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Technician Licensing Class These Power Point presentations are available to individuals who register with Technician Licensing Class These Power Point presentations are available to individuals who register with The W 5 YI Group’s Ham. Instructor. com program. The presentations are provided by Master Publishing and The W 5 YI Group and include material that is covered by U. S. and International copyrights. They are intended solely for the use of Registered Instructors using the Gordon West, WB 6 NOA, Technician Class, General Class, and Extra Class study manuals to teach FCC Amateur Radio Licensing Classes. Registration through Ham. Instructor. com constitutes a Licensing Agreement between The W 5 YI Group and the registered instructor under which the instructor agrees not to copy or distribute the Power Point presentations to unauthorized users. 1

Technician Licensing Class Multi-Mode Radio Excitement Valid July 1, 2014 Through June 30, 2018 Technician Licensing Class Multi-Mode Radio Excitement Valid July 1, 2014 Through June 30, 2018 2

Amateur Radio Technician Class Element 2 Course Presentation Ø ELEMENT 2 SUB-ELEMENTS (Groupings) • 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 3

Amateur Radio Technician Class Element 2 Course Presentation Ø ELEMENT 2 SUB-ELEMENTS (Groupings) • 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! 4

Multi-Mode Radio Excitement • T 7 A 02 For convenience, compactness, and economy, most Multi-Mode Radio Excitement • T 7 A 02 For convenience, compactness, and economy, most modern amateur radio equipment comes in the form of a “transceiver, ” which combines both transmitting and receiving functions in one package. However, many experienced radio amateurs prefer the performance and versatility of separate transmitters and receivers (also known as “separates” or “twins”), where the vastly different functions of transmitting and receiving can be thoroughly optimized. In addition, many radio amateurs enjoy using vintage or “boat anchor” radios, built when the concept of combining both transmitters and receivers in one cabinet was unheard of. In fact, many manufacturers during the Golden Age of ham radio built only transmitters or receivers, and the typical ham was compelled to put together his station from a variety of specialized sources, or build his own. Count yourself lucky to be a radio amateur now! 5

Multi-Mode Radio Excitement 6 Multi-Mode Radio Excitement 6

Multi-Mode Radio Excitement • T 7 A 09 Your Technician Class license puts you Multi-Mode Radio Excitement • T 7 A 09 Your Technician Class license puts you in the mainstream of exciting, 2 -meter and 440 -MHz operation. You can bounce signals off of the moon with your Technician Class license, and talk with stations hundreds of miles away off of meteor trails. Perhaps work the amateur satellites, or try sending signals thousands of miles within atmospheric temperature inversions. This excitement is available to you as a Technician operator, but you need more than just a simple FM transceiver. Look for a multi -mode VHF transceiver to get started on the 2 -meter band, using CW and upper sideband for weak signal work. There is also a satellite weak signal “window” between 145. 800 to 146. 000 MHz. It takes a multi-mode radio on CW and SSB to work weak signal VHF activities. 7

Multi-Mode Radio Excitement 8 Multi-Mode Radio Excitement 8

Multi-Mode Radio Excitement • T 8 A 03 Unlike the common FM mode that Multi-Mode Radio Excitement • T 8 A 03 Unlike the common FM mode that you will be using with your dual-band handheld, single sideband (SSB) requires special – yet not too expensive – equipment, and 6 -meter single-sideband radios are seen regularly at swap meets. Six-meter SSB signals are ideal for bouncing off the ionosphere. And, as you will hear on the enclosed audio CD, it is mighty exciting! • T 8 A 07 We use frequency modulation through FM repeaters on many popular VHF and UHF ham bands. But near the bottom of 6 meters, 2 meters, 1 1/4 meters, and at 432 and 1296 MHz, we use single sideband, which uses less bandwidth than FM signals. 9

Multi-Mode Radio Excitement 10 Multi-Mode Radio Excitement 10

Multi-Mode Radio Excitement • T 8 A 01 A form of amplitude modulation is Multi-Mode Radio Excitement • T 8 A 01 A form of amplitude modulation is called single sideband (SSB). With a single-sideband signal, the amplitude of the radio wave rises with the spoken word, up to a limit of around 2. 8 k. Hz. Some hams employ double sideband, so the radio wave both rises and dips occupying almost twice as much bandwidth as single sideband. Single sideband is the type of modulation we use for weak-signal VHF and UHF work on Technician Class frequencies. 11

Multi-Mode Radio Excitement • T 8 A 06 On VHF and UHF, we always Multi-Mode Radio Excitement • T 8 A 06 On VHF and UHF, we always use upper sideband as our communications mode. Single sideband is an advanced feature after you have been on the air for a few months as a Technician Class operator. You won’t find single sideband capability in a ham handheld. You will find SSB in all worldwide high frequency radio sets. This equipment may also give you 6 meters, 2 meters, and 70 cm, in addition to the worldwide HF capability. We don’t use single sideband through repeaters. SSB is found at the bottom of most VHF/UHF ham bands, so you will want to try the following frequencies – all upper sideband – to hear some SSB signals: 10 meters 28. 400 MHz SSB 6 meters 50. 125 MHz SSB 2 meters 144. 200 MHz SSB 70 cm 432. 100 MHz SSB No FM allowed on these weak-signal SSB frequencies. Worldwide equipment, which includes all of these bands plus HF, costs less than $1, 000. 12

Multi-Mode Radio Excitement 13 Multi-Mode Radio Excitement 13

Multi-Mode Radio Excitement • T 7 A 08 Modulation is the process of applying Multi-Mode Radio Excitement • T 7 A 08 Modulation is the process of applying information (voice, video, or digital) onto a radio signal. The information modifies some characteristic of the radio frequency carrier, so that the information may be transmitted through the air. Inside that brand new dual-band handheld is a circuit called the modulator. It converts your spoken word going into the microphone into an electrical speech signal that is combined with the RF carrier. The modulator is always on the transmit side of your equipment, tied in to the microphone. 14

Multi-Mode Radio Excitement • T 8 A 08 The properly-adjusted single sideband transmitter on Multi-Mode Radio Excitement • T 8 A 08 The properly-adjusted single sideband transmitter on VHF and UHF frequencies for Technician Class operators occupies approximately 2 to 3 k. Hz of bandwidth, depending on your voice characteristics. We employ upper sideband for VHF and UHF weak-signal work. Be sure to listen to the audio CD included with this book for the sounds of SSB. 15

Multi-Mode Radio Excitement • T 4 B 09 For single sideband, the normal voice Multi-Mode Radio Excitement • T 4 B 09 For single sideband, the normal voice bandwidth is about 2500 Hz, so the 2400 Hz bandwidth selection would be the appropriate filter. This usually happens automatically, so you don’t need to do a thing to enjoy weak signal work! • T 2 B 13 As a new Technician, you will want to explore all that’s available to you, and weak signal SSB (or CW!) operation is permitted in at least some portion of all the amateur bands above 50 MHz. Multimode VHF transceivers are now plentiful and inexpensive. 16

Multi-Mode Radio Excitement • T 4 B 06 If you plan to do some Multi-Mode Radio Excitement • T 4 B 06 If you plan to do some weak signal work, great! We need more weak signal operators, using CW (Morse code) and single sideband. It will take a little practice to tune in voice properly on single sideband. You should set your receiver RIT or clarifier to the neutral position, and then adjust slightly the big tuning knob for proper SSB voice reception. You can then make fine tuning adjustments with the receiver RIT or clarifier. 17

Multi-Mode Radio Excitement • T 4 B 07 The “RIT” control is only found Multi-Mode Radio Excitement • T 4 B 07 The “RIT” control is only found on high-end, weak-signal, mobile and base station equipment capable of SSB. The Receiver Incremental Tuning control allows you to fine-tune the receiver slightly up and down about one kilohertz without changing your transmit frequency, which is useful for working satellite Doppler shift. For non-satellite work, leave the RIT disabled so you are always transmitting and receiving on your same frequency. 18

Multi-Mode Radio Excitement • T 4 A 01 When we speak into a microphone, Multi-Mode Radio Excitement • T 4 A 01 When we speak into a microphone, sound pressure waves strike an element which converts acoustic energy into electrical waves. The electrical waves then are sent along to the transmitter that will ultimately transmit electromagnetic (radio) waves onto the airwaves. Microphone jacks and power connections on handhelds as well as mobile equipment may look similar between different manufacturers, but they are not! Some mobile radio microphone jacks output a small DC voltage to power the microphone. Each manufacturer assigns this voltage to a specific pin, and if you accidentally plug in the wrong microphone, you could short the voltage to ground, zapping your radio instantly. It’s about a $125 fix! Always make sure the microphone, or custom Heil headset, has the correct adapter cable for your specific radio brand model number. There are many advantages to going with professional headsets, but make sure you order the correct adapter cable! 19

Multi-Mode Radio Excitement • T 7 A 05 All radio signals originate with an Multi-Mode Radio Excitement • T 7 A 05 All radio signals originate with an oscillator of some sort, somewhere in the circuitry. An oscillator is essentially an amplifier with positive feedback and some frequency-determining components, most frequently a resonant or tuned circuit. Oscillators come in countless varieties, using everything from vibrating quartz crystals to wobbling atoms as the resonant circuit. Some of the more classic oscillator circuits used in amateur radio are the Colpitts, the Hartley, and the Clapp oscillator. Various “multivibrator” circuits also function in an oscillator-like fashion in many digital circuits. 20

Multi-Mode Radio Excitement • T 8 A 05 The Federal Communications Commission may soon Multi-Mode Radio Excitement • T 8 A 05 The Federal Communications Commission may soon rule on the switch from restricted types of communications over to the more reasonable bandwidth limitations for amateur communications. FM voice and slow-scan TV use modest bandwidth; SSB voice has a “skinny” bandwidth, and the ultranarrowest bandwidth of all (of these answers) is Morse code, CW. Even though the code test for CW has been eliminated for all classes of ham licenses, CW will always be a popular, ultra-narrow -bandwidth way of communicating. 21

Multi-Mode Radio Excitement • T 8 A 11 I hope all of you will Multi-Mode Radio Excitement • T 8 A 11 I hope all of you will try some CW down on the worldwide portion of your Technician Class privileges on 80, 40, 15 and 10 meters. When you switch your multi-mode rig over to CW, you will see that the bandwidth narrows down. This minimizes the pickup of other CW signals off frequency. 150 Hz is just right. • T 4 B 10 For Morse code (CW), we restrict the bandwidth down to a skinny 400 Hz. Anything wider would bring in noise. Again, when you switch your worldwide radio to CW, the narrower 500 Hz bandwidth filter automatically clicks in. 22

Multi-Mode Radio Excitement • T 4 B 08 On 6 and 10 meters SSB Multi-Mode Radio Excitement • T 4 B 08 On 6 and 10 meters SSB and CW, the worldwide radio offers bandwidth choices. When you change modes, your radio will automatically tighten up or expand the internal bandwidth filter selection. This allows you to minimize noise and maximize long range reception. 23

Multi-Mode Radio Excitement • T 7 A 01 The ability of a receiver to Multi-Mode Radio Excitement • T 7 A 01 The ability of a receiver to detect a weak radio signal is known as sensitivity. For effective HF amateur radio operation, a receiver must have a power gain of approximately 10, 000: 1 (or about 70 decibels as measured at the antenna terminals) to bring a medium strength HF signal to a comfortable listening level with a set of earphones. As daunting as this task may seem, this sort of sensitivity is extremely easy to achieve with modern electronic components. In fact, a very primitive – but still popular – receiver known as a regenerative receiver can achieve this kind of performance with just a handful of components! Every ham should build a regenerative receiver sometime in his “career. ” Some of us have built lots of them! 24

Multi-Mode Radio Excitement • T 7 A 03 The mixer is a non-linear device Multi-Mode Radio Excitement • T 7 A 03 The mixer is a non-linear device that takes two signals injected into it and creates both the sums and the differences of any two radio signals. A simple diode can act as a mixer, but most modern day radios use a much more elegant arrangement using several diodes or active devices such as transistors or FETs to create a mixer circuit. Mixers are essential to nearly every modern radio design, and are crucial to the overall performance of the radio in most cases. 25

Multi-Mode Radio Excitement • T 7 A 04 The capability of any radio equipment Multi-Mode Radio Excitement • T 7 A 04 The capability of any radio equipment to specifically hear one frequency, and discriminate against signals on either side of that frequency, is called selectivity. On VHF and UHF equipment the selectivity is usually pre-set, and most equipment is plenty selective. On the worldwide radio gear, you can sometimes add more filters for increased selectivity. While additional filters may cut down on the fidelity of the received signal, you can “tighten up” on the receiver response. 26

Multi-Mode Radio Excitement • T 4 B 12 AGC, automatic gain control (formerly known Multi-Mode Radio Excitement • T 4 B 12 AGC, automatic gain control (formerly known as AVC, or automatic volume control), is used to somewhat level out the huge variations in signal strength a signal can undergo between a distant station on its way to you. The AGC bus is also used in most radios to drive the S-meter. AGC systems can range from rudimentary to extremely sophisticated, with varieties of attack time, decay time, “hang time” and other parameters, all for the purpose of making HF reception most effective over widely varying conditions. 27

Multi-Mode Radio Excitement • T 7 A 11 Don’t go out and buy one. Multi-Mode Radio Excitement • T 7 A 11 Don’t go out and buy one. Your radio equipment already has an excellent built-in preamplifier. Only if you purchased a very old radio, with noticeably weak reception, would you consider an external preamplifier. The pre-amp goes in between the antenna input and the receiver. Be careful how you wire it in – if you simply put it on the outside of the equipment, the first time you transmit, the pre-amp is history! It either needs external switching, or must be placed inside the equipment, between the antenna line and the receiver section. 28

Multi-Mode Radio Excitement • T 7 A 06 Many folks become ham radio operators Multi-Mode Radio Excitement • T 7 A 06 Many folks become ham radio operators from their experience on CB, 27 MHz. Some of their 27 MHz equipment may be modified and tied into a device called a “transverter, ” making the 11 meter signal now coming out on 222 MHz. To reverse this process, you will also need a receiving converter or downconverter, which takes a 220 MHz receive signal and downconverts it to the 27 or 28 MHz receiver “front end” frequency. While there are transverters which perform both functions in a single package, you can’t assume that all “transverters” work on the receive side. So, “caveat emptor” when purchasing – or better yet, build your own! Transverters are great beginning homebrew projects! So if you have some older CB radio, multimode, equipment don’t toss it just yet. You might be able to use it on ham frequencies with a transverter. 29

Multi-Mode Radio Excitement 30 Multi-Mode Radio Excitement 30

Multi-Mode Radio Excitement • T 4 A 03 Never try to run your 12 Multi-Mode Radio Excitement • T 4 A 03 Never try to run your 12 -volt equipment directly from a battery charger, or attempt to transmit with your handheld when it is plugged into the wall adaptor. If you plan to run your equipment off of commercial power with it still plugged in, always use a regulated power supply to protect your gear from voltage fluctuations. The regulated power supply plugs into the AC wall outlet, and then your radio plugs into the power supply. The greatest cause of handheld transmit hum, and sometimes damage to the equipment, is trying to transmit with it still plugged into the AC receptacle power adaptor. 31

Element 2 Technician Class Question Pool Multi-Mode Radio Excitement Valid July 1, 2014 Through Element 2 Technician Class Question Pool Multi-Mode Radio Excitement Valid July 1, 2014 Through June 30, 2018 32

T 7 A 02 What is a transceiver? A. A type of antenna switch 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 33

T 7 A 09 Which of the following devices is most useful for VHF T 7 A 09 Which of the following devices is most useful for VHF weak-signal communication? A. B. C. D. A quarter-wave vertical antenna A multi-mode VHF transceiver An omni-directional antenna A mobile VHF FM transceiver 34

T 8 A 03 Which type of voice mode is most often used for 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 35

T 8 A 07 What is the primary advantage of single sideband over FM T 8 A 07 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 36

T 8 A 01 Which of the following is a form of amplitude modulation? 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 37

T 8 A 06 Which sideband is normally used for 10 meter HF, VHF 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 38

T 7 A 08 Which of the following describes combining speech with an RF 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 39

T 8 A 08 What is the approximate bandwidth of a single sideband voice 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 40

T 4 B 09 Which of the following is an appropriate receive filter bandwidth 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 41

T 2 B 13 Which of the following is true of the use of T 2 B 13 Which of the following is true of the use of SSB phone in amateur bands above 50 MHz? A. It is permitted only by holders of a General Class or higher license B. It is permitted only on repeaters C. It is permitted in at least some portion of all the amateur bands above 50 MHz D. It is permitted only on when power is limited to no more than 100 watts 42

T 4 B 06 Which of the following controls could be used if the 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 43

T 4 B 07 What does the term 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 44

T 4 A 01 Which of the following is true concerning the microphone connectors T 4 A 01 Which of the following is true concerning the microphone connectors on amateur transceivers? A. All transceivers use the same microphone connector type B. Some connectors include push-to-talk and voltages for powering the microphone C. All transceivers using the same connector type are wired identically D. Un-keyed connectors allow any microphone to be connected 45

T 7 A 05 What is the name of a circuit that generates a 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 46

T 8 A 05 Which of the following types of emission has the narrowest 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 47

T 8 A 11 What is the approximate maximum bandwidth required to transmit a 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 48

T 4 B 10 Which of the following is an appropriate receive filter bandwidth 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 49

T 4 B 08 What is the advantage of having multiple receive bandwidth choices 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 50

T 7 A 01 Which term describes the ability of a receiver to detect 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 51

T 7 A 03 Which of the following is used to convert a radio 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 52

T 7 A 04 Which term describes the ability of a receiver to discriminate 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 53

T 4 B 12 What is the function of automatic gain control or AGC? T 4 B 12 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 54

T 7 A 11 Where is an RF preamplifier installed? A. Between the antenna 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 55

T 7 A 06 What device takes the output of a low-powered 28 MHz T 7 A 06 What device takes the output of a low-powered 28 MHz SSB exciter and produces a 222 MHz output signal? A. B. C. D. High-pass filter Low-pass filter Transverter Phase converter 56

T 4 A 03 Which is a good reason to use a regulated power T 4 A 03 Which is a good reason to use a regulated power supply for communications equipment? A. It prevents voltage fluctuations from reaching sensitive circuits B. A regulated power supply has FCC approval C. A fuse or circuit breaker regulates the power D. Power consumption is independent of load 57