FCC Technician Class to be used with Element 2 Question Pool 2010-2014 Presented by Jeff Smith W4ZH Course Philosophy (Atleast do the following #2,3,4 & 5) 1. Introduce the concepts of electricity and radio communications 2. Do your own memory work 3. 6 - 12 hours of study will be required 4.. Use of On-Line practice exam: 5. http://www.qrz.com/p/testing.pl 6. What is not covered: Material that is not on the exam 2 Materials Highly recommended Ham Radio License Manual & FCC Rules & Regulations Both are available from the American Radio Relay League [ARRL.org] 3 Materials Available from http://www.w5yi.org/ 1-800-669-9594, or Ham Radio Outlet 1-800-4447927 WWW.ARRL.ORG WWW.QRZ.com 4 Elmers An “Elmer” is an experienced amateur radio operator who helps you get started in amateur radio, study for your license exams or upgrades, or offers any similar encouragement. That’s US! Scott, AL & Jeff If you don’t have an “Elmer” to mentor you, ask for one. 5 HAM Radio???? HAM Radio is a slang term meaning Amateur Radio Jeff Smith’s Great Grandfather “coined” the Term HAM Radio to describe “Hobbyist AMateur Radio” in 1922 Jeff’s Grandfather is Herbert Hoover W3ZH (Just kidding!) 6 The 10 Sub-Elements (6) Rules (4) Electrical Components (3) Operating Procedures (4) Station Equipment (3) Propagation (4) Modulation Modes (2) Amateur Radio Practice (2) Antennas & Feed lines (4) Electrical Principles (3) RF Safety There are 396 questions in the pool. There are 35 questions on the test. We will use 57 real test questions during today's course. 7 Introduction to Amateur Radio The Entry-Level Technician License (Element 2 Exam) Only 3 Classes of “Amateur Radio Licenses” In order of privileges Technician General Extra 9 Entry Level License Technician Written Exam (Element 2) There is no Morse Code requirement Provides all operating privileges above 50 MHz, including the popular 2-meter band; all modes including exotic data and satellite modes 10 What’s this about Morse Code? NONE! Feb 23, 2007 FCC has eliminated Morse Code! Right: Scott Teerlinck MLI and J.Smith PNS teaching one of the TSA MARS Hands On Radio Class in MLI (Very Cold) 11 Why Amateur Radio? 73’s (means “Best Wishes”) How the FCC Defines the Amateur Radio Service Sec. 97.1 Basis and purpose FCC RULES Part 97 More on FCC Part 97 Rules at www.fcc.gov The rules and regulations in this part are designed to provide an amateur radio service having a fundamental purpose as expressed in the following principles: (a) Recognition and enhancement of the value of the amateur service to the public as a voluntary non-commercial communication service, particularly with respect to providing emergency communications. (b) Continuation and extension of the amateur’s proven ability to contribute to the advancement of the radio art. 13 (c) Encouragement and improvement of the amateur service through rules which provide for advancing skills in both the communication and technical phases of the art. (d) Expansion of the existing reservoir within the amateur radio service of trained operators, technicians and electronics experts. (e) Continuation and extension of the amateur’s unique ability to enhance international goodwill. 14 For whom is the Amateur Radio Service untended? A. Persons who have messages to broadcast to the public B. Persons who need communications for the activities of their immediate family members, relatives and friends C. Persons who need two-way communications for personal reasons D. Persons who are interested in radio technique solely with a personal aim and witout pecuniary interest 15 Rules Can’t we all just get along? Courtesy and Common Sense With only a few exceptions that may seem silly, the rules are basically common sense No music (except from NASA) No payment, unless you are teaching in a school No profanity or obscenity, no exceptions! In a life or property threatening emergency, just about anything goes. 17 Control Operator Control Operator: An amateur operator designated by the licensee of a station to be responsible for the transmissions from that station to assure compliance with the FCC rules. Generally, that means YOU You can allow another licensed amateur to use your station equipment and call sign 18 Third Party Communications Third Party Communications: A message from the control operator (1st party) of an amateur station to another amateur station control operator (2nd party) on behalf of another person (3rd party) Be sure there is a 3rd party agreement between the US and the other station’s country before handling 3rd party traffic. 19 Maximum Transmitter Power In HF Technician Bands, 200 watts Peak Envelope Power (PEP) In most other bands, 1500 watts PEP except for some restrictions on Technician class. In all cases, use the minimum power required to make a reliable contact. 20 Station Identification FCC rules require amateur stations to identify every 10 minutes and at the end of transmissions Do not make unidentified transmissions, (with some exceptions, like for Radio Controlled toys.) Note: More about station identification will be covered under “Operating Procedures” 21 About Your Call sign Amateur call signs in the US begin with the letters A, K, N or W Each call sign contains a one-digit number, zero through nine (0 – 9) The arrangement of letters indicates license class, with shorter calls going to higher license classes (W3ABC is legit!) Licenses are good for 10 years There is a 2 year grace period for renewal 22 ITU “International Telecommunications Union” Region 2 is North America!!!” 23 Technician class - Band Privileges All amateur bands 50 MHz and above All available modes No power restrictions NO PRIVILEGES ON FREQUENCIES BELOW 50 MHz! 24 ARRL CALL DISTRICT MAP 25 Technician with Morse Code NEWINGTON, CT, Feb 23, 2007 -- A new Amateur Radio Service regime now is in place. The requirement to demonstrate Morse code proficiency to gain HF privileges officially disappeared from the FCC's Part 97 rules today at 12:01 AM Eastern Time. At the same time, some 200,000 Technician licensees without Morse code exam credit acquired HF privileges equivalent to those available to Novice licensees. 26 Former Novice-class Band Privileges Band 80 m 40 m 15 m 10 m 1.25 m 23 cm Freq. In MHz 3.675 - 3.725 7.100 - 7.150 21.100 - 21.200 28.100 - 28.300 28.300 - 28.500 222.0 - 225.0 1270 - 1295 Mode cw cw cw cw ssb all modes all modes Power 200 W 200 W 200 W 200 W 200 W 25 W 5W 27 Amateur Radio Frequency Bands 28 The Relationship of Frequency and Wavelength The distance a radio wave travels in one cycle is called wavelength. V+ One Cycle 0V time VOne Wavelength 29 Wavelength Formula To convert from frequency to wavelength also this tells you what Band you are on: 300 Wavelength/Band = freq (MHz) Wavelength and Frequency are Inversely Proportional. As one goes up, the other must go down. 30 On what amateur bands will you find these frequencies? 3.975 21.25 145.21 7,233 28.350 MHz MHz MHz kHz MHz 80/75 meter band _______ 15 meter band _______ 2 meter band _______ 40 meter band _______ 10 meter band _______ 31 What is an amateur station control point? A. The location of the station’s transmitting antenna B. The location of the station transmitting apparatus C. The location in which the control operation function is performed D. The mailing address of the station licensee 32 How soon may you operate a transmitter on an Amateur radio service frequency after you pass the examination required for you first amateur radio license? A. Immediately B. 30 days after the test date C. As soon as your name and call sign appear in the FCC’s ULS database D. You must wait until you receive your license in the mail from the FCC 33 Which of the following types of transmissions Are prohibited? A. Transmissions that contain obscene or indecent words or language B. Transmissions to establish one-way communications C. Transmission to establish model aircraft control D. Transmissions for third party communications 34 What are the frequency limits of the VHF spectrum? A. 30 - 300 kHz B. 30 - 300 MHz C. 300 - 3000 kHz D. 300 - 3000 MHz 35 Which of the following is an acceptable language for use for station identification when operating in a phone sub-band? A. Any language recognized by the United Nations B. Any language recognized by the ITU C. The English language D. English, French or Spanish 36 What amount of 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. No more than 1 watt 37 What is the maximum power allowed when transmitting telecommand signals to radio controlled models? A. 500 milliwatts B. 1 watt C. 25 watts D. 15-- watts 38 Operating Procedures Work the neighborhood on the repeater. Work the world on HF Right is a ProtoType “TSA Go Kit by J. Smith PNS for HF/VHF/UHF Voice and HF Email & will deliver 100 watts Repeaters Repeater: An amateur station that simultaneously retransmits the transmission of another amateur station on a different channel or channels Why? A powerful repeater transmitter located at altitude greatly increases the effective range of weaker hand held and mobile radios. 40 Repeaters In order to use a repeater, you must first know the repeater’s transmit frequency and offset. The offset is the difference in the repeater’s transmit and receive frequencies. Most modern radios will calculate the offset for you. 41 A Repeater in Action Output Freq 145.21 MHz Input Freq 144.61 MHz Offset - 600 kHz 60 miles 42 Repeaters Squelch: A squelch circuit keeps the radio speaker turned off until sufficient RF energy is present at the receiver. This keeps the radio quiet until a signal is received. In a repeater, the squelch also turns on the transmitter. In some areas, there is such a level of RF noise the squelch circuit is constantly opening the audio. What do we do? 43 Repeaters PL Tones: Developed by Motorola, Privacy Lock (PL) tones, or Continuous Tone Coded Squelch System (CTCSS) tones are sub-audible tones sent by your radio to the repeater along with your regular transmission. On a PL equipped repeater, there must be enough signal strength to open the squelch, the PL tone must be present and on the correct frequency, before the repeater will retransmit a signal. 44 Repeaters At the end of each transmission through a repeater, you will hear a “roger beep” or “courtesy tone” (a short beep, or series of beeps). Do not begin your transmission until after you hear the courtesy beep. Do not confuse the roger beep with the PL tone. 45 Repeater Operations Listen! If nobody is there, then the repeater is not in use. Give your call sign once. If the repeater is busy, wait for a break and give your call sign ONCE. DO NOT “KER-CHUNK” THE REPEATER Observe rotation, if there is one. When calling another station, always give the other station’s call sign first, then yours. ID every 10 minutes and at the end of the conversation (QSO), you need not ID after every exchange. 46 Autopatch Amateurs can use the repeater’s “autopatch” to connect to the public telephone network via radio. 47 Autopatch You can make phone calls from your radio All repeaters are required to have a 3 minute transmit time-out feature. This applies to the autopatch as well. Do not abuse the autopatch. Use judgment calling 911. Use of autopatch may be subject to payment of dues to the repeater owner or club. 48 The World of High Frequency (HF) These are the traditional world wide bands people usually associate with ham radio. 49 HF/Single Sideband (SSB) Operations When trying to find a clear frequency, LISTEN FIRST, then ask, “Is this frequency in use? <call sign>.” If the frequency is clear, then call “CQ” 3 x 3 - Call CQ three times followed by your call sign phonetically three times, listen, repeat. When calling another station, always give the other station’s call sign first, then yours. ID every 10 minutes and at the end of the QSO, you need not ID after every exchange. Give stations you contact honest signal reports. 50 The RST Reporting System The RST system is a quick way amateurs use to describe a received signal. Readability 1 = Poor 5 = Good Signal Strength 1 = Poor 9 = Good Tone (CW only) 1 = Poor 9 = Good Note: Do not use the RST system on repeaters. 51 Q-signals Q-signals are a kind of “short-hand” hams use to communicate quickly, especially via Morse Code. Most Q-signals can be used as a question or a statement: “Can you QSY to 7.250?” (change/move) “I will QSY to 7.250” (change/move) 52 Q-signals QRM (man made interference) “Do you hear any QRM?” “There is QRM on the Freq” 53 Q-Signals The use of Q-signals began in the days of the telegraph, where operators developed a way to exchange commonly transmitted information (location, output power, etc.) more efficiently. Some common Q-signals are on the next slide… 54 Q-Signals QRM - Is my transmission being interfered with?/Something is causing interference QRN - Are you troubled by static/noise?/I am troubled by static/noise. QRO - Shall I increase transmitter power?/I am running high power. QRP - Shall I decrease transmitter power?/I am running low power. QRQ - Shall I send faster?/Please send faster. QRS - Shall I send slower?/Please send slower QRT - Shall I stop sending?/I am going off the air. QRZ - Who is calling me? QSB - Are my signals fading?/Your signal is fading. QSL - Can you acknowledge receipt?/I received the message. QSO - Can you communicate with ____ direct?/I will communicate with ________ directly. QSY - Shall I change frequency?/I am changing frequency to _______. QTH - What is your location?/My location is _______. 55 QSL Cards A QSL card is a written confirmation of contact between two amateur radio stations. 56 ITU Phonetic Alphabet A Alpha H Hotel O Oscar V Victor B Bravo I India P Papa W Whiskey C Charlie J Juliet Q Quebec X X-ray D Delta K Kilo R Romeo Y Yankee E Echo L Lima S Sierra Z Zulu F Foxtrot M Mike T Tango G Golf N November U Uniform 57 ITU Phonetic Alphabet Used for accurate copy when band conditions are noisy or crowded. Always use the proper words, they were carefully selected so no two sound alike. Avoid being cute. Generally not needed on repeaters. 58 Some No-No’s Don’t use CB slang or 10-codes!!!! Don’t interrupt conversations (QSO’s) in progress. Don’t tune up on the air, use a dummy load. Avoid subject matter that could be offensive. Don’t forget your manners – be polite. Don’t whine and complain. Don’t forget that the whole world can hear you! 59 What is the term used to describe an amateur station that is transmitting and receiving on the same frequency? A. Full duplex communication B. Diplex communication C. Simplex communication D. Half duplex communication 60 What is the FCC Part 97 definition of a space station? A. Any multi-stage satellite B. An Earth satellite that carries one or more amateur operators C. An amateur station located less than 25 km above the Earth’s surface D. An amateur station located more than 50 km above the Earth’s surface 61 Which of the following meets the FCC definition of harmful interference? A. Radio transmissions that annoy users of a repeater B. Unwanted radio transmissions that cause costly harm to radio station apparatus C. That which seriously degrades, obstructs or repeatly interrupts a radio communication service operating in accorddance with Radio Regulations D. Static from lightning storms 62 What is the term for an FCC-issued primary station/operator license grant? A. Five years B. Life C. Ten years D. Twenty years 63 What is the most common repeater freguency offset in the 2 meter band? A. plus 500 khz B. Plus or minus 600 khz C. Minus 500 khz D. Only plus 600 khz 64 What is an appropriate way to call another station on a repeater if you know the other station’s call sign? A. Say “break, break” then say the station’s call sign B. Say the station’s call sign then identify your call sign C. Say “CQ” three times then the other station’s call sign D. Wait for the station to call “CQ” then answer it 65 INTERMISSION 66 Propagation How radio waves get there… and back. Right is Jeff Cram KI4VZQ testing the TSA Network Satellite HF Propagation It is the unpredictable nature of HF propagation that makes the HF bands so much fun. Long distance communication (DX) is accomplished by the reflection of radio waves by the ionosphere, the upper layers of the atmosphere ionized by ultraviolet radiation from the sun. 68 Ionospheric Protection The ionosphere and magnetosphere protect us from harmful radiation from the sun. 69 How the Ionosphere is Formed 70 The Ionosphere F2 Layer (Reflecting) F1 Layer (Reflecting) E Layer (Reflecting) D Layer (Absorbing) 71 Layers of the Ionosphere D Layer, Absorbing, Disappears at night E Layer, Reflecting, Disappears at night F1 and F2 Layers, Reflecting, combine into a single F layer at night. The reflective layers are responsible for sky wave propagation. 72 Line of Sight Propagation Worldwide communications by line of sight is not possible due to the curvature of the Earth 73 Sky wave Propagation Over the horizon communication is possible by skywave propagation, bouncing signals off the ionosphere. 74 Sunspots Sunspots peak during 11-year cycles. The higher the sunspot count, the more the atmosphere is ionized. Thus, higher sunspot counts support a higher Maximum Usable Frequency (MUF). 75 VHF/UHF Propagation Generally line of sight Can be blocked by and/or reflected off mountains and large buildings – even the Moon! Temperature inversions in the troposphere can cause “ducting,” and a path will open briefly for 500 - 600 miles. VHF/UHF will penetrate the Ionosphere, making these frequencies ideal for satellite, and Earth-Moon-Earth (EME) operations. 76 VHF/UHF Propagation VHF/UHF signals travel only in straight lines. We call this “line of sight” propagation Direct communications are not possible because of the mountain 77 What is the cause or irregular fading of signals from distant stations during times of generally good reception? A. Absorption of signals by the “D” layer of the ionosphere B. Absorption of signals by the “E” layer of the ionosphere C. Random combining of signals arriving via different path lengths D. Intermodulation distortion in local receiver 78 What part of the atmosphere enables the propagation of radio signals around the world? A. The stratosphere B. The troposphere C. The ionosphere D. The magnetosphere 79 How does the wavelength of a radio wave relate to its frequency? A. The wavelength gets longer as its frequency increases B. The wavelength gets shorter as the frequency increases C. There is no relationship between wavelength and frequency D. The wavelength depends on the bandwidth of the signal 80 What property of radio waves is often used to identify the different frequency bands? A. The approximate wavelength B. The magnet intensity of waves C. The times it takes the waves to travel one mile D. The voltage standing wave ratio of waves 81 What is the formula for converting frequency to wavelength in meters? A. Wavelength in meters equals frequency in hertz multiplied by 300 B. Wavelength in meters equals frequency in hertz divided by 300 C. Wavelength in meters equals frequency in megahertz divided by 300 D. Wavelength in meters equals 300 divided by frequency in megahertz 82 Amateur Radio Practice Doing things right. Right: KC9OKC Scott Teerlinck, Moline, IL Safety Amateur Radio is a relatively safe hobby. There are only a few ways to get hurt or killed being a ham radio operator: 1. Electrocute yourself. 2. Fall off a tower, or the inverse, have someone/something fall on you from a tower. 3. Slowly cook yourself with RF energy. 84 It Just Kills Me... People have been killed by as little as 30 Volts. As little as 1/10 (100 milliamps) of an amp can be fatal. AC is more dangerous than DC, as it interferes with heart rhythm. The path electric current takes across the body is important. Therefore, always keep one hand in your pocket when working near dangerous voltages. 85 Ground Everything 86 High Voltage Safety Ground all the equipment cases. Make sure your power outlets are grounded. Do not defeat safety interlocks on equipment that contain lethal voltages. Remember, capacitors can store a charge for a really long time. Care should be taken to discharge them. 87 Antenna Safety Don’t put antennas. where they could fall across power lines Don’t climb towers without a safety belt. Don’t do tower work without a ground crew. If you’re working under the tower, wear a hard hat. 88 Lightning Ground antennas when not in use. Ground the tower structure itself. Ground rods should be copper or copper clad steel and 8 ft. long. Disconnect AC power mains during storms, or use line conditioners or surge suppressors. GET OFF THE AIR DURING SEVERE STORMS!! 89 117 Volt AC Outlet Ground Hot Neutral For safety and fire protection, each outlet in your home should be wired exactly this way. Match the colored wires to the colored screws on the outlet. 90 Multimeter (Analog) These meters will measure Voltage, Resistance and Current. The handiest piece of test equipment any ham could own. 91 Digital Multimeter These modern multimeters are easier to use and harder to break than older analog meters. The higher input impedance makes them more accurate. Many include extra features like diode and transistor test functions. 92 S - Meter The S - meter gives a relative signal strength reading of a received signal. No manufacturer claims their S - meters are calibrated. 93 SWR Meter Measures transmitter output power and reflected power from the antenna system 94 Reflectometer The reflectometer is a fancy SWR meter showing forward power, reflected power and SWR all at once. They require no set up or calibration to use. 95 Dummy Load Use a dummy load to tune your transmitter. This is good practice as it reduces QRM and gives the transmitter a perfect 50 ohm load. Note: Dummy loads get hot. 96 Low-Pass Filter A low-pass filter goes between your transmitter and antenna. It removes harmonic radiation from your signals. Your neighbors’ TV sets will thank you. 97 What is considered to be a proper grounding method for a tower? A. A single four-foot ground rod, driven into the ground no more than 12 inches from the base B. A ferrite-core RF choke connected between the tower and ground C. Separate eight-foot long ground rods for each tower leg, bonded to the tower and each other D. A connection between the tower base and a cold water pipe 98 What reading on an SWR meter indicates a perfect impedance match between the antenna and the feedline? A. 2 to 1 B. 1 to 3 C. 1 to 1 D. 10 to 1 99 Where must a filter be installed to reduce harmonic emissions? A. Between the transmitter and the antenna B. Between the receiver and the transmitter C. At the station power supply D. At the microphone 100 What is connected to the green wire in a threewire electrical AC plug? A. Neutral B. Hot C. Safety ground D. The white wire 101 Which of the following might damage a multimeter? A. Measuring a voltage too small for the chosen scale B. Leaving the meter in the milliamps position overnight C. Attempting to measure voltage when using the resistance setting D. Not allowing it to warm up properly 102 Electrical Principles A battery, a bulb and some wire… and a little math. Right is W4ZH Jeff Smith “Go Kit” Prototype in a Car/Truck Units of Measurement Hertz Volts Amps Ohms Farads Henries Watts Frequency (cycles per second) Electromotive Force Electrical Current Resistance (to current flow) Capacitance Inductors Power (the ‘work’ being done) 104 Ohms Law Ohms Law is applicable to all electrical circuits. Ohms Law is a mathematical expression of the relationship between Voltage (EMF), Current (the flow of electrons in a circuit), and Resistance (to current flow). Expressed as E = I x R 105 Voltage and Current? + I E - R A It is possible to have voltage without current, as in the case of a battery by itself. In order to have current, there must be an electrical path (circuit) from the positive to the negative terminal of the voltage source. 106 Ohms Law Electromotive Force = VOLTS E The flow of electrons AMPERES I R Resistance to current flow OHMS 107 Ohms Law + E/R = I 12 volts - 4 ohms 3 ohms 2 ohms A As we substitute the values shown, what happens to the current flow in the circuit? 12/4 = 3 12/3 = 4 12/2 = 6 108 Power Energy Expended, in WATTS P The flow of electrons AMPERES I E Electromotive Force VOLTS 109 Volts, Amps and Watts + 12 volts 4 ohms - A 3 The current in this circuit = _________ Amps 36 The power in this circuit = _________ Watts 110 System of Metric Units giga G 109 1,000,000,000 mega M 106 1,000,000 kilo K 103 1,000 100 1 basic unit milli m 10-3 0.001 micro u 10-6 0.0000001 pico p 10-12 0.000000000001 111 Which is a commonly accepted value for the lowest voltage that can cause a dangerous electric shock? A. 12 volts B. 30 volts C. 120 volts D. 300 volts 112 If an ammeter calibrated in amperes is used to measure a 3000-milliampere current, what reading would it show? A. 0.003 amperes B. 0.3 amperes C. 3 amperes D. 3,000,000 amperes 113 Which of the following is a good electrical conductor? A. B. C. D. Glass Wood Copper Rubber 114 Which instrument would you use to measure electric potential or electromotive force? A. An ammeter B. A voltmeter C. A wavemeter D. An ohmmeter 115 Electrical power is measured in which of the following units? A. B. C. D. Volts Watts Ohms Amperes 116 Circuit Components The stuff radios are made of. Right: Scorpion Antenna goes with the “Go Kit” Resistors + 12 volts 3 Amps - 4 ohms A As we have seen, resistors limit the flow of current. 118 Adding Resistors In Series circuits: Rt = R1 + R2 + R3… In Parallel circuits: Rt = R1 x R2 R1+R2 119 Resistors 120 Resistors 121 Resistor Summary Resistors oppose (resist) the flow of current. Resistors add in series, “Product over the Sum” in parallel. Resistors vary in size and material according to heat dissipation. The Unit of Measure is the Ohm. 122 DC and AC Direct Current Alternating Current 123 A Word about Magnets Remember: 1. Like charges repel and opposite charges attract 2. We can induce a current in a conductor passing through a magnetic field. 124 Inductors 125 Inductors Anytime current flows through a conductor, a magnetic field is created around that conductor. 126 Inductors If we form the conductor into a coil shape, we can greatly intensify the strength of the magnetic field. We can store electrical energy in this magnetic field. 127 Inductors When we close the switch, current flows through the inductor, building a magnetic field. When we open the switch, the field collapses, inducing a current in the inductor. 128 Inductors The value of an inductor can be varied by: Coil Spacing Coil Diameter Number of Turns Core Material The Unit of Measure is the Henry. 129 Adding Inductors In Series circuits: Lt = L1 + L2 + L3… In Parallel circuits: Lt = L1 x L2 L1 + L2 130 Inductor Summary Inductors store electrical energy in their magnetic fields. Inductors are additive in series, “product over the sum” in parallel. Inductors tend to pass DC currents and block AC currents. The unit of measurement for inductors is the Henry. 131 Capacitors 132 Capacitors A capacitor is made by separating two conductive plates by an insulator or dielectric. Capacitors store electrical energy in an electrostatic field. Capacitors tend to block DC and pass AC 133 Capacitors Remember: Like charges repel. Current will flow only until one plate is full of negatively charged electrons the other has almost none. This creates a difference of potential (a voltage) across the plates almost like a battery. 134 WARNING! CAPACITORS CAN HOLD A CHARGE FOR QUITE SOME TIME. They would be very happy to bite you. 135 Intermission 136 Capacitors The Value of a capacitor can be varied by: Increasing/decreasing the plate area Increasing/decreasing the plate spacing Type of dielectric material The Unit of Measure is the Farad. 137 Adding Capacitors Capacitors add in parallel Ct = C1 + C2 + C3… In Series Ct = C1 x C2 C1 + C2 Note: this is backwards from resistors and inductors. 138 Capacitor Summary Capacitors store electrical energy in their electrostatic fields. Capacitors are additive in parallel, “product over the sum” in series. Capacitors tend to pass AC currents and block DC currents. The unit of measurement for Capacitors is the Farad. 139 The Fuse Fuse 140 The Fuse A fuse will self destruct when current flow exceeds the fuse rating. This results in an open condition, and current flow will then cease, saving equipment from overheating and possible fire damage. 141 What electrical component is used to protect other circuit components from current overloads? A. Fuse B. Capacitor C. Shield D. Inductor 142 What does an antenna tuner do? A. It matches the antenna system impedance to the transceiver's output impedance B. It helps a receiver automatically tune in weak stations C. It allows an antenna to be used on both transmit and receive D. It automatically selects the proper antenna for the frequency band being used 143 What type of component is often used as an adjustable volume control? A. Fixed resistor B. Power resistor C. Potentiometer D. Transformer 144 What is the approximate amount of change, measured in decibels (dB), of a power increase from 5 watts to 10 watts? A. 2 dB B. 3 dB C. 5 dB D. 10 dB 145 What electrical component stores energy in an electric field? A. Resistor B. Capacitor C. Inductor D. Diode 146 Practical Circuits Putting it all together. Filters We have learned: Capacitors tend to pass AC and high frequencies Inductors tend to pass DC and low frequencies We can now build circuits that… Block transmission of harmonic radiation Block reception of amateur frequencies Pass only a desired group of frequencies Note the output of each type of filter. 148 What instrument other than an SWR meter could you use to determine if a feedline and antenna are properly matched? A. Voltmeter B. Ohmmeter C. Iambic pentameter D. Directional wattmeter 149 Why is coaxial cable used more often than any other feedline for amateur radio antenna systems? A. It is easy to use and requires few special installation considerations B. It has less loss than any other type of feedline C. It can handle more power than any other type of feedline D. It is less expensive than any other types of feedline 150 1 2 3 If figure T5 represents a transceiver in which block 1 is the transmitter portion and block 3 is the receiver portion, what is the function of block 2? A. A balanced modulator B. A transmit-receive switch C. A power amplifier D. A high-pass filter 151 What type of filter should be connected to a TV receiver as the first step in trying to prevent RF overload from a nearby 2 meter transmitter? A. Low-pass filter B. High-pass filter C. Band-pass filter D. Band-reject filter 152 What is the function of a product detector? A. Detect phase modulated signals B. Demodulate FM signals C. Detect CW and SSB signals D. Combine speech and RF signals 153 Signals and Emissions AM/FM, SSB, CW Alphabet Soup! Right: W4ZH J. Smith in New Orleans testing HF Voice and HF Email FCC Emission Types CW Data Phone Test MCW RTTY Image Pulse SS (Spread Spectrum) 155 CW In CW the telegraph key simply turns the radio transmitter on and off to form the Morse code characters 156 CW and MCW CW (continuous wave) is the on-off keying of a radio signal generally used for Morse code MCW is the tone modulation of a carrier wave made to sound like Morse code, as in the automatic identifiers used on some repeaters. 157 Phone Phone is any voice transmission This includes AM (amplitude modulation) SSB (single side band, similar to AM) FM (frequency modulation) 158 Amplitude Modulation An unmodulated RF carrier wave A carrier wave AM modulated with a simple audio tone 159 AM and SSB An unmodulated RF carrier requires narrow bandwidth Modulation of the carrier creates sidebands. This requires more bandwidth. Transmitter power is spread across this bandwidth 160 AM and SSB The carrier contains no audio information. The sidebands contain duplicate audio information By filtering out the carrier and one sideband, we save spectrum and concentrate our RF energy into a narrower bandwidth. SSB is therefore more efficient. 161 SSB MIXER OSCILLATOR INTERMEDIATE FREQUENCY AMPLIFIER 1 BEAT FREQUENCY OSCILLATOR AUDIO AMPLIFIER Figure T6 What type of receiver is shown in Figure T6? A. Direct conversion B. Super-regenerative C. Single-conversion superheterodyne D. Dual-conversion superheterodyne 162 AM vs. Sounds really nice Inexpensive Simpler equipment SSB More efficient. Further range based on same output power. Narrower bandwidth, more room on crowded bands. All modern HF radios support SSB (not all support AM) 163 AM and SSB When SSB is not modulated (when you are not talking) the transmitter output power drops to almost nothing. When either AM or SSB is overmodulated the signal may cause “splatter,” and interfere with other stations. 164 Frequency Modulation Unmodulated carrier, full power at all times Waveform of modulating signal Modulated carrier with frequency deviation and constant amplitude 165 Frequency Modulation FM transmitters operate at full power at all times, even when you are not talking. When an FM transmitter overmodulates, the transmitted signal becomes so wide (bandwidth) it may interfere with adjacent channels. This is called over-deviation. 166 Image Image transmissions include all modes that will produce a picture, either video or paper copy (like a FAX) at the receiver. These modes include: SSTV (slow scan television) ATV (amateur television) FAX (facsimile) 167 Image A sample amateur SSTV transmission. 168 Image Amateurs like to receive weather images direct from the satellites. The equipment is inexpensive and you don’t even need a license! 169 Data and RTTY RTTY (radio teletype) was the forerunner of all modern digital mode transmission. Today, amateurs use many kinds of intelligent on air networking modes. Collectively, the FCC refers to these intelligent modes as “Data.” Both Data and RTTY require an interface between the Data or RTTY device and the transceiver. 170 Data vs. Error correcting Store and forward networking Addressable Packet oriented Will interface with the Internet Requires TNC to interface with radio RTTY No error correction Direct contact No addressing Continuous data stream No way!! Requires “modem” to interface with radio 171 A Packet Network With only a few watts, you can connect to an on-air network. Your data packets will be forwarded to hams all over the country. Packet type protocols include: Packet and APRS, COVER, PACTOR I, II & III G-TOR (This is what TSA uses for HF Email) 172 A Packet Network 173 A Packet Network A digipeater is a packet-radio station capable of recognizing and selectively repeating packet frames. All the stations on a packet network share the same frequency. By the use of digipeaters, a packet can be reliably sent error free over great distances. 174 TNCs The “Terminal Node Controller” (TNC) interfaces your computer to your transceiver. 175 TNCs (like the old dial up modems we used to get on the Internet) 176 Test, SS and Pulse Test emissions are simply unmodulated carrier. SS (Spread Spectrum) are experimental frequency hopping modes. Pulse emissions are used for telemetry. 177 What method of call sign identification is required for a station transmitting phone signals? A. Send the call sign followed by the indicator RPT B. Send the call sign using CW or phone emission C. Send the call sign followed by the indicator R D. Send the call sign using only phone emission 178 Which of the following would be connected between a transceiver and computer in a packet radio station? A. Transmatch B. Mixer C. Terminal node controller D. Antenna 179 What happens when the deviation of an FM transmitter is increased? A. Its signal occupies more bandwidth B. Its output power increases C. Its output power and bandwidth increases D. Asymmetric modulation occurs 180 Which type of modulation is most commonly used for VHF and UHF voice repeaters? A. AM B. SSB C. PSK D. FM 181 What can you do if you are told your FM handheld or mobile transceiver is over deviating? A. Talk louder into the microphone B. Let the transceiver cool off C. Change to a higher power level D. Talk farther away from the microphone 182 Antennas Antennas and Feed lines Antenna systems are resonant - that is, they respond best to a certain frequency. For best operation, the transmitter, feed line and antenna must all be tuned to resonance or something that looks like resonance. The transmitting antenna induces a radio wave into the air. The radio wave travels to the receiving antenna, and induces a current in that antenna. 184 The 1/2 Wave Dipole Length of dipole in feet = 468 f (MHz) 185 The 1/2 Wave Dipole 186 The 1/4 Wave Vertical Length of vertical in feet = 234 f (MHz) 187 The 1/4 Wave Vertical A side view of the radiation pattern of a 1/4 wave vertical. From above the pattern is round like a doughnut. A perfect ground would be a car roof. 188 The Yagi (Type of Beam Antenna) The yagi is the ham’s favorite directional antenna. They usually consist of one driven element, and several “parasitic” (un-driven) elements. Reflector (longer than driver) Driven Element (1/2 wave dipole) One or more Directors (shorter than the driven element) 189 The director acts like a lens Director Boom Feedline Reflector The reflector acts like a mirror Driver The Yagi Gain 190 The Yagi The yagi antenna focuses RF energy in one direction, giving the appearance ofgetting “free power.” This free power is called Antenna Gain. 191 The Yagi (Beam Antenna) A 3 element HF Yagi A VHF Yagi 192 Feed lines Feed line connects your radio to the antenna. Feed lines are either balanced (neither side grounded) like ladder-line or unbalanced (one side grounded) like coaxial cable. Either type can be used in your station. Coax is more popular and easier to work with. 193 Coax vs. Can be buried or run near metal objects. Less RFI since outer shield is usually grounded. Weatherproof Easy to handle and connect Ladder Line Very low signal loss Can tolerate high SWR Can tolerate high current 194 Coax All coaxial cable will feature a center conductor surrounded by a dielectric insulator and one or more layers of shielding and an insulating cover. 195 The Balun The balun converts from BALanced feed line to UNbalanced feed lines. Many antenna systems work better with a balun between the feed point and the coax 196 SWR SWR (standing wave ratio) is a mathematical expression of the power going to an antenna and the power being reflected back. The idea is to get as close to 1:1 as possible. Most hams are happy with SWR of 1.5:1. The best way to get a good SWR is to cut the antenna to resonance. 197 The Antenna Tuner “Antenna Tuners” do not really tune antennas. They provide an impedance match between the transmitter and antenna system. 198 What is the approximate length, in inches, of a 6 meter 1/2-wavelength wire dipole antenna? A. 6 B. 50 C. 112 D. 236 199 What is the approximate length, in inches, of a quarter-wavelength vertical antenna for 146 MHz? A. 112 B. 50 C. 19 D. 12 200 How would you change a dipole antenna to make it resonant on a higher frequency? A. Lengthen it B. Insert coils in series with radiating wires C. Shorten it D. Add capacity hats to the ends of the radiating wires 201 Which of the following describes a simple dipole mounted so the conductor is parallel to the Earth's surface? A. A ground wave antenna B. A horizontally polarized antenna C. A rhombic antenna D. A vertically polarized antenna 202 What type of antennas are the quad, Yagi, and dish? A. Non-resonant antennas B. Loop antennas C. Directional antennas D. Isotropic antennas 203 What is a disadvantage of the "rubber duck" antenna supplied with most handheld radio transceivers? A. It does not transmit or receive as effectively as a full-sized antenna B. It transmits a circularly polarized signal C. If the rubber end cap is lost it will unravel very quickly D. All of these choices are correct 204 What, in general terms, is standing wave ratio (SWR)? A. A measure of how well a load is matched to a transmission line B. The ratio of high to low impedance in a feedline C. The transmitter efficiency ratio D. An indication of the quality of your station’s ground connection 205 RF Safety Can’t touch this. Intermission 207 2 Types of Radiation Ionizing Gamma and X-ray Can cause ionization of atomic structure Not good for your DNA Non-ionizing Radio waves Can cause heating of biological tissue If sufficient energy is present, can cause burns 208 RF Heating Radio waves can heat body tissue. Works exactly like your microwave oven. The area most likely to be injured is the eye as it lacks sufficient blood flow for cooling. The eye can form cataracts from repeated exposure to high levels of RF energy. NEVER touch an antenna or other RF source. You could be severely burned. 209 Controlled and Uncontrolled Environments Controlled Environments The amateur operators household and property Persons here are aware of RF risks, and have control of the transmitting equipment. Uncontrolled Environments Your neighbors household and property Persons here are generally not aware of RF risks and have NO control over the transmitter. 210 Exposure Averaging Times Controlled Environments The exposure averaging time is 6 Minutes Uncontrolled Environments The exposure averaging time is 30 Minutes 211 3 Methods of RF Checking Measure the RF fields requires costly equipment that you don’t have Calculate the RF fields requires complex software that you don’t have Use the charts published by the FCC The charts are free Fairly simple to use 212 RF Safety for Dummies Install your antenna away from people, especially your neighbors. The higher the better. Make sure your antenna is not near or could fall on a power line. Keep your hands and other body parts away from the antenna and feed lines. 213 Who is Exempt? The RF safety regulations do not apply to: Mobile equipment Hand-held radios Any station that produces less than 50 watts PEP 214 What is the minimum safe distance from a power line to allow when installing an antenna? A. Half the width of your property B. The height of the power line above ground C. 1/2 wavelength at the operating frequency D. So that if the antenna falls unexpectedly, no part of it can come closer than 10 feet to the power wires 215 What is the maximum power level that an amateur radio station may use at VHF frequencies before an RF exposure evaluation is required? A. 1500 watts PEP transmitter output B. 1 watt forward power C. 50 watts PEP at the antenna D. 50 watts PEP reflected power 216 What could happen if a person accidentally touched your antenna while you were transmitting? A. Touching the antenna could cause television interference B. They might receive a painful RF burn C. They might develop radiation poisoning D. All of these choices are correct 217 Why is duty cycle one of the factors used to determine safe RF radiation exposure levels? A. It affects the average exposure of people to radiation B. It affects the peak exposure of people to radiation C. It takes into account the antenna feedline loss D. It takes into account the thermal effects of the final amplifier 218 Which of the following actions might amateur operators take to prevent exposure to RF radiation in excess of FCC-supplied limits? A. Relocate antennas B. Relocate the transmitter C. Increase the duty cycle D. All of these choices are correct 219 What to Expect at the Exam Session There will be a fee ($15) to take as many tests as you like, as long as you are passing them. To retest, just pay another $15 All the elements will be offered. Bring photo identification and your Social Security card. Children will need to show a birth certificate. The tests are not timed. Bring a #2 pencil. 220 What to Expect at the Exam Session You can bring a calculator. Do not write in the test booklet. You can ask for scratch paper to doodle on. You can retest any time, but usually NOT more than once at the same session. The Element 2 - Technician Class Exam consists of 35 multiple choice questions,(you can miss 9) and you must answer 75% or better to pass. 221 Who passes the exams? Those who: Prepare by studying 30 min to one hour a day. Take their time on the exam. Ask for help from an Elmer. Keep trying, Never ever give up!!!!!! 222 Your new Call Sign You can get on the air as soon as you know your new call sign. ie: in the FCC Database!! Visit the Universal Licensing System on www.ftc.gov or do a Name Search on www.qrz.com, 6 - 8 days after you pass your exam. Your license will arrive in the mail in a few weeks. 223 Welcome to the World of Amateur Radio What to do with that new call sign Now that I am a Amateur Radio Operator, What Do I Do? Support Amateur Radio locally. Be involved in local clubs and associations. Get involved in community service through your local ARES group, or the American Red Cross. Join the American Radio Relay League (ARRL) More importantly, get on the air and say something! 225 ARES ARES is the local community emergency services organization where hams can serve as only amateur radio can…providing communications for emergencies and special events. 226 Why join the ARRL? Since 1914 the American Radio Relay League has represented the interests of Radio Amateurs before the FCC and Congress. While there is room for policy debate, those who do not support the ARRL have virtually no voice in matters concerning ham radio. Also, the QST magazine is an excellent educational tool, full of interesting articles and fun projects. 227 Where do I go from here? Stamp Collecting Meteorology Geography Computers Radio Astronomy Emergency Services Support your local Amateur Radio organization! 228 This Completes the Course… …and begins a worldwide journey that will last you a lifetime. Enjoy your new hobby! 73’s de W4ZH Jeff Smith Pensacola, FL 229