-24
14
Q
What is the impact of using excessive effective radiated power on a satellite uplink? T8B02
A
Blocking access by other users
15
Q
Which of the following are provided by satellite tracking programs? T8B03
A
All these choices are correct
-Maps showing the real-time position of the satellite track over earth
-The time, azimuth, and elevation of the start, maximum altitude and end of a pass
-The apparent frequency of the satellite transmission, including effects of Doppler shift
6-24
16
Q
What mode of transmission is commonly used by amateur radio satellites? T8B04
A
All these choices are correct
-SSB
-FM
-CW/data
6-24
17
Q
What is a satellite beacon? T8B05
A
A transmission from a satellite that contains status information
6-23
18
Q
Which of the following are inputs to a satellite tracking program? T8B06
A
The Keplerian elements
6-24
19
Q
What is Doppler shift in reference to satellite communications? T8B07
A
An observed change in signal frequency caused by relative motion between the satellite and Earth station
6-23
20
Q
What is meant by the statement that a satellite is operating in U/V mode? T8B08
A
The satellite uplink is in the 70 centimeter band and the downlink is in the 2 meter band
6-24
21
Q
What causes spin fading of satellite signals? T8B09
A
Rotation of the satellite and its antennas
6-23
22
Q
What is a LEO satellite? T8B10
A
A satellite in low earth orbit
6-23
23
Q
Who may receive telemetry from a space station? T8B11
A
Anyone
6-24
24
Q
Which of the following is a way to determine whether your satellite uplink power is neither too low nor too high? T8B12
A
Your signal strength on the downlink should be about the same as the beacon
6-24
25
Which of the following methods is used to locate sources of noise interference or jamming? T8C01
Radio direction finding
6-10
26
Which of these items would be useful for a hidden transmitter hunt? T8C02
A directional antenna
6-10
27
What operating activity involves contacting as many stations as possible during a specific period? T8C03
Contesting
6-7
28
Which of the following is good procedure when contacting another station in a contest? T8C04
Send only the minimum information needed for proper identification and the contest exchange
6-7
29
What is a grid locator? T8C05
A letter-number designator assigned to a geographic location
6-8
30
How is over the air access to IRLP nodes accomplished? T8C06
By using DTMF signals
6-13
31
What is Voice Over Internet Protocol (VoIP)? T8C07
A method of delivering voice communications over the internet using digital techniques
6-13
32
What is the Internet Radio Linking Project (IRLP)? T8C08
A technique to connect amateur radio systems, such as repeaters, via the internet using VoIP
6-13
33
Which of the following protocols enables an amateur station to transmit through a repeater without using a radio to initiate the transmission? T8C09
EchoLink
6-13
34
What is required before using EchoLink system? T8C10
Register your call sign and provide proof of license
6-13
35
What is an amateur radio station that connects other amateur stations to the internet? T8C11
A gateway
5-15
36
Which of the following is a digital communications mode? T8D01
All these choices are correct
-Packet radio
-IEEE 802.11
-FT8
5-11
37
What is a Talkgroup on a DMR repeater? T8D02
A way for groups of users to share a channel at different times without hearing other users on the channel
6-14
38
What kind of data can be transmitted by APRS? T8D03
All these choices are correct
-GPS position data
-Text messages
-Weather data
5-13
39
What type of transmission is indicated by the term "NTSC"? T8D04
An analog fast-scan color TV signal
6-9
40
Which of the following is an application of APRS? T8D05
Providing real-time tactical digital communications in conjunction with a map showing the locations of stations
5-13
41
What does the abbreviation "PSK" mean? T8D06
Phase Shift Keying
5-13
42
Which of the following describes DMR? T8D07
A technique for time-multiplexing two digital voice signals on a single 12.5 kHz repeater channel
6-14
43
Which of the following is included in packet radio transmissions? T8D08
All these choices are correct
-A check sum that permits error detection
-A header that contains the call sign of the station to which the information is being sent
-Automatic repeat request in case of error
5-12
44
What is CW? T8D09
Another name for Morse code transmission
5-2
45
Which of the following operating activities is supported by digital mode software in the WSJT-X software suite? T8D10
All these choices are correct
- Earth-Moon-Earth
-Weak signal propagation beacons
-Meteor scatter
5-12
46
What is an ARQ transmission system? T8D11
An error correction method in which the receiving station detects errors and sends a request for retransmission
5-12
47
Which of the following best describes an amateur radio mesh network? T8D12
An amateur-radio based data network using commercial Wi-Fi equipment with modified firmware
5-12
48
What is FT8? T8D13
A digital mode capable of low signal-to-noise operation
5-12
49
What is a beam antenna? T9A01
An antenna that concentrates signals in one direction
4-15
50
Which of the following describes a type of antenna loading? T9A02
Electrically lengthening by inserting inductors in radiating elements
4-12
51
Which of the following describes a simple dipole oriented parallel to Earth's surface? T9A03
A horizontally polarized antenna
4-12
52
What is a disadvantage of the short, flexible antenna supplied with most handheld radio transceivers, compared to full-sized quarter-wave antenna? T9A04
It has low efficiency
4-12
53
Which of the following increases the resonant frequency of a dipole antenna? T9A05
Shortening it
4-12
54
Which of the following types of antenna offers the greatest gain? T9A06
Yagi
4--15
55
What is a disadvantage of using a handheld VHF transceiver with a flexible antenna inside a vehicle? T9A07
Signal strength is reduced due to the shielding effect of the vehicle
4-12
56
What is the approximate length, in inches, of a quarter-wavelength vertical antenna for 146 MHz? T9A08
19
4-12
57
What is the approximate length, in inches, of a half wavelength 6 meter dipole antenna? T9A09
112
4-12
58
In which direction does a half-wave dipole antenna radiate the strongest signal? T9A10
Broadside to the antenna
4-12
59
What is antenna gain? T9A11
The increase in signal strength in a specified direction compared to a reference antenna
4-7
60
What is an advantage of a 5/8 wavelength whip antenna for VHF or UHF mobile service? T9A12
It has more gain than a 1/4 wavelength antenna
4-12
61
What is a benefit of low SWR? T9B01
Reduced signal loss
4-10
62
What is the most common impedance of coaxial cables used in amateur radio? T9B02
50 ohms
4-9
63
Why is coaxial cable the most common feed line for amateur radio antenna systems? T9B03
It is easy to use and requires few special installation considerations
4-9
64
What is the major function of an antenna tuner (antenna coupler)? T9B04
It matches the antenna system impedance to the transceiver's output impedance
4-18
65
What happens as the frequency of a signal in coaxial cable is increased? T9B05
The loss increases
4-9
66
Which of the following RF connector types is most suitable for frequencies above 400 MHz? T9B06
Type N
67
Which of the following is true of PL-259 type coax connectors? T9B07
They are commonly used at HF and VHF frequencies
4-17
68
Which of the following is a source of loss in coaxial feed line? T9B08
All these choices are correct
-Water intrusion into coaxial connectors
-High SWR
-Multiple connectors in the line
4-17
69
What can cause erratic changes in SWR? T9B09
Loose connection in the antenna or feed line
4-10
70
What is the electrical difference between Rg-58 and RG-213 coaxial cable? T9B10
RG213 cable has less loss at a given frequency
4-17
71
Which of the following types of feed line has the lowest loss at VHF and UHF? T9B11
Air-insulated hardline
4-17
72
What is standing wave ratio (SWR)? T9B12
A measure of how well a load is matched to a transmission line
4-9
73
Which of the following is a safety hazard of 12-volt storage batter? T0A01
Shorting the terminals can cause burns, fire or an explosion
9-2
74
What health hazard is presented by electrical current flowing through the body? T0A02
All these choices are correct
-It may cause injury by heating tissue
-It may disrupt the electrical functions of cells
-It may cause involuntary muscle contractions
9-2
75
In the United State, what circuit does black wire insulation indicate in a three-wire 120 V cable? T0A03
Hot
9-4
76
What is the purpose of a fuse in an electrical circuit? T0A04
To remove power in case of overload
3-12
77
Why should a 5-ampere fuse never be replaced with a 20-ampere fuse? T0A05
Excessive current could cause a fire
3-12
78
What is a good way to guard against electrical shock at your station? T0A06
All these choices are correct
-Use three wire cords and plugs for all AC powered equipment
-Connect all AC powered station equipment to a common safety ground
Install mechanical interlocks in high voltage circuits
9-4
79
Where should a lightning arrester be installed in a coaxial feed line? T0A07
On a ground panel near where feed lines enter the building
9-5
80
Where should a fuse or circuit breaker be installed in a 120V AC power circuit? T0A08
In series with the hot conductor only
9-4
81
What should be done to all external ground rods or earth connections? T0A09
Bond them together with heavy wire or conductive strap
9-5
82
What hazard is caused by charging or discharging a battery too quickly? T0A10
Overheating or out-gassing
5-17
83
What hazard exists in a power supply immediately after turning it off? T0A11
Charge stored in filter capacitors
9-2
84
Which of the following precautions should be taken when measuring high voltages with a voltmeter? T0A12
Ensure that the voltmeter and leads are rated for use at the voltages to be measured
3-4
85
Which of the following is good practice when installing ground wires on a tower for lightning protection? T0B01
Ensure that connections are short and direct
9-5
86
What is required when climbing an antenna tower? T0B02
All these choices are correct
-Have sufficient training on safe tower climbing techniques
-Use appropriate tie-off to the tower at all times
-Always wear an approved climbing harness
9-19
87
Under what circumstances is it safe to climb a tower without a helper or observer? T0B03
Never
9-19
88
Which of the following is an important safety precaution to observe when putting up an antenna tower? T0B04
Look for and stay clear of any overhead electrical wires
9-17
89
What is the purpose of a safety wire through a turnbuckle used to tension guy lines? T0B05
Prevent loosening of the turnbuckle from vibration
9-17
90
What is the minimum safe distance from a power line to allow when installing an antenna? T0B06
Enough so that if the antenna falls, no part of it can come closer than 10 feet to the power wires
9-17
91
Which of the following is an important safety rule to remember when using a crank-up tower? T0B07
This type of tower must not be climbed unless it is retracted, or mechanical safety locking devices have been installed
9-19
92
Which is a proper grounding method for a tower? T0B08
Separate eight foot ground rods for each tower leg, bonded to the tower and each other
9-17
93
Why should you avoid attaching an antenna to a utility pole? T0B09
The antenna could contact high-voltage power lines
9-17
94
Which of the following is true when installing grounding conductors used for lightning protection? T0B10
Sharp bends must be avoided
9-5
95
Which of the following establishes grounding requirements for an amateur radio tower or antenna? T0B11
Local electrical codes
9-5
96
What type of radiation are radio signals? T0C01
Non-ionizing radiation
9-11
97
At which of the following frequencies does maximum permissible exposure have the lowest value? T0C02
50 MHz
9-12
98
How does the allowable power density for RF safely change if duty cycle changes from 100 percent to 50 percent? T0C03
It increases by a factor of 2
9-13
99
What factors affect the RF exposure of people near an amateur station antenna? T0C04
All these choices are correct
-Frequency and power level of the RF field
-Distance from the antenna to a person
-Radiation pattern of the antenna
9-14
100
Why do exposure limits vary with frequency? T0C05
The human body absorbs more RF energy at some frequencies than others
9-11
101
Which of the following is an acceptable method to determine whether your station complies with FCC RF exposure regulations? T0C06
All these choices are correct
-By calculation based on FCC OET Bulletin 65
-By calculation based on computer modeling
-By measurement of field strength using calibrated equipment
9-14
102
What hazard is created by touching an antenna during a transmission? T0C07
RF burn to skin
9-11
103
Which of the following actions can reduce exposure to RF radiation? T0C08
Relocate antennas
9-11
104
How can you make sure your station stays in compliance with RF safety regulations? T0C09
By re-evaluating the station whenever an item in the transmitter or antenna system is changed
9-14
105
Why is duty cycle one of the factors used to determine safe RF radiation exposure levels? T0C10
It affects the average exposure to radiation
9-13
106
What is the definition of duty cycle during the averaging time for RF exposure? T0C11
The percentage of time that a transmitter is transmitting
9-13
107
How does RF radiation differ from ionizing radiation (radioactivity)? T0C12
RF radiation does not have sufficient energy to cause chemical changes in cells and damage DNA
9-11
108
Who is responsible for ensuring that no person is exposed to RF energy above the FCC exposure limits? T0C13
The station licensee
9-11
