South African Radio League Introduction to Amateur Radio South African Radio League Introduction to Amateur Radio A study guide for the Radio Amateur Examination Edition 1.2 January 2016 ISBN 978-0-620-69471-1 V1.2 © 2005 to 2016 SARL 1 South African Radio League Introduction to Amateur Radio Table of Contents Table of Contents ................................................................................................................... 2 Version Control .................................................................................................................... 10 Preface .................................................................................................................................. 11 Chapter 1: Overview of Amateur Radio .............................................................................. 12 1.1 Communicating With Other Amateurs ...................................................................... 12 1.2 Collecting QSL Cards ................................................................................................ 12 1.3 Building Radio and Electronics Equipment ............................................................... 13 1.4 Building Antennas ...................................................................................................... 13 1.5 Public Service and Emergency Communications ...................................................... 13 1.6 DXing ......................................................................................................................... 13 1.7 DXpeditions ............................................................................................................... 14 1.8 Contests ...................................................................................................................... 14 1.9 Satellite Communications .......................................................................................... 14 1.10 Maritime and Off-Road Communications................................................................ 14 1.11 Licence Requirements in South Africa .................................................................... 14 The Class A Licence (ZR or ZS callsign) .................................................................... 15 The Class B Licence (ZU callsign) .............................................................................. 15 1.12 The Radio Amateurs’ Examination .......................................................................... 15 1.13 Restrictions on the Use of an Amateur Radio Station .............................................. 16 Chapter 2: Operating Procedures ......................................................................................... 17 2.1 International Regulations ........................................................................................... 17 The ITU ........................................................................................................................ 17 CEPT ............................................................................................................................ 17 The IARU ..................................................................................................................... 18 Callsigns ....................................................................................................................... 18 2.2 HF Phone Procedures ................................................................................................. 19 The Phonetic Alphabet ................................................................................................. 19 Initiating Contacts ........................................................................................................ 20 Responding to a CQ ..................................................................................................... 20 Exchanging Reports ..................................................................................................... 21 Ending the QSO ........................................................................................................... 22 After the Contact .......................................................................................................... 23 What Not to Do ............................................................................................................ 23 2.3 Telegraphy Procedures ............................................................................................... 23 Abbreviations ............................................................................................................... 24 Initiating Contacts ........................................................................................................ 24 Replying to a CQ .......................................................................................................... 25 Quick turnaround ......................................................................................................... 26 Ending the QSO ........................................................................................................... 26 2.4 Repeater Procedures ................................................................................................... 27 2.5 Emergency Communications and Social Responsibility ........................................... 29 2.6 General Points ............................................................................................................ 29 2.7 Keeping a Log ............................................................................................................ 30 2.8 Exchanging QSL Cards .............................................................................................. 31 Revision Questions .......................................................................................................... 33 Chapter 3: Basic Electrical Concepts ................................................................................... 43 3.1 Atoms and Electrons .................................................................................................. 43 3.2 Conductors and Insulators .......................................................................................... 43 3.3 Electric Current .......................................................................................................... 44 3.4 Electric Potential ........................................................................................................ 44 3.5 Units and Abbreviations ............................................................................................. 45 3.6 Scientific Notation ..................................................................................................... 45 V1.2 © 2005 to 2016 SARL 2 South African Radio League Introduction to Amateur Radio 3.7 Number Formats ........................................................................................................ 46 Summary .......................................................................................................................... 46 Revision Questions .......................................................................................................... 46 Chapter 4: Resistance and Ohm’s Law ................................................................................ 48 4.1 Resistance................................................................................................................... 48 4.2 Symbols in Mathematical Equations .......................................................................... 48 4.3 Rearranging Ohm’s Law ............................................................................................ 49 Summary .......................................................................................................................... 50 Revision Questions .......................................................................................................... 50 Chapter 5: The Resistor and Potentiometer ......................................................................... 52 5.1 The Resistor ............................................................................................................... 52 5.2 Different Types of Resistor ........................................................................................ 52 5.3 The Resistor Colour Code .......................................................................................... 53 5.4 Expressing Resistor Values ........................................................................................ 54 5.5 The Potentiometer ...................................................................................................... 54 Summary .......................................................................................................................... 55 Revision Questions .......................................................................................................... 55 Chapter 6: Direct Current Circuits ....................................................................................... 57 6.1 Direct Current and Voltage ........................................................................................ 57 6.2 Kirchoff’s Laws ......................................................................................................... 57 6.2 Resistors in Series ...................................................................................................... 59 6.3 Resistors in Parallel .................................................................................................... 61 Practical Example......................................................................................................... 62 6.4 The Voltage Divider ................................................................................................... 63 Summary .......................................................................................................................... 64 Revision Questions .......................................................................................................... 64 Chapter 7: Power in DC Circuits ......................................................................................... 66 7.1 Power Dissipation in Resistances............................................................................... 66 7.2 Using Ohm’s Law with the Formula for Power ......................................................... 66 Exercise ........................................................................................................................ 67 7.3 Electrical Sources ....................................................................................................... 67 7.4 Matching Source and Load ........................................................................................ 68 Summary .......................................................................................................................... 69 Revision Questions .......................................................................................................... 69 Chapter 8: Alternating Current............................................................................................. 72 8.1 Introduction ................................................................................................................ 72 8.2 The Sine Signal .......................................................................................................... 72 8.3 Cycles and Half Cycles .............................................................................................. 74 8.4 Period and Frequency ................................................................................................. 74 8.5 Wavelength and the Speed of Light ........................................................................... 74 8.6 Phase .......................................................................................................................... 76 8.7 RMS Voltage and Current .......................................................................................... 76 8.8 Frequency Ranges ...................................................................................................... 78 Summary .......................................................................................................................... 78 Revision Questions .......................................................................................................... 79 Chapter 9: Capacitance and the Capacitor ........................................................................... 81 9.1 The Capacitor ............................................................................................................. 81 9.2 Capacitors in AC Circuits .......................................................................................... 82 9.3 Capacitive Reactance ................................................................................................. 83 9.4 Phase of Current and Voltage .................................................................................... 84 9.5 Capacitors in Parallel and Series ................................................................................ 85 9.6 Types of Capacitor ..................................................................................................... 86 Summary .......................................................................................................................... 86 Revision Questions .......................................................................................................... 87 V1.2 © 2005 to 2016 SARL 3 South African Radio League Introduction to Amateur Radio Chapter 10: Inductance and the Inductor ............................................................................. 89 10.1 Inductors................................................................................................................... 89 10.2 Inductor Values ........................................................................................................ 90 10.3 Inductors in AC Circuits .......................................................................................... 90 10.4 Inductive Reactance ................................................................................................. 91 10.5 Ohm’s Law and Reactance....................................................................................... 91 10.6 Phase Relationship between Voltage and Current ................................................... 91 10.7 Inductors in Series and Parallel ................................................................................ 92 Summary .......................................................................................................................... 92 Revision Questions .......................................................................................................... 93 Chapter 11: Tuned Circuits .................................................................................................. 94 11.1 Reactances in Series ................................................................................................. 94 11.2 Reactances in Parallel .............................................................................................. 95 11.3 The Series Tuned Circuit ......................................................................................... 95 11.4 Impedance ................................................................................................................ 97 11.5 The Parallel Tuned Circuit ....................................................................................... 98 11.6 Circulating Current in a Parallel Tuned Circuit ....................................................... 99 11.7 Calculating the Resonant Frequency ...................................................................... 100 11.8 Circuit Losses and the Quality Factor .................................................................... 100 Summary ........................................................................................................................ 101 Revision Questions ........................................................................................................ 102 Chapter 12: Decibel Notation............................................................................................. 103 12.1 The Decibel ............................................................................................................ 103 12.2 Adding Decibels ..................................................................................................... 103 Example ..................................................................................................................... 103 12.3 Representing Losses ............................................................................................... 103 Example ..................................................................................................................... 104 12.4 Quick and Easy Decibel Conversions .................................................................... 104 12.5 Expressing Voltage Ratios as Decibels .................................................................. 105 12.6 Expressing Power Levels in dBW and dBm .......................................................... 106 Summary ........................................................................................................................ 106 Revision Questions ........................................................................................................ 107 Chapter 13: Filters .............................................................................................................. 108 13.1 The Lowpass Filter ................................................................................................. 108 13.2 The Highpass Filter ................................................................................................ 109 13.3 The Bandpass Filter ............................................................................................... 110 13.4 Crystal Filters ......................................................................................................... 112 13.5 The Bandstop Filter ................................................................................................ 112 13.6 More Sophisticated Filters ..................................................................................... 113 13.7 Practical RF Circuits .............................................................................................. 113 Summary ........................................................................................................................ 114 Revision Questions ........................................................................................................ 114 Chapter 14: The Transformer ............................................................................................. 116 14.1 Theory of Operation ............................................................................................... 116 14.2 Turns Ratio ............................................................................................................. 116 14.3 Voltage Ratio ......................................................................................................... 117 14.4 Current Ratio .......................................................................................................... 118 14.5 Impedance Ratio .................................................................................................... 119 14.6 Applications ........................................................................................................... 120 Summary ........................................................................................................................ 120 Revision Questions ........................................................................................................ 121 Chapter 15: Semiconductors and the Diode ....................................................................... 123 15.1 Semiconductors ...................................................................................................... 123 N-Type Semiconductors............................................................................................. 123 P-Type Semiconductors ............................................................................................. 123 V1.2 © 2005 to 2016 SARL 4 South African Radio League Introduction to Amateur Radio 15.2 The Junction Diode ................................................................................................ 124 15.3 The Half-Wave Rectifier ........................................................................................ 126 15.4 The Full-Wave Rectifier ........................................................................................ 128 15.5 Special Diodes ........................................................................................................ 129 The Zener Diode ........................................................................................................ 129 The Varicap Diode ..................................................................................................... 130 Diodes as Switches ..................................................................................................... 131 The Light-Emitting Diode .......................................................................................... 132 Summary ........................................................................................................................ 132 Revision Questions ........................................................................................................ 133 Chapter 16: The Power Supply .......................................................................................... 135 16.1 Simple Power Supply ............................................................................................. 135 16.2 A Regulated Power Supply .................................................................................... 135 16.3 Switching Power Supplies...................................................................................... 136 16.4 Batteries ................................................................................................................. 138 Recharging ................................................................................................................. 138 Summary ........................................................................................................................ 139 Revision Questions ........................................................................................................ 139 Chapter 17: The Bipolar Junction Transistor ..................................................................... 141 17.1 Types of Transistors ............................................................................................... 141 17.2 Operation of the NPN Transistor ........................................................................... 141 17.3 Operation of the PNP Transistor ............................................................................ 142 17.4 The Transistor Switch ............................................................................................ 143 Summary ........................................................................................................................ 144 Revision Questions ........................................................................................................ 144 Chapter 18: The Transistor Amplifier ................................................................................ 146 18.1 Amplification ......................................................................................................... 146 18.2 Class C Amplifiers ................................................................................................. 146 18.3 The Class A Common-Emitter Amplifier .............................................................. 148 18.4 The Common-Collector (Emitter Follower) Amplifier .......................................... 150 18.5 The Common Base Amplifier ................................................................................ 150 18.6 The Class AB Amplifier......................................................................................... 151 18.7 Field-Effect Transistors .......................................................................................... 152 18.8 Thermionic Tubes .................................................................................................. 152 18.9 Integrated Circuits .................................................................................................. 153 Summary ........................................................................................................................ 154 Revision Questions ........................................................................................................ 155 Chapter 19: The Oscillator ................................................................................................. 157 19.1 Oscillators .............................................................................................................. 157 19.2 Principle of Operation ............................................................................................ 157 19.3 The Barkhausen Criteria for Oscillation ................................................................ 158 19.4 The Colpitts Oscillator ........................................................................................... 160 19.5 Buffering ................................................................................................................ 160 19.6 The Hartley Oscillator ............................................................................................ 161 19.7 The Voltage-Controlled Oscillator ......................................................................... 162 19.8 The Crystal Oscillator ............................................................................................ 162 Summary ........................................................................................................................ 163 Revision Questions ........................................................................................................ 164 Chapter 20: Frequency Translation .................................................................................... 166 20.1 The Frequency Multiplier ...................................................................................... 166 20.2 The Frequency Divider .......................................................................................... 168 20.3 The Phase Locked Loop Frequency Synthesiser .................................................... 168 20.4 The Mixer ............................................................................................................... 170 Summary ........................................................................................................................ 172 Revision Questions ........................................................................................................ 172 V1.2 © 2005 to 2016 SARL 5 South African Radio League Introduction to Amateur Radio Chapter 21: Modulation Methods ...................................................................................... 174 21.1 Modulation ............................................................................................................. 174 21.2 Amplitude Modulation (AM) ................................................................................. 174 21.3 Double-Sideband Suppressed-Carrier Modulation ................................................ 178 21.4 Single-Sideband (SSB) .......................................................................................... 180 21.5 Continuous Wave (CW) ......................................................................................... 181 21.6 Frequency Modulation (FM) .................................................................................. 182 21.7 Digital Modulation Techniques .............................................................................. 184 Frequency-Shift Keying (FSK) .................................................................................. 184 Phase-Shift Keying (PSK).......................................................................................... 184 WSJT .......................................................................................................................... 184 Error Correction ......................................................................................................... 185 Summary ........................................................................................................................ 185 Revision Questions ........................................................................................................ 186 Chapter 22: The Transmitter .............................................................................................. 189 22.1 A Single-Band CW Transmitter ............................................................................. 189 22.2 An Amplitude-Modulated (AM) Transmitter ........................................................ 189 22.3 A Simple SSB Transmitter ..................................................................................... 192 22.4 A Frequency-Synthesised VHF FM Transmitter ................................................... 193 Chapter 23: Receiver Fundamentals .................................................................................. 194 23.1 Noise in Receivers ................................................................................................. 194 23.2 Receiver Characteristics ......................................................................................... 195 Selectivity ................................................................................................................... 195 Sensitivity ................................................................................................................... 195 Dynamic range ........................................................................................................... 195 23.3 The Tuned Radio Frequency (TRF) Receiver ........................................................ 195 23.4 The Direct-Conversion Receiver ............................................................................ 196 Summary ........................................................................................................................ 201 Revision Questions ........................................................................................................ 201 Chapter 24: The Superheterodyne Receiver ...................................................................... 204 24.1 The Single-Conversion Superhet ........................................................................... 204 24.2 Multiple-Conversion Superhet Receivers .............................................................. 206 24.3 Noise Limiters and Noise Blankers ........................................................................ 207 24.4 Frequency Modulation (FM) Reception ................................................................. 208 24.5 Reciprocal Mixing .................................................................................................. 210 Summary ........................................................................................................................ 210 Revision Questions ........................................................................................................ 210 Chapter 25: Transceivers and Transverters ........................................................................ 214 25.1 The Transceiver ...................................................................................................... 214 25.2 The Transverter ...................................................................................................... 215 Summary ........................................................................................................................ 217 Revision Questions ........................................................................................................ 217 Chapter 26: Antennas ......................................................................................................... 218 26.1 Antennas and Electromagnetic Fields .................................................................... 218 26.2 The Half-Wave Dipole ........................................................................................... 219 26.3 The Quarter-Wavelength Vertical .......................................................................... 224 26.4 The Ground Plane Antenna .................................................................................... 225 26.5 Short Antennas ....................................................................................................... 226 26.6 Loop Antennas ....................................................................................................... 227 26.7 Folded Dipole ......................................................................................................... 228 26.8 Multi-element arrays .............................................................................................. 228 26.9 The Yagi ................................................................................................................. 229 26.10 Reflector Antennas ............................................................................................... 231 26.11 Antenna Gain ....................................................................................................... 231 26.12 Effective Isotropic Radiated Power ..................................................................... 232 V1.2 © 2005 to 2016 SARL 6 South African Radio League Introduction to Amateur Radio 26.13 Efficiency ............................................................................................................. 232 26.14 Directivity as Opposed to Gain ............................................................................ 233 26.15 Other Performance Measures ............................................................................... 233 26.16 Stacking ................................................................................................................ 234 26.17 Feedlines .............................................................................................................. 234 Balanced feeders ........................................................................................................ 234 Coaxial cables ............................................................................................................ 235 Waveguides ................................................................................................................ 235 26.18 Standing-Wave Ratio ........................................................................................... 235 26.19 Baluns................................................................................................................... 236 26.20 Multiband Antennas ............................................................................................. 236 Antenna Tuning Unit.................................................................................................. 236 Fan Dipole .................................................................................................................. 237 Traps........................................................................................................................... 238 Multiple Resonances .................................................................................................. 238 26.21 The Log-Periodic Array ....................................................................................... 238 26.22 Making Practical Antennas .................................................................................. 239 Summary ........................................................................................................................ 240 Revision Questions ........................................................................................................ 241 Chapter 27: Propagation ..................................................................................................... 245 27.1 Frequency Bands .................................................................................................... 245 27.2 Direct Wave (Line of Sight) Propagation .............................................................. 245 27.3 Ground Wave Propagation ..................................................................................... 245 27.4 The Atmosphere ..................................................................................................... 246 27.5 Sky Wave (Ionospheric) Propagation .................................................................... 247 27.6 Exotic Ionospheric Propagation Modes ................................................................. 250 Sporadic E Propagation .............................................................................................. 250 Backscatter ................................................................................................................. 250 Meteor Scatter ............................................................................................................ 250 Auroral Scatter ........................................................................................................... 250 27.7 Tropospheric Bending, Scatter and Ducting .......................................................... 250 27.8 Earth Moon Earth (EME) ....................................................................................... 251 27.9 Amateur Satellites .................................................................................................. 251 27.10 Propagation Prediction ......................................................................................... 252 Summary ........................................................................................................................ 253 Revision Questions ........................................................................................................ 254 Chapter 28: Electromagnetic Compatibility ....................................................................... 257 28.1 Definition of Electromagnetic Compatibility ......................................................... 257 28.2 Intentional and Unintentional Radiators ................................................................ 257 28.3 Interference to non-receiving equipment ............................................................... 257 28.4 Intentional Radiators interfering with Receivers ................................................... 258 28.5 Shared Bands .......................................................................................................... 259 28.6 Causes of Interference ............................................................................................ 259 28.7 Transmitter Defects ................................................................................................ 259 28.8 Receiver Defects .................................................................................................... 261 Assessing Interference Sources .................................................................................. 262 28.9 Common-Mode Chokes ......................................................................................... 262 28.10 Direct Radiation and Shielding ............................................................................ 263 28.11 Sensible Measures against Interference ............................................................... 264 Summary ........................................................................................................................ 264 Revision Questions ........................................................................................................ 265 Chapter 29: Measurements ................................................................................................. 271 29.1 The Ammeter ......................................................................................................... 271 29.2 The Voltmeter ........................................................................................................ 271 29.3 The Multimeter ...................................................................................................... 272 V1.2 © 2005 to 2016 SARL 7 South African Radio League Introduction to Amateur Radio 29.4 Frequency Counter ................................................................................................. 272 29.5 Power and SWR Meter .......................................................................................... 272 29.6 The Oscilloscope .................................................................................................... 273 29.7 Marker Generator ................................................................................................... 273 29.8 The Dip Meter ........................................................................................................ 273 29.9 The Dummy Load .................................................................................................. 273 29.10 The Field Strength Meter ..................................................................................... 274 29.11 The Absorption Wavemeter ................................................................................. 274 29.12 The Two-Tone Signal Generator ......................................................................... 274 Summary ........................................................................................................................ 275 Revision Questions ........................................................................................................ 276 Chapter 30: Digital Systems .............................................................................................. 279 30.1 Advantages of Digital Systems .............................................................................. 279 30.2 Principles of Digital Signal Processing .................................................................. 279 What is “Digital”? ...................................................................................................... 279 Number Systems ........................................................................................................ 280 Logic Operations ........................................................................................................ 281 Sampling .................................................................................................................... 284 Analogue to Digital Conversion ................................................................................. 285 Digital to Analogue Conversion ................................................................................. 286 30.3 Digital Filters ......................................................................................................... 286 IIR Filters ................................................................................................................... 287 FIR Filters .................................................................................................................. 288 30.4 Direct Digital Synthesis ......................................................................................... 289 30.5 The Fourier Transform ........................................................................................... 290 30.6 Convolution ............................................................................................................ 291 30.7 SDR Platforms ....................................................................................................... 291 Summary ........................................................................................................................ 291 Revision Questions ........................................................................................................ 293 Chapter 31: Digital Communication Modes ...................................................................... 296 31.1 Practical Implementation of Digital Communications ........................................... 296 31.2 Digital Modulation ................................................................................................. 296 31.3 Text Modes ............................................................................................................ 296 Morse Telegraphy ...................................................................................................... 296 Radio Teletype (RTTY) ............................................................................................. 297 AMTOR ..................................................................................................................... 297 ASCII ......................................................................................................................... 298 Packet Radio .............................................................................................................. 298 APRS .......................................................................................................................... 300 PSK31 ........................................................................................................................ 300 WSJT .......................................................................................................................... 300 CLOVER .................................................................................................................... 301 PACTOR .................................................................................................................... 301 31.4 Image Modes .......................................................................................................... 301 Facsimile .................................................................................................................... 301 Slow-Scan Television (SSTV) ................................................................................... 302 Fast-Scan Television .................................................................................................. 303 31.5 Digital Voice—The Future? ................................................................................... 303 VoIP—Voice over Internet Protocol .......................................................................... 304 Summary ........................................................................................................................ 304 Revision Questions ........................................................................................................ 305 Chapter 32: Safety Considerations ..................................................................................... 307 32.1 The Human Body ................................................................................................... 307 32.2 Mains Power Supply .............................................................................................. 307 32.3 High Voltages ........................................................................................................ 307 V1.2 © 2005 to 2016 SARL 8 South African Radio League Introduction to Amateur Radio 32.4 Lightning ................................................................................................................ 308 Revision Questions ........................................................................................................ 308 Chapter 33: Before You Go ............................................................................................... 310 33.1 Meeting the Standard ............................................................................................. 310 33.2 Writing the RAE .................................................................................................... 310 The format of the examination ................................................................................... 310 The formula sheet ....................................................................................................... 311 Answering multiple-choice questions ........................................................................ 311 Typographic conventions ........................................................................................... 312 Appendix A: Glossary of Abbreviations ............................................................................ 314 V1.2 © 2005 to 2016 SARL 9 South African Radio League Introduction to Amateur Radio Version Control Version Date Description Contributors 1.0 2005 Original version of the “Radio Amateur Author Andrew Roos Examination Manual” ZS1AN 1.1 2009 Addition of digital systems Wessel du Preez ZS5BLY Peter Hers ZS6PHD Colin de Villiers ZS6COL Ean Retief ZS1PR George Honiball ZS6NE Mark Zank ZS6YES Maarten du Preez ZS6ZY Mickey Esterhuyzen ZS5QB Rassie Erasmus ZS1YT 1.2 2016 Renamed Chris R. Burger ZS6EZ “Introduction to Amateur Radio” Added preface With valuable input from: Editorial revision and formatting Vincent Harrison ZS6BTY Rearranged chapters Colin de Villiers ZS6COL Added QSL cards and LotW Added field-effect transistors Added voltage sources and models Added description of sine function Added frequency ranges Added multi-pole filters and ringing Added practical components at RF Added light-emitting diodes Added battery capacity and recharging Added field-effect transistors Added thermionic tubes Added integrated circuits Added WSJT Added error correction Added receiver thermal noise Added Pi and T networks Added reciprocal mixing Added log-periodic arrays Added feeders, including waveguides Added VSWR Added antenna stacking and phasing Added multi-path and fading Added auroral scatter and backscatter Added propagation prediction and link budgets Added direct radiation and shielding Removed ASCII table Added convolution Added safety sections: human body, lightning Added description and use of callsigns Added emergency operations Added international regulations and IARU band plans Added glossary of abbreviations Added section numbers Added UTC and log keeping suggestions Added typographic conventions for greek letters The SARL gratefully acknowledges the American Radio Relay League’s permission to use diagrams in Chapter 30. Most of these diagrams were extracted from the ARRL book Experimental Methods in RF Design by Wes Hayward W7ZOI, Rick Campbell KK7B and Bob Larkin W7PUA. This version: 1.2.21 2016-03-07 The South African Radio League asserts its copyright of this text, 2005 to 2016. SARL, Box 1721, Strubensvallei, 1735 South Africa www.sarl.org.za V1.2 © 2005 to 2016 SARL 10