Technicians Exam-Operating Modes

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rledwith
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Technicians Exam-Operating Modes
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Amateur Radio Technicians Exam - T8 Operating Modes
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  1. T8A01 Which of the following is a form of amplitude modulation?
    A. Spread-spectrum
    B. Packet radio
    C. Single sideband
    D. Phase shift keying
    • C. Single sideband
    • An amplitude modulation (AM) signal consists of a carrier and two sidebands; one higher in frequency than the carrier (the upper sideband, USB) and one lower (the lower sideband, LSB). A single-sideband (SSB) signal is created by removing the carrier and one of the sidebands. [Ham Radio License Manual, page 2-8]
  2. T8A02 What type of modulation is most commonly used for VHF packet radio transmissions?
    A. FM
    B. SSB
    C. AM
    D. Spread Spectrum
    • A. FM
    • FM can be used for data signals, such as those for packet radio on VHF and UHF. The data is sent as audio tones by using the FM transmitter voice input and speaker output. This allows inexpensive FM voice radios to be used. [Ham Radio License Manual, page 2-10]
  3. T8A03 Which type of voice modulation is most often used for long-distance or weak signal contacts onthe VHF and UHF bands?
    A. FM
    B. AM
    C. SSB
    D. PM
    • C. SSB
    • Because the SSB signal’s power is concentrated into a narrow bandwidth, it is possible to communicate with SSB over much longer ranges and in poorer conditions than with FM or AM, particularly on the VHF and UHF bands. That is why the VHF and UHF DXers and contest operators use SSB signals. [Ham Radio License Manual, page 2-10]
  4. T8A04 Which type of modulation is most commonly used for VHF and UHF voice repeaters?
    A. AM
    B. SSB
    C. PSK
    D. FM
    • D. FM
    • Frequency modulation (FM) and its close relative phase modulation (PM) are used in repeater communication because of the mode’s superior rejection of noise and static. [Ham Radio License Manual, pages 2-10, 3-18]
  5. T8A05 Which of the following types of emission has the narrowest bandwidth?
    A. FM voice
    B. SSB voice
    C. CW
    D. Slow-scan TV
    • C. CW
    • CW signals consist of a continuous wave signal on a single frequency that is turned on and off in the patterns that make up the Morse code. As a result, CW has the narrowest bandwidth of any mode copied directly by the human ear. [Ham Radio License Manual, page 2-10]
  6. T8A06 Which sideband is normally used for 10 meter HF, VHF and UHF single-sidebandcommunications?
    A. Upper sideband
    B. Lower sideband
    C. Suppressed sideband
    D. Inverted sideband
    • A. Upper sideband
    • There is no technical reason for choosing USB over LSB. However, in order to make communications easier, amateur radio has standardized on the following conventions: • Below 10 MHz, LSB is used • Above 10 MHz, USB is used — including all of the VHF and UHF bands This convention is even programmed into radio equipment as the normal operating mode! There is one exception: amateurs are required to use USB on the five 60 meter band (5 MHz) channels. [Ham Radio License Manual, page 2-10]
  7. T8A07 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
    • C. SSB signals have narrower bandwidth
    • Whereas an FM signal may have a bandwidth of 5 to 15 kHz, SSB signals only require 2 to 3 kHz of spectrum. This increases the usable range of SSB signals compared to FM signals of equal power. (See question T8A03) [Ham Radio License Manual, page 2-10] *T8A03 - Because the SSB signal’s power is concentrated into a narrow bandwidth, it is possible to communicate with SSB over much longer ranges and in poorer conditions than with FM or AM, particularly on the VHF and UHF bands. That is why the VHF and UHF DXers and contest operators use SSB signals. [Ham Radio License Manual, page 2-10]
  8. T8A08 What is the approximate bandwidth of a single sideband voice signal?
    A. 1 kHz
    B. 3 kHz
    C. 6 kHz
    D. 15 kHz
    • B. 3 kHz
    • See the following table of Signal Bandwidths for various modes. [Ham Radio License Manual, page 2-10]
  9. T8A09 What is the approximate bandwidth of a VHF repeater FM phone signal?
    A. Less than 500 Hz
    B. About 150 kHz
    C. Between 5 and 15 kHz
    D. Between 50 and 125 kHz
    • C. Between 5 and 15 kHz
  10. T8A10 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
    • B. About 6 MHz
    • Note — On June 12, 2009 US broadcasters converted all over -the-air TV signals to digital modulation. Within the 6 MHz channel, there may be from four to five digitally-compressed audio-video programs, each  with a I .2-1 .5 MHz bandwidth. Amateurs Will continue to use the older analog format for fast-scan television for the for the foreseeable future and the bandwidth of those signals is approximately 6 MHz.
  11. T8A11 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
    • B. 150 Hz
    • Note — On June 12, 2009 US broadcasters converted all over -the-air TV signals to digital modulation. Within the 6 MHz channel, there may be from four to five digitally-compressed audio-video programs, each  with a I .2-1 .5 MHz bandwidth. Amateurs Will continue to use the older analog format for fast-scan television for the for the foreseeable future and the bandwidth of those signals is approximately 6 MHz
  12. T8B01 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
    • D. Any amateur whose license privileges allow them to transmit on the satellite uplink frequency
    • [97.209 (a)] — The control operator of a station communicating through an amateur satellite may hold any class of amateur license that has privileges to transmit in the satellite’s input frequency range, regardless of the frequency of the satellite's downlink signal. [Ham Radio License Manual, page 6-32]
  13. T8B02 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
    • B. The minimum amount of power needed to complete the contact
    • Using minimum power is particularly important when using satellites because of their very limited power sources. By transmitting with excessive power, you can actually cause the signals of other stations using the satellite to be reduced as they are relayed by the satellite. [Ham Radio License Manual, page 6-33]
  14. T8B03 Which of the following can be done using an amateur radio satellite?
    A. Talk to amateur radio operators in other countries
    B. Get global positioning information
    C. Make telephone calls
    D. All of these choices are correct
    • A. Talk to amateur radio operators in other countries
    • Because the satellite is high above the Earth, its transmitted signal can often be heard in many countries at the same time. The satellites farthest from Earth can provide coverage over nearly half of the Earth’s surface! [Ham Radio License Manual, page 6-32]
  15. T8B04 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
    • B. Any amateur holding a Technician or higher class license
    • The astronaut-amateurs on board the ISS operate according to the same FCC Rules that earthbound hams do, so there is no reason that communications between them should be restricted based on license class. Any amateur with a license that permits communications on the VHF frequencies used by the ISS is welcome to make contact! [Ham Radio License Manual, page 6-32]
  16. T8B05 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
    • D. A transmission from a space station that contains information about a satellite
    • Like its terrestrial counterparts, a satellite’s beacon transmits communications so that propagation to the satellite and information about the satellite can be observed. Receiving the beacon from a satellite indicates that it is within range and contacts with it or through it can be attempted. [Ham Radio License Manual, page 6-32]
  17. T8B06 What can be used to determine the time period during which an amateur satellite or space station can be accessed?
    A. A GPS receiver
    B. A field strength meter
    C. A telescope
    D. A satellite tracking program
    • D. A satellite tracking program
    • Satellites are typically only visible for short periods at a time, called a pass, because they are moving so rapidly. A computer can perform the calculations required to tell when a particular satellite is visible from your location by using a satellite-tracking program. The program uses mathematical coordinates called Keplerian elements available from online Web sites. The output of the program tells you when and where to look in the sky for the satellite. [Ham Radio License Manual, page 6-33]
  18. T8B07 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
    • C. An observed change in signal frequency caused by the relative motion between the satellite and the earth station
    • Doppler shift or Doppler effect describes the way the downlink frequency of a satellite varies by several kilohertz during an orbit due to its motion relative to the receiving station. As the satellite is moving toward the receiving station, the frequency of the satellite’s signal will increase by a small amount. After the satellite passes overhead, the frequency of the signal will begin to decrease. This is the same effect that causes the sound of a vehicle’s horn or whistle to change pitch as it moves past you. [Ham Radio License Manual, page 6-32]
  19. T8B08 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
    • B. The satellite uplink is in the 70 cm band and the downlink is in the 2 meter band
    • The satellite’s operational mode specifies the bands on which it is transmitting and receiving. Most satellites only have one mode, but some have several that can be controlled by ground stations. Mode is specified as two letters separated by a slash. The first letter indicates the uplink band and the second letter indicates the downlink band. For example, the uplink for a satellite in U/V mode is in the UHF band (70 cm) and a downlink in the VHF band (2 meters). [Ham Radio License Manual, page 6-33]
  20. T8B09 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
    • B. Rotation of the satellite and its antennas
    • Most satellites spin to stabilize their orientation in space. Spin fading is caused by rotation of the satellite and its antennas with respect to the receiving station. As the satellite spins, it’s signal will strengthen and weaken depending on the orientation of the antennas. [Ham Radio License Manual, page 6-33]
  21. T8B10 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
    • C. The satellite is in a Low Earth Orbit
    • Low Earth Orbit is the term for satellites orbiting up to about 1600 miles above the Earth, including the International Space Station. LEO satellites have nearly circular orbits and are only visible from Earth for a few minutes. Higher orbits are referred to as Medium Earth Orbit. Farthest out are the Geosynchronous Earth Orbit satellites, whose orbital period matches exactly the rotation of the Earth so that the satellite appears to stay above one spot on Earth. [Ham Radio License Manual, page 6-33]
  22. T8B11 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
    • C. FM Packet
    • The “Pacsats” are satellites equipped with FM packet radio stations. These satellites can operate as digipeaters and sometimes as bulletin board stations. [Ham Radio License Manual, page 6-33]
  23. T8C01 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
    • C. Radio direction finding
    • There are a number of techniques that allow a radio operator to determine the bearing to a radio transmitter. Using them is called direction finding. Exercises in which hams try to find a hidden transmitter are also called foxhunts or bunny hunts. In recent years a new type of outdoor radiosport has reached US shores from Europe and Asia — radio direction finding or RDF. Held as organized events, direction finding is a hybrid of the radio fox hunt using orienteering skills to navigate outdoors with map and compass. The US Amateur Radio Direction Finding organization (www.ardfusa.com) is just one of a number of national groups in this worldwide sport, especially popular with teens and young adults. If you are a hiker or camper, then you might be interested in applying your outdoor skills to ARDF. [Ham Radio License Manual, page 6-31]
  24. T8C02 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
    • B. A directional antenna
    • You don’t need much in the way of equipment. A portable radio with a signal strength indicator and a handheld or portable directional antenna, such as a small Yagi beam, will work just fine. The point of the exercise is to determine direction to a radio source, the hidden transmitter, and to do so requires a directional antenna. [Ham Radio License Manual, page 6-31]
  25. T8C03 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. Contesting
    • A radio contest or radiosport event consists of making as many contacts as you can with stations in a targeted area or on specific bands. Contests last for only a few hours or maybe all weekend. They’re a great way to improve your station capabilities and operating skills. See the ARRL Web site for an event calendar and links to contest rules. [Ham Radio License Manual, page 6-30]
  26. T8C04 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
    • C. Send only the minimum information needed for proper identification and the contest exchange
    • Check the contest rules and listen to a few contacts during the contest to find out what information is required in the contest exchange. [Ham Radio License Manual, page 6-30]
  27. T8C05 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 letter-number designator assigned to a geographic location
    • The Maidenhead Locator System (named after the city in England where it was developed) divides the Earth’s surface into grids organized by latitude and longitude. The designator for each grid square consists of two letter and two numbers, such as CN87 or FM13.For example, ARRL Headquarters in Newington, Connecticut is located in grid square FN31. A further two letters can be added for greater precision, such as FN31pq for the precise location of the ARRL station. (Learn more about grid squares at the ARRL Web site.) [Ham Radio License Manual, page 6-4]
  28. T8C06 For what purpose is a temporary “1 by 1” format (letter-number-letter) call sign assigned?
    A. To designate an experimental station
    B. To honor a deceased relative who was a radio amateur
    C. For operations in conjunction with an activity of special significance to the amateur community
    D. All of these choices are correct
    • C. For operations in conjunction with an activity of special significance to the amateur community
    • Any FCC-licensed amateur or club can also obtain a special 1×1 (1-by-1) call sign such as W3X or K6P for a short-duration special event of significance to the amateur community. These call signs are special because they only have one letter in both the prefix and suffix. Special event call signs are very popular and contacts with them are sought out by hams, worldwide. [Ham Radio License Manual, page 7-21]
  29. T8C07 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
    • B. 1 watt
    • Amateurs may transmit telecommand signals with an output power of up to 1 watt. Although the signals do not identify the licensee on the air, radio control (RC) modelers are required to display their name, call sign and address on the RC transmitter. [Ham Radio License Manual, page 6-35]
  30. T8C08 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
    • C. A label indicating the licensee’s name, call sign and address must be affixed to the transmitter
    • Amateurs may transmit telecommand signals with an output power of up to 1 watt. Although the signals do not identify the licensee on the air, radio control (RC) modelers are required to display their name, call sign and address on the RC transmitter. [Ham Radio License Manual, page 6-35]
  31. T8C09 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
    • C. From a repeater directory
    • Both the IRLP and EchoLink systems maintain an Internet directory of repeaters participating in their systems. You can browse the directories to find nodes (repeaters and Internet voice server systems) currently on the air. [Ham Radio License Manual, page 6-20]
  32. T8C10 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
    • D. Use the keypad to transmit the IRLP node ID
    • To initiate an IRLP or Echolink contact, the initiating station must know the repeater control code to request an IRLP connection — this is the ON code. The ON code varies from repeater to repeater and obtaining it may require membership in a club. Once the ON code is entered via your keypad, the four-digit code for the IRLP node — a destination repeater — is entered. The code then directs the repeater controller to establish the Internet link to the desired node. [Ham Radio License Manual, page 6-20]
  33. T8C11 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 gateway
    • An Internet gateway is a special kind of digital station that provides a connection to the Internet for data transmitted by Amateur Radio from other station. Most gateways are set up to forward messages. The most common examples are packet radio bulletin board systems (BBS) and the Winlink RMS stations. Messages with a recognized Internet email address can be sent and retrieved over these systems. Another type of gateway provides direct Internet connectivity so that a computer running standard Web browser software can connect to any Internet address. [Ham Radio License Manual, page 5-12]
  34. T8D01 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
    • D. All of these choices are correct
    • Packet radio uses a version of the computer-to-computer X.25 data exchange protocol that was adapted to suit amateur use becoming the AX.25 protocol. PSK31 is an abbreviation for phase-shift keying at 31 baud for low-rate keyboard-to-keyboard communications in a narrow bandwidth. MFSK uses frequency-shift keying of multiple carriers for data communications. Packet radio is generally used on VHF and UHF frequencies while PSK31 and MFSK are primarily used on the HF bands. [Ham Radio License Manual, page 5-8]
  35. T8D02 What does the term APRS mean?
    A. Automatic Position Reporting System
    B. Associated Public Radio Station
    C. Auto Planning Radio Set-up
    D. Advanced Polar Radio System
    • A. Automatic Position Reporting System
    • The Automatic Position Reporting System (APRS) was created by WB4APR as a way of transmitting GPS location information over Amateur Radio using a system of digipeaters. These relay points forward the position information and call sign to a system of server computers via the Internet. Once the information is stored on the servers Web sites can access the data and show the position of the station on maps in various ways. [Ham Radio License Manual, page 5-10]
  36. T8D03 Which of the following is normally used when sending automatic location reports via amateur radio?
    A. A connection to the vehicle speedometer
    B. A WWV receiver
    C. A connection to a broadcast FM sub-carrier receiver
    D. A Global Positioning System receiver
    • D. A Global Positioning System receiver
    • The Automatic Position Reporting System (APRS) was created by WB4APR as a way of transmitting GPS location information over Amateur Radio using a system of digipeaters. These relay points forward the position information and call sign to a system of server computers via the Internet. Once the information is stored on the servers Web sites can access the data and show the position of the station on maps in various ways. [Ham Radio License Manual, page 5-10]
  37. T8D04 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
    • C. An analog fast scan color TV signal
    • NTSC stands for the National Television System Committee, which developed the standards that define broadcast fast-scan analog television signals. (For many years, broadcast TV stations in the United States used the NTSC standard for their analog TV broadcasts before they converted to a digital TV signal standard in 2009.) Amateurs adopted the NTSC standard for amateur television (ATV) transmissions. RS-170 is the standard that describes fast-scan video signals before they are sent over the air. These signals can be received on a commercial analog TV receiver equipped with a suitable frequency converter to tune amateur frequencies. The ARRL Image Communications Handbook and Technical Information Service pages on the ARRL Web site provide more information on ATV. [Ham Radio License Manual, page 6-34]
  38. T8D05 Which of the following emission modes may be used by a Technician Class operator between 219 and 220 MHz?
    A. Spread spectrum
    B. Data
    C. SSB voice
    D. Fast-scan television
    • B. Data
    • 219-220 MHz is a mode-restricted sub-band restricted to digital message forwarding only for amateurs of all license classes. Only point-to-point digital message forwarding is allowed between 219 MHz and 220 MHz. Amateurs have access to these frequencies as a secondary allocation, and a number of restrictions apply, as described in Part 97.303(e). Check the FCC Rules [97.305(c)] for limitations on other bands before you begin operations. [Ham Radio License Manual, page 7-13]
  39. T8D06 What does the abbreviation PSK mean?
    A. Pulse Shift Keying
    B. Phase Shift Keying
    C. Packet Short Keying
    D. Phased Slide Keying
    • B. Phase Shift Keying
    • In phase-shift keying (PSK), the phase of a signal is varied in order to convey information. Amateurs use PSK of an audio signal to transmit information. The audio signal can be transmitted as an AM or FM signal. [Ham Radio License Manual, page 5-9]
  40. T8D07 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 signal
    D. A low-rate data transmission mode
    • D. A low-rate data transmission mode
    • Packet radio uses a version of the computer-to-computer X.25 data exchange protocol that was adapted to suit amateur use becoming the AX.25 protocol. PSK31 is an abbreviation for phase-shift keying at 31 baud for low-rate keyboard-to-keyboard communications in a narrow bandwidth. MFSK uses frequency-shift keying of multiple carriers for data communications. Packet radio is generally used on VHF and UHF frequencies while PSK31 and MFSK are primarily used on the HF bands. [Ham Radio License Manual, page 5-8]
  41. T8D08 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
    • D. All of these choices are correct
    • Packet radio sends data in bursts called packets. Each packet consists of a header and data. The header contains information about the packet and the call sign of the destination station. The header also includes a checksum that allows the receiver to detect errors. If an error is detected, the receiver automatically requests that the packet be retransmitted until the data is received properly. This is called ARQ for automatic repeat request. [Ham Radio License Manual, page 5-9]
  42. T8D09 What code is used when sending CW in the amateur bands?
    A. Baudot
    B. Hamming
    C. International Morse
    D. Gray
    • C. International Morse
    • Amateurs use the International Morse code for CW transmissions. [Ham Radio License Manual, page 5-8]
  43. T8D10 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
    • D. All of these choices are correct
    • For sending Morse code, a key is used to turn the transmitter output signal on and off. Morse code’s dots and dashes are known as the elements of the code. When using a straight key, the operator generates the dots and dashes manually. This is called hand keying. The J-38 is a common type of straight key and is popular with beginners. Once you are skilled at “the code,” you’ll want to go faster by using a keyer. This electronic device turns contact closures from a Morse paddle into a stream of Morse code elements. A keyer may be a standalone device or it can be built in to a transceiver. A paddle is a pair of levers mounted side by side, each having its own set of contacts, one for dots and one for dashes. Keyers and paddles can generate Morse code much faster than by using a straight key. Computer software can also send CW directly from the keyboard by using a keying interface connected to the key input of a radio. [Ham Radio License Manual, page 5-5]
  44. T8D11 What is a “parity” bit?
    A. A control code required for automatic position reporting
    B. A timing bit used to ensure equal sharing of a frequency
    C. An extra code element used to detect errors in received data
    D. A “triple width” bit used to signal the end of a character
    • C. An extra code element used to detect errors in received data
    • Some digital codes include extra data elements to allow the receiver to detect an error. The parity bit is used to tell the receiver whether the number of “1” bits in the character was odd or even. If the received character does not agree with the parity bit, the character can be discarded or a retransmission can be requested. [Ham Radio License Manual, page 5-8]

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