T8 - Modulation modes [4 Exam Questions - 4 Groups] Flashcards Preview

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Flashcards in T8 - Modulation modes [4 Exam Questions - 4 Groups] Deck (46)
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1
Q

Which of the following is a form of amplitude modulation?

A. Spread-spectrum

B. Packet radio

C. Single sideband

D. Phase shift keying

A

C. Single sideband

2
Q

What type of modulation is most commonly used for VHF packet radio transmissions?

A. FM

B. SSB

C. AM

D. Spread Spectrum

A

A. FM

3
Q

Which type of voice mode is most often used for long-distance (weak signal) contacts on the VHF and UHF bands?

A. FM

B. DRM

C. SSB

D. PM

A

C. SSB

4
Q

Which type of modulation is most commonly used for VHF and UHF voice repeaters?

A. AM

B. SSB

C. PSK

D. FM

A

D. FM

5
Q

Which of the following types of emission has the narrowest bandwidth?

A. FM voice

B. SSB voice

C. CW

D. Slow-scan TV

A

C. CW

6
Q

Which sideband is normally used for 10 meter HF, VHF and UHF single-sideband communications?

A. Upper sideband

B. Lower sideband

C. Suppressed sideband

D. Inverted sideband

A

A. Upper sideband

7
Q

What is the primary advantage of single sideband over FM for voice transmissions?

A. SSB signals are easier to tune

B. SSB signals are less susceptible to interference

C. SSB signals have narrower bandwidth

D. All of these choices are correct

A

C. SSB signals have narrower bandwidth

8
Q

What is the approximate bandwidth of a single sideband voice signal?

A. 1 kHz

B. 3 kHz

C. 6 kHz

D. 15 kHz

A

B. 3 kHz

9
Q

What is the approximate bandwidth of a VHF repeater FM phone signal?

A. Less than 500 Hz

B. About 150 kHz

C. Between 10 and 15 kHz

D. Between 50 and 125 kHz

A

C. Between 10 and 15 kHz

10
Q

What is the typical bandwidth of analog fast-scan TV transmissions on the 70 cm band?

A. More than 10 MHz

B. About 6 MHz

C. About 3 MHz

D. About 1 MHz

A

B. About 6 MHz

11
Q

What is the approximate maximum bandwidth required to transmit a CW signal?

A. 2.4 kHz

B. 150 Hz

C. 1000 Hz

D. 15 kHz

A

B. 150 Hz

12
Q

Who may be the control operator of a station communicating through an amateur satellite or space station?

A. Only an Amateur Extra Class operator

B. A General Class licensee or higher licensee who has a satellite operator certification

C. Only an Amateur Extra Class operator who is also an AMSAT member

D. Any amateur whose license privileges allow them to transmit on the satellite uplink frequency

A

D. Any amateur whose license privileges allow them to transmit on the satellite uplink frequency

13
Q

How much transmitter power should be used on the uplink frequency of an amateur satellite or space station?

A. The maximum power of your transmitter

B. The minimum amount of power needed to complete the contact

C. No more than half the rating of your linear amplifier

D. Never more than 1 watt

A

B. The minimum amount of power needed to complete the contact

14
Q

Which of the following are provided by satellite tracking programs?

A. Maps showing the real-time position of the satellite track over the earth

B. The time, azimuth, and elevation of the start, maximum altitude, and end of a pass

C. The apparent frequency of the satellite transmission, including effects of Doppler shift

D. All of these answers are correct

A

D. All of these answers are correct

15
Q

Which amateur stations may make contact with an amateur station on the International Space Station using 2 meter and 70 cm band amateur radio frequencies?

A. Only members of amateur radio clubs at NASA facilities

B. Any amateur holding a Technician or higher class license

C. Only the astronaut’s family members who are hams

D. You cannot talk to the ISS on amateur radio frequencies

A

B. Any amateur holding a Technician or higher class license

16
Q

What is a satellite beacon?

A. The primary transmit antenna on the satellite

B. An indicator light that that shows where to point your antenna

C. A reflective surface on the satellite

D. A transmission from a space station that contains information about a satellite

A

D. A transmission from a space station that contains information about a satellite

17
Q

Which of the following are inputs to a satellite tracking program?

A. The weight of the satellite

B. The Keplerian elements

C. The last observed time of zero Doppler shift

D. All of these answers are correct

A

B. The Keplerian elements

18
Q

With regard to satellite communications, what is Doppler shift?

A. A change in the satellite orbit

B. A mode where the satellite receives signals on one band and transmits on another

C. An observed change in signal frequency caused by relative motion between the satellite and the earth station

D. A special digital communications mode for some satellites

A

C. An observed change in signal frequency caused by relative motion between the satellite and the earth station

19
Q

What is meant by the statement that a satellite is operating in mode U/V?

A. The satellite uplink is in the 15 meter band and the downlink is in the 10 meter band

B. The satellite uplink is in the 70 cm band and the downlink is in the 2 meter band

C. The satellite operates using ultraviolet frequencies

D. The satellite frequencies are usually variable

A

B. The satellite uplink is in the 70 cm band and the downlink is in the 2 meter band

20
Q

What causes spin fading when referring to satellite signals?

A. Circular polarized noise interference radiated from the sun

B. Rotation of the satellite and its antennas

C. Doppler shift of the received signal

D. Interfering signals within the satellite uplink band

A

B. Rotation of the satellite and its antennas

21
Q

What do the initials LEO tell you about an amateur satellite?

A. The satellite battery is in Low Energy Operation mode

B. The satellite is performing a Lunar Ejection Orbit maneuver

C. The satellite is in a Low Earth Orbit

D. The satellite uses Light Emitting Optics

A

C. The satellite is in a Low Earth Orbit

22
Q

What is a commonly used method of sending signals to and from a digital satellite?

A. USB AFSK

B. PSK31

C. FM Packet

D. WSJT

A

C. FM Packet

23
Q

Which of the following methods is used to locate sources of noise interference or jamming?

A. Echolocation

B. Doppler radar

C. Radio direction finding

D. Phase locking

A

C. Radio direction finding

24
Q

Which of these items would be useful for a hidden transmitter hunt?

A. Calibrated SWR meter

B. A directional antenna

C. A calibrated noise bridge

D. All of these choices are correct

A

B. A directional antenna

25
Q

What popular operating activity involves contacting as many stations as possible during a specified period of time?

A. Contesting

B. Net operations

C. Public service events

D. Simulated emergency exercises

A

A. Contesting

26
Q

Which of the following is good procedure when contacting another station in a radio contest?

A. Be sure to sign only the last two letters of your call if there is a pileup calling the station

B. Work the station twice to be sure that you are in his log

C. Send only the minimum information needed for proper identification and the contest exchange

D. All of these choices are correct

A

C. Send only the minimum information needed for proper identification and the contest exchange

27
Q

What is a grid locator?

A. A letter-number designator assigned to a geographic location

B. A letter-number designator assigned to an azimuth and elevation

C. An instrument for neutralizing a final amplifier

D. An instrument for radio direction finding

A

A. A letter-number designator assigned to a geographic location

28
Q

How is access to an IRLP node accomplished?

A. By obtaining a password which is sent via voice to the node

B. By using DTMF signals

C. By entering the proper Internet password

D. By using CTCSS tone codes

A

B. By using DTMF signals

29
Q

What is the maximum power allowed when transmitting telecommand signals to radio controlled models?

A. 500 milliwatts

B. 1 watt

C. 25 watts

D. 1500 watts

A

B. 1 watt

30
Q

What is required in place of on-air station identification when sending signals to a radio control model using amateur frequencies?

A. Voice identification must be transmitted every 10 minutes

B. Morse code ID must be sent once per hour

C. A label indicating the licensee�s name, call sign and address must be affixed to the transmitter

D. A flag must be affixed to the transmitter antenna with the station call sign in 1 inch high letters or larger

A

C. A label indicating the licensee�s name, call sign and address must be affixed to the transmitter

31
Q

How might you obtain a list of active nodes that use VoIP?

A. From the FCC Rulebook

B. From your local emergency coordinator

C. From a repeater directory

D. From the local repeater frequency coordinator

A

C. From a repeater directory

32
Q

How do you select a specific IRLP node when using a portable transceiver?

A. Choose a specific CTCSS tone

B. Choose the correct DSC tone

C. Access the repeater autopatch

D. Use the keypad to transmit the IRLP node ID

A

D. Use the keypad to transmit the IRLP node ID

33
Q

What name is given to an amateur radio station that is used to connect other amateur stations to the Internet?

A. A gateway

B. A repeater

C. A digipeater

D. A beacon

A

A. A gateway

34
Q

What is meant by Voice Over Internet Protocol (VoIP) as used in amateur radio?

A. A set of rules specifying how to identify your station when linked over the Internet to another station

B. A set of guidelines for working DX during contests using Internet access

C. A technique for measuring the modulation quality of a transmitter using remote sites monitored via the Internet

D. A method of delivering voice communications over the Internet using digital techniques

A

D. A method of delivering voice communications over the Internet using digital techniques

35
Q

What is the Internet Radio Linking Project (IRLP)?

A. A technique to connect amateur radio systems, such as repeaters, via the Internet using Voice Over Internet Protocol

B. A system for providing access to websites via amateur radio

C. A system for informing amateurs in real time of the frequency of active DX stations

D. A technique for measuring signal strength of an amateur transmitter via the Internet

A

A. A technique to connect amateur radio systems, such as repeaters, via the Internet using Voice Over Internet Protocol

36
Q

Which of the following is an example of a digital communications method?

A. Packet

B. PSK31

C. MFSK

D. All of these choices are correct

A

D. All of these choices are correct

37
Q

What does the term �APRS� mean?

A. Automatic Packet Reporting System

B. Associated Public Radio Station

C. Auto Planning Radio Set-up

D. Advanced Polar Radio System

A

A. Automatic Packet Reporting System

38
Q

Which of the following devices provides data to the transmitter when sending automatic position reports from a mobile amateur radio station?

A. The vehicle speedometer

B. A WWV receiver

C. A connection to a broadcast FM sub-carrier receiver

D. A Global Positioning System receiver

A

D. A Global Positioning System receiver

39
Q

What type of transmission is indicated by the term NTSC?

A. A Normal Transmission mode in Static Circuit

B. A special mode for earth satellite uplink

C. An analog fast scan color TV signal

D. A frame compression scheme for TV signals

A

C. An analog fast scan color TV signal

40
Q

Which of the following is an application of APRS (Automatic Packet Reporting System)?

A. Providing real time tactical digital communications in conjunction with a map showing the locations of stations

B. Showing automatically the number of packets transmitted via PACTOR during a specific time interval

C. Providing voice over Internet connection between repeaters

D. Providing information on the number of stations signed into a repeater

A

A. Providing real time tactical digital communications in conjunction with a map showing the locations of stations

41
Q

What does the abbreviation PSK mean?

A. Pulse Shift Keying

B. Phase Shift Keying

C. Packet Short Keying

D. Phased Slide Keying

A

B. Phase Shift Keying

42
Q

What is PSK31?

A. A high-rate data transmission mode

B. A method of reducing noise interference to FM signals

C. A method of compressing digital television signals

D. A low-rate data transmission mode

A

D. A low-rate data transmission mode

43
Q

Which of the following may be included in packet transmissions?

A. A check sum which permits error detection

B. A header which contains the call sign of the station to which the information is being sent

C. Automatic repeat request in case of error

D. All of these choices are correct

A

D. All of these choices are correct

44
Q

What code is used when sending CW in the amateur bands?

A. Baudot

B. Hamming

C. International Morse

D. Gray

A

C. International Morse

45
Q

Which of the following can be used to transmit CW in the amateur bands?

A. Straight Key

B. Electronic Keyer

C. Computer Keyboard

D. All of these choices are correct

A

D. All of these choices are correct

46
Q

What is an ARQ transmission system?

A. A special transmission format limited to video signals

B. A system used to encrypt command signals to an amateur radio satellite

C. A digital scheme whereby the receiving station detects errors and sends a request to the sending station to retransmit the information

D. A method of compressing the data in a message so more information can be sent in a shorter time

A

C. A digital scheme whereby the receiving station detects errors and sends a request to the sending station to retransmit the information