Technician License Class Chapter 1 Welcome to Amateur Radio
What is Amateur Radio? Amateur (or Ham) Radio is a personal radio service authorized by the Federal Communications Commission (FCC).
What is Amateur Radio? According to the FCC, the purpose of Amateur Radio is: To encourage the advancement of the art and science of radio. To promote the development of an emergency communication capability to assist communities when needed. To develop a pool of trained radio operators. To promote international good will by connecting private citizens in countries around the globe.
What is Amateur Radio? Through ham radio, you will become an ambassador for your community and your country.
What is Amateur Radio? Who Can be a Ham? US citizen Alien No age limit Not representative of foreign government No age limit Must pass written examination
What is Amateur Radio? What Makes Amateur Radio Different? There are many unlicensed radio services Ham radio is licensed Fewer restrictions More frequencies (channels or bands to utilize) More power (to improve range and quality) More ways to communicate
What is Amateur Radio? More Privileges More Responsibility Because ham radios are much more capable and have the potential of interfering with other radio services. Because ham radios have unlimited reach. They easily reach around the globe and into space.
The FCC and Licensing FCC authorization is required to ensure the operator is qualified to operate the ham radio safely, appropriately, and within the rules and regulations – that is why you are here.
The FCC and Licensing The FCC has different rules and regulations for each type of radio service The Amateur Radio Service is governed by Part 97 of the FCC Rules and Regulations
The FCC and Licensing Prior to 1984, the FCC administered all amateur radio examinations In 1984 the Volunteer Examiner system was inaugurated Teams or 3 or more VE’s 14 VEC’s NCVEC
Amateur Radio Activities Identification and Contacts Every amateur in the world is issued a unique call sign Call sign identifies country In the USA, call signs begin with AA-AL, K, N, or W
Amateur Radio Activities Identification and Contacts In the USA, call sign may indicate what part of country
Amateur Radio Activities Identification and Contacts In the USA, call sign may indicate class of license Group Definition A 1x2 (1st letter K, N, or W) 2x1 (1st two letters AA-AL) 2x2 (1st two letters AA-AL) B 2x2 (1st letter K, N, or W) C 1x3 (1st letter K, N, or W) D 2x3 (1st letter K or W) Class Groups Amateur Extra A, B, C, or D Advanced B, C, or D General C, or D Technician Novice D
Amateur Radio Activities Identification and Contacts Any over-the-air conversation is called a “contact”. Contacts can be made using Voice Morse code Digital Television Satellites, meteor scatter, EME, etc.
Amateur Radio Activities Identification and Contacts Types of contacts include: Rag-chewing Public Service Contests DX Awards
Getting Your Ham Radio License Operator License Classes Technician Entry-level Privileges focused on local communications General Privileges include more long-distance communications capabilities Amateur Extra All amateur privileges
Getting Your Ham Radio License Testing Process Test sessions coordinated by a Volunteer Examiner Coordinator (VEC) FCC recognizes 14 VEC’s Individual VEC’s may or may not charge a test fee ARRL = $15 W5YI = $14 Laurel VEC = No test fee Team of at least 3 Volunteer Examiners (VE’s) required to administer exam
Getting Your Ham Radio License Examination Structure Exam questions taken from a published question pool. Technician question pool 426 multiple-choice questions 35 groups 1 question from each group Answer order will be scrambled
Break
Technician License Class Chapter 2 Radio Signals & Fundamentals
Metric Units Most of the time we will be using metric units. Need to be familiar with several of the metric prefixes & how to convert between them.
Metric Units
T5B01 -- How many milliamperes is 1.5 amperes?
T5B02 -- What is another way to specify a radio signal frequency of 1,500,000 hertz? 1500 kHz 1500 MHz 15 GHz 150 kHz
T5B03 -- How many volts are equal to one kilovolt? One one-thousandth of a volt One hundred volts One thousand volts One million volts
T5B04 -- How many volts are equal to one microvolt? One one-millionth of a volt One million volts One thousand kilovolts One one-thousandth of a volt
T5B05 -- Which of the following is equivalent to 500 milliwatts?
0.003 amperes 0.3 amperes 3 amperes 3,000,000 amperes T5B06 -- If an ammeter calibrated in amperes is used to measure a 3000-milliampere current, what reading would it show? 0.003 amperes 0.3 amperes 3 amperes 3,000,000 amperes
T5B07 -- If a frequency readout calibrated in megahertz shows a reading of 3.525 MHz, what would it show if it were calibrated in kilohertz? 0.003525 kHz 35.25 kHz 3525 kHz 3,525,000 kHz
T5B08 -- How many microfarads are 1,000,000 picofarads?
T5B12 -- Which of the following frequencies is equal to 28,400 kHz? 28.400 MHz 2.800 MHz 284.00 MHz 28.400 kHz
T5B13 -- If a frequency readout shows a reading of 2425 MHz, what frequency is that in GHz?
Radio Signals & Waves Radio waves (electromagnetic radiation) are AC waves. Created by an electrical signal that rapidly changes direction. a.k.a. – Radio signal. Travel at the speed of light. Radio waves are used to carry the information you want to convey to someone else.
Radio Signals & Waves Turning electrical signal into a radio wave is called radiating or radiation. Not the same as radioactive radiation. Radio equipment is designed to manipulate radio signals.
Radio Signals & Waves Before we study radio waves, we need to learn some wave vocabulary. Amplitude Frequency Period Wavelength Harmonics
Radio Signals & Waves Frequency Radio signals are AC signals. Rapidly reverse polarity & back again. Rate at which polarity changes is called “frequency”. Measured in Hertz (Hz). 1 Hz = 1 complete cycle per second The range of frequencies that produces radio signals is referred to as “RF”.
Radio Signals & Waves Phase Signals at the same frequency that cross zero at exactly the same time are “in phase”.
Radio Signals & Waves Radio Frequency (RF) Spectrum The RF spectrum is the range of wave frequencies which will leave an antenna and travel through space. The RF spectrum is divided into segments of frequencies that basically have unique behavior.
Radio Signals & Waves Radio Frequency (RF) Spectrum
Radio Signals & Waves Radio Frequency (RF) Spectrum
Radio Signals & Waves Wavelength The distance a radio wave travels during one cycle.
300 fMHz λm Radio Signals & Waves Wavelength Frequency (MHz) = 300 / Wavelength (meters) Wavelength (meters) = 300 / Frequency (MHz)
Radio Signals & Waves The RF spectrum is divided into “bands”. Bands are named by their approximate wavelength. 40m Band = 7.000 MHz to 7.300 MHz 20m Band = 14.000 MHz to 14.350 MHz 15m Band = 21.000 MHz to 21.450 MHz 10m Band = 28.000 MHz to 29.700 MHz 2m Band = 144 MHz to 148 MHz
Wave speed Waveform Wavelength Wave spread T3B01 -- What is the name for the distance a radio wave travels during one complete cycle? Wave speed Waveform Wavelength Wave spread
T3B04 -- How fast does a radio wave travel through free space? At the speed of light At the speed of sound Its speed is inversely proportional to its wavelength Its speed increases as the frequency increases
The wavelength gets longer as the frequency increases T3B05 -- How does the wavelength of a radio wave relate to its frequency? The wavelength gets longer as the frequency increases The wavelength gets shorter as the frequency increases There is no relationship between wavelength and frequency The wavelength depends on the bandwidth of the signal
Wavelength in meters equals frequency in hertz multiplied by 300 T3B06 -- What is the formula for converting frequency to approximate wavelength in meters? Wavelength in meters equals frequency in hertz multiplied by 300 Wavelength in meters equals frequency in hertz divided by 300 Wavelength in meters equals frequency in megahertz divided by 300 Wavelength in meters equals 300 divided by frequency in megahertz
The approximate wavelength The magnetic intensity of waves T3B07 -- What property of radio waves is often used to identify the different frequency bands? The approximate wavelength The magnetic intensity of waves The time it takes for waves to travel one mile The voltage standing wave ratio of waves
T3B08 -- What are the frequency limits of the VHF spectrum? 30 to 300 kHz 30 to 300 MHz 300 to 3000 kHz 300 to 3000 MHz
T3B09 -- What are the frequency limits of the UHF spectrum? 30 to 300 kHz 30 to 300 MHz 300 to 3000 kHz 300 to 3000 MHz
T3B10 -- What frequency range is referred to as HF? 300 to 3000 MHz 30 to 300 MHz 3 to 30 MHz 300 to 3000 kHz
3000 kilometers per second 300,000,000 meters per second T3B11 -- What is the approximate velocity of a radio wave as it travels through free space? 3000 kilometers per second 300,000,000 meters per second 300,000 miles per hour 186,000 miles per hour
Pulse rate Speed Wavelength Frequency T5A12 -- What term describes the number of times per second that an alternating current reverses direction? Pulse rate Speed Wavelength Frequency
T5C05 -- What is the unit of frequency? Hertz Henry Farad Tesla
T5C06 -- What does the abbreviation “RF” refer to? Radio frequency signals of all types The resonant frequency of a tuned circuit The real frequency transmitted as opposed to the apparent frequency Reflective force in antenna transmission lines
Modulation A constant-strength radio signal on a single frequency is called a “continuous wave”. A continuous wave (CW) is not very useful for communications. Must add information to the radio signal to use it for communicating. Adding information is called “modulation”.
Modulation Any characteristic of the signal can be changed to add the information. Amplitude Frequency Phase Retrieving the information from the signal is called “demodulation” or “detection”.
Modulation Different type of modulation are called “modes”. Simplest method is to merely turn the signal on and off in a particular pattern, such as Morse code. This mode is known as “CW”. Changing the strength (or amplitude) of the signal is known as amplitude modulation (AM). Changing the frequency of the signal is known as frequency modulation (FM). Under FM, mention phase modulation (PM).
CW – Morse Code
Amplitude Modulation In AM, the amplitude of the carrier wave is modified in step with the waveform of the information (voice).
Modulation Amplitude Modulation AM signals consist of three components: Carrier Lower sideband Upper sideband Voice bandwidth is from 300 Hz to 3 kHz. AM bandwidth is twice the voice bandwidth.
Modulation Amplitude Modulation The sound waves that make up your voice are a complex mixture of multiple frequencies. When this complex mixture is embedded on a carrier, two sidebands are created that are mirror images.
Modulation Amplitude Modulation 50% 25% 25%
Modulation Single Sideband (SSB) AM is made up of identical mirror image sidebands plus a carrier We can improve the efficiency of transmission by transmitting only one sideband and then reconstruct the missing sideband & carrier at the receiver.
Modulation Frequency Modulation If we vary the frequency of the carrier in step with the information waveform, FM is produced. FM signals are much more resistant to the effects of noise but require more bandwidth. FM bandwidth (for voice) is between 10 and 15 kHz.
Modulation Phase Modulation If we vary the phase of the carrier in step with the information waveform, PM is produced. PM signals are a lot like FM signals. In FM, the amount of deviation is dependent only on the amplitude of the modulating signal. In PM, the amount of deviation is dependent on both the amplitude and the frequency of the modulating signal.
To allow for calibration error in the transmitter frequency display T1B09 -- Why should you not set your transmit frequency to be exactly at the edge of an amateur band or sub-band? To allow for calibration error in the transmitter frequency display So that modulation sidebands do not extend beyond the band edge To allow for transmitter frequency drift All of these choices are correct
Both the frequency and amplitude of the modulating signal T2B05 -- What determines the amount of deviation of an FM (as opposed to PM) signal? Both the frequency and amplitude of the modulating signal The frequency of the modulating signal The amplitude of the modulating signal The relative phase of the modulating signal and the carrier
Its signal occupies more bandwidth Its output power increases T2B06 -- What happens when the deviation of an FM transmitter is increased? Its signal occupies more bandwidth Its output power increases Its output power and bandwidth increases Asymmetric modulation occurs
Microphone gain too high, causing over-deviation SWR too high T2B07 -- What could cause your FM signal to interfere with stations on nearby frequencies? Microphone gain too high, causing over-deviation SWR too high Incorrect CTCSS Tone All of these choices are correct
T8A01 -- Which of the following is a form of amplitude modulation? Spread-spectrum Packet radio Single sideband Phase shift keying
Modulation Comparing Types of Modulation Type of Signal Typical Bandwidth AM Voice 6 kHz AM Broadcast 10 kHz Analog TV 6 MHz SSB Voice 2 kHz to 3 kHz SSB Digital <100 Hz to 3 kHz CW 150 Hz FM Voice 10 kHz to 15 kHz FM Broadcast 180 kHz
FM SSB C. AM D. Spread Spectrum T8A02 -- What type of modulation is most commonly used for VHF packet radio transmissions? FM SSB C. AM D. Spread Spectrum
T8A03 -- 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
T8A04 -- Which type of modulation is most commonly used for VHF and UHF voice repeaters? A. AM B. SSB C. PSK D. FM
A. FM voice B. SSB voice C. CW D. Slow-scan TV T8A05 -- Which of the following types of emission has the narrowest bandwidth? A. FM voice B. SSB voice C. CW D. Slow-scan TV
T8A06 -- 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
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
T8A08 -- What is the approximate bandwidth of a single sideband voice signal? A. 1 kHz B. 3 kHz C. 6 kHz D. 15 kHz
T8A09 -- 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. More than 10 MHz B. About 6 MHz C. About 3 MHz D. About 1 MHz 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
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
Radio Equipment Basics Basic Station Organization All radio stations used for 2-way communications have the same 3 basic parts: Transmitter Receiver Antenna Often the transmitter & receiver are combined into a single unit called a “transceiver”. A hand-held transceiver even includes the antenna.
Radio Equipment Basics Basic Station Organization
Radio Equipment Basics Repeaters A repeater station transmits a received signal simultaneously on another frequency or channel. Most commonly used for FM voice communications. Repeaters allow limited-range stations such as mobile or hand-held transceivers to communicate over longer distances.
Radio Equipment Basics Accessory Station Equipment In addition to the items basic to all 2-way radio stations, you will probably want to add one or more accessory items: Microphone Telegraph key Amplifier Digital interface etc.
Message forwarding station T1F09 -- What type of amateur station simultaneously retransmits the signal of another amateur station on a different channel or channels? Beacon station Earth station Repeater station Message forwarding station
T7A02 -- What is a transceiver? A type of antenna switch A unit combining the functions of a transmitter and a receiver A component in a repeater which filters out unwanted interference A type of antenna matching network
Questions?
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