Technician Licensing Class MultiMode Radio Excitement Valid July

Technician Licensing Class Multi-Mode Radio Excitement Valid July 1, 2018 Through June 30, 2022 1

Amateur Radio Technician Class Element 2 Course Presentation Ø ELEMENT 2 SUB-ELEMENTS (Groupings) • • • About Ham Radio Call Signs Control Mind the Rules Tech Frequencies Your First Radio Going Solo Repeaters Emergency! Weak Signal Propagation 2

Amateur Radio Technician Class Element 2 Course Presentation Ø ELEMENT 2 SUB-ELEMENTS (Groupings) • Talk to Outer Space! • Your Computer Goes Ham Digital! Ø Multi-Mode Radio Excitement • Run Some Interference Protection • Electrons – Go With the Flow! • It’s the Law, per Mr. Ohm! • Go Picture These! • Antennas • Feed Me With Some Good Coax! • Safety First! 3

Multi-Mode Radio Excitement • A transceiver is a unit combining the functions of a transmitter and receiver. T 7 A 02 4

Multi-Mode Radio Excitement • SSB (single sideband) is the voice mode most often used for long-distance (weak signal) contacts on the VHF and UHF bands. T 8 A 03 5

Multi-Mode Radio Excitement • The primary advantage of single sideband over FM for voice transmissions is SSB signals have narrower bandwidth. T 8 A 07 6

Multi-Mode Radio Excitement • The SSB/CW-FM switch on a VHF power amplifier sets the amplifier for properation in the selected mode. T 7 A 09 • Single sideband (SSB) is a form of amplitude modulation. T 8 A 01 7

Multi-Mode Radio Excitement • Upper sideband (USB) is normally used for 10 meter HF, VHF and UHF single-sideband communications. as our communications mode. T 8 A 06 • Modulation describes combining speech with an RF carrier signal. T 7 A 08 Amplitude-modulated signal 8

Multi-Mode Radio Excitement • 3 k. Hz is the approximate bandwidth of a single sideband voice signal. T 8 A 08 9

Multi-Mode Radio Excitement • 2400 Hz is an appropriate receive filter bandwidth to select in order to minimize noise and interference for SSB reception. T 4 B 09 10

Multi-Mode Radio Excitement • The use of SSB phone is permitted in at least some portion of all the bands above 50 MHz. • The receiver RIT or clarifier controls could be used if the voice pitch of a single-sideband signal seems too high or low. • “RIT” means Receiver Incremental Tuning. T 2 B 13 T 4 B 06 T 4 B 07 11

Multi-Mode Radio Excitement • The name of a circuit that generates a signal of a desired frequency is called an oscillator. T 7 A 05 • Of FM, SSB, CW and Slow-scan TV CW is the emission that has the narrowest bandwidth. 12 T 8 A 05

Multi-Mode Radio Excitement • 150 Hz is the approximate maximum bandwidth required to transmit a CW signal. T 8 A 11 • 500 Hz is an appropriate receive filter bandwidth to select in order to minimize noise and interference for CW reception. T 4 B 10 13

Multi-Mode Radio Excitement • The advantage of having multiple receive bandwidth choices on a multimode transceiver is that it permits noise or interference reduction by selecting a bandwidth matching the mode. T 4 B 08 14

Multi-Mode Radio Excitement • Sensitivity is the term that describes the ability of a receiver to detect the presence of a signal. T 7 A 01 15

Multi-Mode Radio Excitement • A mixer is used to convert a radio signal from one frequency to another. T 7 A 03 Station Signal C at 455 k. Hz Signal A at 800 k. Hz (or at 1200 k. Hz) Intermediate Frequency Local Oscillator Signal B at 1255 k. Hz (or at 1655 k. Hz) 16

Multi-Mode Radio Excitement • The term that describes the ability of a receiver to discriminate between multiple signals is called selectivity. T 7 A 04 17

Multi-Mode Radio Excitement • The function of automatic gain control or AGC is to keep received audio relatively constant. T 4 B 11 • The RF preamplifier is installed between the antenna and the receiver. T 7 A 11 18

Multi-Mode Radio Excitement • A transverter converts the RF input and output of a transceiver to another band. T 7 A 06 • DMR (Digital Mobile Radio) is a technique for timemultiplexing two digital voice signals on a single 12. 5 k. Hz repeater channel. T 8 D 07 19

Multi-Mode Radio Excitement • A DMR repeater “talk group” is a way for groups of users to share a channel at different times without being heard by other users on the channel. T 2 B 09 • To join a digital repeater’s “talk group” you must program your radio with the group’s ID or code. T 2 B 07 20

Multi-Mode Radio Excitement • Broadband-Hamnet (also referred to as high-speed multimedia network) is an amateur-radio-based data network using commercial Wi-Fi gear with modified firmware. T 8 D 12 21

Element 2 Technician Class Question Pool Multi-Mode Radio Excitement Valid July 1, 2018 Through June 30, 2022 22

T 7 A 02 What is a transceiver? A. A type of antenna switch B. A unit combining the functions of a transmitter and receiver C. A component in a repeater which filters out unwanted interference D. A type of antenna matching network 23

T 8 A 03 Which type of voice mode is most often used for long-distance (weak signal) contacts on the VHF and UHF bands ? A. B. C. D. FM DRM SSB PM 24

T 8 A 07 What is an advantage of single sideband (SSB) over FM for voice transmissions? A. B. C. D. SSB signals are easier to tune SSB signals are less susceptible to interference SSB signals have narrower bandwidth All of these choices are correct 25

T 7 A 09 What is the function of the SSB/CW-FM switch on a VHF power amplifier? A. Change the mode of the transmitted signal B. Set the amplifier for properation in the selected mode C. Change the frequency range of the amplifier to operate in the proper portion of the band D. Reduce the received signal noise 26

T 8 A 01 Which of the following is a form of amplitude modulation? A. B. C. D. Spread-spectrum Packet radio Single sideband Phase shift keying 27

T 8 A 06 Which sideband is normally used for 10 meter HF, VHF and UHF single-sideband communications? A. B. C. D. Upper sideband Lower sideband Suppressed sideband Inverted sideband 28

T 7 A 08 Which of the following describes combining speech with an RF carrier signal? A. B. C. D. Impedance matching Oscillation Modulation Low-pass filtering 29

T 8 A 08 What is the approximate bandwidth of a single sideband voice signal? A. B. C. D. 1 k. Hz 3 k. Hz 6 k. Hz 15 k. Hz 30

T 4 B 09 Which of the following is an appropriate receive filter bandwidth to select in order to minimize noise and interference for SSB reception? A. B. C. D. 500 Hz 1000 Hz 2400 Hz 5000 Hz 31

T 2 B 13 Where may SSB phone be used in amateur bands above 50 MHz? A. Only in sub-bands allocated to General class or higher licensees B. Only on repeaters C. In at least some portion of all these bands D. On any band as long as power is limited to 25 watts 32

T 4 B 06 Which of the following controls could be used if the voice pitch of a single-sideband signal seems too high or low? A. B. C. D. The AGC or limiter The bandwidth selection The tone squelch The receiver RIT or clarifier 33

T 4 B 07 What does the term "RIT" mean? A. B. C. D. Receiver Input Tone Receiver Incremental Tuning Rectifier Inverter Test Remote Input Transmitter 34

T 7 A 05 What is the name of a circuit that generates a signal of a desired frequency? A. B. C. D. Reactance modulator Product detector Low-pass filter Oscillator 35

T 8 A 05 Which of the following types of emission has the narrowest bandwidth? A. B. C. D. FM voice SSB voice CW Slow-scan TV 36

T 8 A 11 What is the approximate maximum bandwidth required to transmit a CW signal? A. B. C. D. 2. 4 k. Hz 150 Hz 1000 Hz 15 k. Hz 37

T 4 B 10 Which of the following is an appropriate receive filter bandwidth to select in order to minimize noise and interference for CW reception? A. B. C. D. 500 Hz 1000 Hz 2400 Hz 5000 Hz 38

T 4 B 08 What is the advantage of having multiple receive bandwidth choices on a multimode transceiver? A. Permits monitoring several modes at once B. Permits noise or interference reduction by selecting a bandwidth matching the mode C. Increases the number of frequencies that can be stored in memory D. Increases the amount of offset between receive and transmit frequencies 39

T 7 A 01 Which term describes the ability of a receiver to detect the presence of a signal? A. B. C. D. Linearity Sensitivity Selectivity Total Harmonic Distortion 40

T 7 A 03 Which of the following is used to convert a radio signal from one frequency to another? A. B. C. D. Phase splitter Mixer Inverter Amplifier 41

T 7 A 04 Which term describes the ability of a receiver to discriminate between multiple signals? A. B. C. D. Discrimination ratio Sensitivity Selectivity Harmonic Distortion 42

T 4 B 11 What is the function of automatic gain control or AGC? A. B. C. D. To keep received audio relatively constant To protect an antenna from lightning To eliminate RF on the station cabling asymmetric goniometer control used for antenna matching 43

T 7 A 11 Where is an RF preamplifier installed? A. Between the antenna and the receiver B. At the output of the transmitter’s power amplifier C. Between transmitter and antenna tuner D. At the receiver’s audio output 44

T 7 A 06 What device converts the RF input and output of a transceiver to another band? A. B. C. D. High-pass filter Low-pass filter Transverter Phase converter 45

T 8 D 07 Which of the following best describes DMR (Digital Mobile Radio)? A. A technique for time-multiplexing two digital voice signals on a single 12. 5 k. Hz repeater channel B. An automatic position tracking mode for FM mobiles communicating through repeaters C. An automatic computer logging technique for hands -off logging when communicating while operating a vehicle D. A digital technique for transmitting on two repeater inputs simultaneously for automatic error correction 46

T 2 B 09 What is a “talk group” on a DMR digital repeater? A. A group of operators sharing common interests B. A way for groups of users to share a channel at different times without being heard by other users on the channel C. A protocol that increases the signal-to-noise ratio when multiple repeaters are linked together D. A net that meets at a particular time 47

T 2 B 07 How can you join a digital repeater’s “talk group”? A. Register your radio with the local FCC office B. Join the repeater owner’s club C. Program your radio with the group’s ID or code D. Sign your call after the courtesy tone 48

T 8 D 12 Which of the following best describes Broadband-Hamnet(TM), also referred to as a high-speed multi-media network? A. An amateur-radio-based data network using commercial Wi-Fi gear with modified firmware B. A wide-bandwidth digital voice mode employing DRM protocols C. A satellite communications network using modified commercial satellite TV hardware D. An internet linking protocol used to network repeaters 49