Contents at a Glance
Introduction ................................................................ 1
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Part I: Understanding the Fundamentals of Electronics... 7
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Chapter 1: What Is Electronics and What Can It Do for You? ...................................... 9
Chapter 2: Manipulating Electricity to Make Something Happen .............................. 19
Chapter 3: Meeting Up with Resistance ........................................................................ 37
Chapter 4: Getting a Charge Out of Capacitors ............................................................ 63
Chapter 5: Curling Up with Coils and Crystals ............................................................. 89
Chapter 6: The Wide World of Semiconductors ........................................................ 109
Chapter 7: Cramming Components into Chips .......................................................... 139
Chapter 8: Rounding Out Your Parts List ................................................................... 163
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Part II: Getting Your Hands Dirty ............................. 187
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Chapter 9: Setting Up Shop and Staying Safe ............................................................. 189
Chapter 10: Sussing out Schematics............................................................................ 213
Chapter 11: Constructing Circuits ............................................................................... 233
Chapter 12: Measuring and Analysing Circuits .......................................................... 255
Part III: Putting Theory into Practice ........................ 279
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Chapter 13: Exploring Some Simple Circuits .............................................................. 281
Chapter 14: Great Projects You Can Build in 30 Minutes or Less............................ 305
Part IV: The Part of Tens .......................................... 329
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Chapter 15: Ten Exciting Electronics Extras .............................................................. 331
Chapter 16: Ten Great Sources for Electronics Parts .............................................. 341
Appendix: Internet Resources .................................... 345
Index ...................................................................... 349
Table of Contents
Introduction ................................................................. 1
Why Buy This Book? ....................................................................................... 1
Why Electronics? ............................................................................................. 2
Foolish Assumptions ....................................................................................... 3
Safety Is Number 1 ........................................................................................... 3
How This Book Is Organised .......................................................................... 4
Part I: Understanding the Fundamentals of Electronics ................... 4
Part II: Getting Your Hands Dirty ......................................................... 5
Part III: Putting Theory into Practice................................................... 5
Part IV: The Part of Tens ....................................................................... 5
Icons Used in This Book ................................................................................. 6
Part I: Understanding the Fundamentals of Electronics ... 7
Chapter 1: What Is Electronics and What Can It Do for You? . . . . . . . .9
Just What Is Electronics? ................................................................................ 9
Understanding Electric Current................................................................... 10
Getting a charge out of electrons ...................................................... 10
Moving electrons in conductors ........................................................ 11
Harnessing Electricity to Do Work .............................................................. 12
Where Electrical Energy Comes From ........................................................ 12
Tapping into electrical energy ........................................................... 12
Giving electrons a nudge .................................................................... 13
Using conductors to make the circuit ............................................... 13
Oh, the Things Electrons Can Do!................................................................ 15
Creating good vibrations .................................................................... 15
Seeing is believing................................................................................ 15
Sensing and alarming .......................................................................... 16
Controlling motion............................................................................... 16
Solving problems (aka computing) ................................................... 16
Communicating with each other........................................................ 16
Chapter 2: Manipulating Electricity to Make Something Happen . . .19
Supplying Electrical Energy ......................................................................... 19
Getting direct current from a battery ............................................... 20
Using alternating current from
the power station ............................................................................. 22
Transforming light into electricity .................................................... 24
Table of Contents
Understanding Directions: Real Electron Flow
versus Conventional Current Flow .......................................................... 24
Examining a Simple Light Bulb Circuit........................................................ 25
Controlling Electrical Current with Basic Components ........................... 28
Ways to control current ...................................................................... 29
Active versus passive components ................................................... 30
Making Connections: Series and Parallel.................................................... 30
Series connections ............................................................................... 30
Parallel connections ............................................................................ 31
Combination circuits ........................................................................... 32
Creating Electronic Systems ........................................................................ 33
Making sound appear out of thin air ................................................. 33
Painting pictures with electrons ........................................................ 35
Chapter 3: Meeting Up with Resistance . . . . . . . . . . . . . . . . . . . . . . . . .37
Resisting the Flow of Current....................................................................... 37
Resistors: Passive Yet Powerful .................................................................. 39
Discovering the usefulness of resistors ............................................ 39
Choosing a type: fixed or variable ..................................................... 40
Decoding fixed resistors ..................................................................... 42
Dialling with potentiometers .............................................................. 44
Rating resistors according to power ................................................. 45
Combining Resistors ..................................................................................... 47
Using resistors in series ...................................................................... 47
Employing resistors in parallel .......................................................... 48
Combining series and parallel resistors ........................................... 50
Obeying Ohm’s Law ...................................................................................... 51
Driving current through a resistance ................................................ 51
Understanding a relationship that’s constantly proportional! ...... 52
Working with one law, three equations ............................................ 53
Using Ohm’s Law to Analyse Circuits ......................................................... 54
Calculating current through a component ....................................... 54
Working out voltage across a component ........................................ 55
Determining an unknown resistance ................................................. 56
What is Ohm’s Law Really Good For? ......................................................... 56
Analysing complex circuits ................................................................ 57
Designing and altering circuits .......................................................... 58
The Power of Joule’s Law ............................................................................. 60
Using Joule’s Law to choose components ........................................ 60
Going perfectly together: Joule and Ohm ......................................... 60
Trying Your Hand at Circuits with Resistors ............................................. 61
Chapter 4: Getting a Charge Out of Capacitors . . . . . . . . . . . . . . . . . . . .63
Reservoirs for Electrical Energy .................................................................. 63
Charging and discharging ................................................................... 64
Opposing voltage change.................................................................... 65
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Allowing alternating current ............................................................. 66
Shining a light on capacitors .............................................................. 67
Characterising Capacitors ............................................................................ 67
Calculating the charge a capacitor can store................................... 67
Reading capacitor values .................................................................... 68
Keeping an eye on the working voltage ............................................ 71
Selecting dielectrics............................................................................. 71
Sizing up capacitor packaging ............................................................ 72
Connecting with polarity .................................................................... 73
Varying capacitance ............................................................................ 74
Combining Capacitors................................................................................... 74
Capacitors in parallel .......................................................................... 74
Capacitors in series ............................................................................. 76
Understanding Capacitive Reactance ......................................................... 77
Using Ohm’s Law for capacitive reactance ...................................... 78
Understanding that behaviour depends on frequency ................... 79
So What Have Capacitors Ever Done for Us? ............................................. 80
Storing electrical energy ..................................................................... 80
Blocking DC current ............................................................................ 80
Smoothing out voltage ........................................................................ 80
Creating timers .................................................................................... 81
Tuning in (or out) frequencies ........................................................... 81
Teaming Up with Resistors .......................................................................... 81
Timing is everything ............................................................................ 81
Calculating RC time constants ........................................................... 83
Creating a timer.................................................................................... 84
Selecting Frequencies with Simple RC Filters ............................................ 85
Looking at low-pass filters .................................................................. 85
Encountering high-pass filters ........................................................... 86
Cutting off frequencies at the knees .................................................. 87
Filtering frequency bands ................................................................... 88
Trying Out Simple Capacitive Circuits........................................................ 88
Chapter 5: Curling Up with Coils and Crystals . . . . . . . . . . . . . . . . . . . .89
Working Both Ways: Magnetism and Electricity ....................................... 90
Drawing the (flux) lines with magnets .............................................. 90
Producing a magnetic field with electricity ...................................... 91
Inducing current with a magnet ......................................................... 92
Introducing the Inductor: A Coil with a Magnetic Personality ................ 93
Measuring inductance ......................................................................... 93
Opposing current changes ................................................................. 94
Alternating current gets nowhere fast .............................................. 95
Understanding Inductive Reactance .......................................................... 96
Using Ohm’s Law for inductive reactance ........................................ 97
Discovering that behaviour depends on frequency (again!) .......... 97
Table of Contents
Using Inductors in Circuits ........................................................................... 98
Insulating and shielding inductors .................................................... 98
Reading inductance values ................................................................. 98
Combining shielded inductors ........................................................... 99
Filtering signals with inductors.......................................................... 99
Calculating the RL time constant ..................................................... 100
Now Introducing Impedance! ..................................................................... 101
Tuning in to Radio Broadcasts .................................................................. 102
Resonating with RLC circuits ........................................................... 102
Ensuring crystal-clear resonance .................................................... 104
Calling on the Coil Next Door: Transformers ........................................... 105
Letting unshielded coils interact ..................................................... 105
Isolating circuits from a power source ........................................... 106
Stepping up, stepping down voltages ............................................. 106
Chapter 6: The Wide World of Semiconductors . . . . . . . . . . . . . . . . . .109
Are We Conducting, or Aren’t We? ............................................................ 109
Doping semiconductors .................................................................... 111
Combining n-types and p-types to create components ................ 111
Forming a Junction Diode ........................................................................... 113
Biasing the diode ............................................................................... 114
Conducting current through a diode .............................................. 115
Rating your diode .............................................................................. 116
Discovering what’s in a name........................................................... 116
Orientating yourself: Which way is up? .......................................... 117
Using Diodes in Circuits.............................................................................. 117
Rectifying AC ...................................................................................... 118
Regulating voltage with Zener diodes ............................................. 119
Seeing the light with LEDs ................................................................ 120
Using diodes in other ways .............................................................. 122
Trillions of Transistors ............................................................................... 123
Shrinking circuits ............................................................................... 123
Examining the anatomy of a transistor ........................................... 123
Operating a transistor ....................................................................... 125
How Transistors Really Work .................................................................... 126
Emitting and collecting electrons .................................................... 127
Gaining current .................................................................................. 129
Saturating the transistor ................................................................... 130
Using a Model to Understand Transistors ............................................... 131
Amplifying Signals with a Transistor ........................................................ 132
Turning it on ....................................................................................... 133
Turning it up ....................................................................................... 133
Turning it to your needs ................................................................... 134
Switching Signals with a Transistor .......................................................... 135
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Choosing Transistors .................................................................................. 135
Tackling transistor ratings ............................................................... 136
Identifying transistors ....................................................................... 136
Recognising transistors .................................................................... 137
Integrating Components ............................................................................ 138
Chapter 7: Cramming Components into Chips. . . . . . . . . . . . . . . . . . . .139
Discovering Integrated Circuits ................................................................. 140
Linear, Digital or Both? ............................................................................... 141
Making Decisions with Logic ...................................................................... 141
Beginning with bits ............................................................................ 142
Processing data with gates ............................................................... 144
Telling the truth ................................................................................. 146
Understanding How to Use ICs .................................................................. 147
Identifying ICs with part numbers ................................................... 147
Packaging is everything .................................................................... 147
Understanding IC pinouts ................................................................. 149
Relying on IC datasheets ................................................................... 150
Meeting Some Top Chips ............................................................................ 151
Sounding out operational amplifiers ............................................... 151
Playing with the IC time machine: the 555 timer ........................... 153
Counting on the 4017 decade counter ............................................ 159
Expanding Your IC Horizons ...................................................................... 161
Chapter 8: Rounding Out Your Parts List . . . . . . . . . . . . . . . . . . . . . . . .163
Making Connections .................................................................................... 163
Choosing wires wisely ....................................................................... 164
Plugging in to connectors ................................................................. 166
Powering Up ................................................................................................. 168
Turning on the juice with batteries ................................................. 168
Getting power from the sun.............................................................. 171
Working off your wall power (not recommended!) ....................... 172
Switching Electricity On and Off ................................................................ 173
Controlling the action of a switch.................................................... 173
Making the right contacts ................................................................. 174
Using Your Sensors ..................................................................................... 176
Seeing the light ................................................................................... 176
Capturing sound with microphones ................................................ 177
Feeling the heat .................................................................................. 178
Trying other energising input transducers .................................... 180
Sensing Something’s Going On .................................................................. 181
Speaking of speakers ......................................................................... 181
Sounding off with buzzers ................................................................ 183
Creating good vibrations with DC motors ...................................... 184
Table of Contents
Part II: Getting Your Hands Dirty .............................. 187
Chapter 9: Setting Up Shop and Staying Safe . . . . . . . . . . . . . . . . . . . .189
Picking a Place to Practise Electronics ..................................................... 190
Creating a great lab............................................................................ 190
Choosing a workbench ...................................................................... 191
Tooling Up .................................................................................................... 191
Shopping for soldering stuff ............................................................. 192
Measuring with a multimeter ........................................................... 193
Getting hands-on with hand tools.................................................... 195
Collecting cloths and cleaners ......................................................... 197
Oiling the wheels................................................................................ 198
Sticking with it .................................................................................... 198
Selecting other tools and supplies .................................................. 199
Picking up Parts ........................................................................................... 200
Practising with solderless breadboards ......................................... 200
Building a circuit-building starter kit .............................................. 202
Adding up the extras ......................................................................... 203
Organising all your parts .................................................................. 204
Protecting You and Your Electronics ....................................................... 204
Accepting that electricity can really hurt ....................................... 205
Soldering safely .................................................................................. 208
Avoiding static like the plague ......................................................... 209
Staying Safe: Safety Checklist ..................................................................... 211
Chapter 10: Sussing out Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . .213
Approaching Schematics ............................................................................ 213
Seeing the Big Picture ................................................................................. 214
Following connections ...................................................................... 215
Looking at a simple battery circuit.................................................. 216
Recognising Symbols of Power .................................................................. 217
Showing where the power is ............................................................ 218
Marking your ground ......................................................................... 220
Labelling Circuit Components ................................................................... 223
Analogue electronic components .................................................... 224
Digital logic and IC components ...................................................... 226
Odds and ends ................................................................................... 228
Exploring a Schematic................................................................................. 229
Alternative Schematic Drawing Styles ...................................................... 231
Chapter 11: Constructing Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .233
Taking a Look at Solderless Breadboards ................................................ 234
Exploring a solderless breadboard, inside and out ...................... 234
Sizing up the breadboards ................................................................ 237
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Building Circuits on Solderless Breadboards .......................................... 237
Preparing your parts and tools ........................................................ 237
Saving time with pre-stripped wires................................................ 238
Laying out your circuit ...................................................................... 239
Avoiding damaged circuits ............................................................... 241
Soldering On ................................................................................................. 242
Preparing to solder ............................................................................ 243
Soldering for success ........................................................................ 244
Inspecting the joint ............................................................................ 245
Desoldering when necessary............................................................ 246
Cooling down after soldering ........................................................... 247
Ensuring safe soldering ..................................................................... 247
Committing to a Permanent Circuit .......................................................... 248
Moving your circuit to a solder breadboard .................................. 248
Prototyping with strip boards.......................................................... 249
Wrapping with wires ......................................................................... 251
Making a custom circuit board ........................................................ 252
Chapter 12: Measuring and Analysing Circuits . . . . . . . . . . . . . . . . . .255
Multitasking with a Multimeter .................................................................. 255
It’s a voltmeter! .................................................................................. 257
Now, it’s an ammeter! ........................................................................ 257
Ohm my! It’s an ohmmeter, too!....................................................... 258
Meeting Your First Multimeter .................................................................. 258
Unpacking your digital multimeter .................................................. 260
Homing in on the range ..................................................................... 261
Setting Up Your Multimeter ....................................................................... 263
Operating Your Multimeter ........................................................................ 264
Measuring voltage.............................................................................. 265
Measuring current ............................................................................. 266
Measuring resistance ........................................................................ 268
Running other multimeter tests ....................................................... 273
Using a Multimeter to Check Your Circuits.............................................. 274
Introducing Logic Probes and Oscilloscopes .......................................... 275
Probing the depths of logic .............................................................. 275
Scoping out signals with an oscilloscope ....................................... 276
Part III: Putting Theory into Practice ......................... 279
Chapter 13: Exploring Some Simple Circuits . . . . . . . . . . . . . . . . . . . .281
Getting Equipped ......................................................................................... 281
Seeing Is Believing: Ohm’s Law Really Works! ......................................... 283
Analysing a series circuit .................................................................. 284
Dividing up voltage ............................................................................ 287
Parallel parking resistors .................................................................. 289
Table of Contents
Charging and Discharging a Capacitor ..................................................... 291
Watching your charges go up and down ........................................ 291
Varying the RC time constant .......................................................... 293
Dropping Voltages across Diodes ............................................................. 294
Turning on an LED ............................................................................. 294
Clipping voltages................................................................................ 296
Gaining Experience with Transistors ........................................................ 298
Amplifying current ............................................................................. 298
Measuring tiny currents .................................................................... 300
Creating light at your fingertip ......................................................... 300
Using Your Logic.......................................................................................... 301
Seeing the light with a logic gate ..................................................... 302
Turning three NAND gates into an OR gate .................................... 303
Chapter 14: Great Projects You Can Build in 30 Minutes or Less . . .305
What to Get and Where to Get It ............................................................... 305
Building Brilliant, Blinking, Bright Lights ................................................. 306
Following the 555 fast flasher ........................................................... 306
Gathering parts for the LED flasher ................................................. 310
Putting the Squeeze on with Piezoelectricity .......................................... 310
Experimenting with piezoelectricity ............................................... 311
Getting the parts for the piezoelectric circuit ............................... 313
Assembling the Amazing See-in-the-Dark Infrared Detector .................. 313
Searching for infrared light............................................................... 314
Tracking down parts for the infrared detector .............................. 315
Keeping People Away with a Siren! ........................................................... 315
Making your siren sound .................................................................. 316
Sorting the siren parts list ................................................................ 317
Lighting the Way with an Electronic Compass ........................................ 317
Checking under the compass bonnet.............................................. 317
Locating your electronic compass parts ........................................ 319
Alarming Way to Sense the Light............................................................... 320
Making your alarm work for you...................................................... 320
Assembling a light alarm parts list .................................................. 321
’Lil but Loud Amp ........................................................................................ 321
Making Music with a Melody Maker .......................................................... 322
Building the Pocket Water Tester ............................................................. 323
Understanding how the water tester works ................................... 323
Gathering water tester parts ............................................................ 324
Generating Cool Lighting Effects ............................................................... 325
Arranging the LEDs ............................................................................ 325
Chasing down the parts .................................................................... 327
Making an Electronic Die ............................................................................ 327
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Part IV: The Part of Tens ........................................... 329
Chapter 15: Ten Exciting Electronics Extras . . . . . . . . . . . . . . . . . . . . .331
Trying Out Ready-Made Electronics Kits ................................................. 331
Varying Your Voltage .................................................................................. 332
Counting Up Those Megahertz .................................................................. 332
Generating All Kinds of Signals .................................................................. 334
Sweeping Frequencies Up and Down ........................................................ 334
Taking the Pulse .......................................................................................... 335
Analysing Your Logic .................................................................................. 336
Simulating with Software ............................................................................ 336
Buying Testing Tool Deals .......................................................................... 338
Boxing Your Tricks – With Knobs On ....................................................... 339
Chapter 16: Ten Great Sources for Electronics Parts . . . . . . . . . . . . .341
Buying British: Suppliers within the UK ................................................... 341
Maplin .................................................................................................. 341
RS Components .................................................................................. 342
Farnell .................................................................................................. 342
RSH Electronics .................................................................................. 342
Bitsbox ................................................................................................ 343
ESR Electronic Components ............................................................. 343
Ordering from across the Pond ................................................................. 343
Digikey ................................................................................................. 343
All Electronics .................................................................................... 344
B.G. Micro ........................................................................................... 344
Mouser Electronics ............................................................................ 344
Appendix: Internet Resources .................................... 345
Finding Guides and Advice ......................................................................... 345
Working Things Out with Calculators ....................................................... 346
Surfing for Circuits ...................................................................................... 346
Asking Questions in Discussion Forums .................................................. 347
Getting Things Surplus ............................................................................... 348
Index ....................................................................... 349