도서 정보
도서 상세설명
Preface xi
Chapter 1 Introduction to the EMI Problem 1
Chapter 2 Electrical and Electromagnetic Fundamentals 5
What Is Electricity? 5
Positive and Negative Electricity 5
Electronic Model of the Atom 6
The Bohr Model of the Atom 7
Electron Shells 8
Electron Subshells and Electron Spin 9
Electron Valence and Free Electrons 9
Conductors, Insulators, and Semiconductors 10
The Unit of Electric Charge 11
Electrical Polarities 11
Millikan\'s Oil Drop Experiment 13
Electrical Potential 13
Electrical Current and Its Units 15
Electrical Current vs Electrical Charge 15
Types of Current Flow 15
Resistance to Electrical Current 16
Conductance 17
Current Flow Direction 17
Electrical Power 18
Electrical Sources 18
The Electromagnetic Field 19
Sources of Electromagnetic Interference 21
Chapter 3 Fundamentals of Electromagnetic Interference 23
Fundamental Causes of EMI 23
The Antenna 24
Modes of Entry 24
Differential-Mode vs Common-Mode Signals 25
Equipment Design Considerations 26
Radio-Frequency Radiation 26
Near Fields and Far Fields 27
Chapter 4 Grounding Methods for RF Systems 29
Schematic Symbols 29
Different Grounds 30
Grounding Systems 33
Ground Designs 34
Other Ground Electrodes 37
Installing Ground Rods 41
Tower Grounding 43
Vertical Antenna Counterpoise Grounds (\"Radials\") 43
Conclusion 46
Chapter 5 Shielding Electronic Circuits 47
Approaches to Shielding 49
Skin Effect and Skin Depth 50
Ground Planes 51
Shielded Boxes 52
Holes in Shields 53
Double Shielding 55
Multicompartment Shielding 55
Spray-On Shielding 55
Connectors, Meters, and Dials 55
Installing a Coaxial Connector 57
Guard Shielding 58
Grounding and Ground Loops 62
Chapter 6 Filtering Electronic Circuits 65
Shielding 65
Basic Types of Filters 65
Filter Circuits 67
R-C EMI/RFI Protection 69
Feedthrough Capacitors 70
Notch Filtering 72
Twin-Tee Notch Filter Networks 73
Active Twin-Tee Notch Filters 74
Adjustable Bridged-Tee Circuits 76
Gyrator Circuits 77
General Guidelines 78
Conclusion 79
Chapter 7 AC Power-Line and Electrical Device EMI 81
120/240 Volt Electrical System 82
Noise 83
Regulatory/Legal Issues 83
Corona and Spark 84
Safety 85
Locating EMI Sources 85
Filter Solution 85
Electric Motors 86
Common-Mode Filtering 86
Chapter 8 Controlling Transmitter Spurious Emissions 89
Types of Transmitter 89
Operating the Transmitter 93
What to Do? 96
Be Wary! 99
Transmitter Test Setup 99
Third-Harmonic or Higher 100
VHF and Up Transmitters 101
Chapter 9 Telephones and EMI 103
The Federal Communications Commission 103
The Telephone Company 103
The Radio Owner 104
The Telephone Manufacturer 104
The Telephone Owner 104
Technical Issues 104
Twisted Pair, Flat (Parallel), and Shielded Wiring 105
Common Mode vs Differential Mode 106
Resonances 106
Telephone Ground 106
Corrosion 106
Substandard Wiring 106
Telephone Classification 107
Telephone Registration Numbers 107
Capacitors 107
Common-Mode RF Chokes 107
Filtering 108
Chapter 10 Noise Cancellation Bridges 113
A Simple Bridge Circuit 116
A Different Bridge 119
Conclusion 119
Chapter 11 Locating EMI Sources 121
RF Sleuthing Tools 121
RF Detectors 125
Radio Direction Finding 126
Field Improvisation 130
Regular Loop Antennas 130
Sense Antenna Circuit 131
Switched Pattern RDF Antennas 132
Chapter 12 EMI to Television, Cable TV, and VCR Equipment 135
The Basic Television Receiver 135
Fundamental Overload 137
Harmonic Overload 137
Audio Rectification 137
IMD Interference 137
IF Interference 138
Direct Pickup 138
Common-Mode vs Differential-Mode Signals 138
Common-Mode Filters 138
Filtering 139
Stubs for EMI Elimination 140
Faraday Shielded Coaxial Cable 140
Cable Television Systems 141
Two-Way CATV 142
Channelization 142
Leakage 142
Responsibility 142
Finding Leaks 142
What to Do When the Interference Is at the Subscriber End 143
What to Do When the Customer Is at Fault 143
VCRs 143
Chapter 13 EMI to Consumer Electronics 145
Roles and Responsibilities 145
The Source of the Problem 146
Typical Audio System 146
Pathways for Trouble 147
Troubleshooting 147
Cures 148
Shielding 149
Grounding 149
Chapter 14 EMI from Computers 151
The Law 151
The Problems with Computers 151
Cabinetry 153
Troubleshooting Computer EMI 154
The Role of Ferrite Chokes 154
Ground Loops 155
EMI to Computers 155
Chapter 15 Mystery EMI: Rusty Downspouts and All That 157
Moodie and the Crown Vickie 157
The High Hum Level--FM Broadcasting Station 158
The Slack Coax Caper 158
Lesson Learned: Don\'t Complain Too Loudly 159
Rusty Downspouts 161
Chapter 16 Radio Receiver Basics 163
Signals, Noise, and Reception 163
Thermal Noise 164
The Reception Problem 165
Strategies 165
Radio Receiver Specifications 166
Origins 166
Superheterodyne Receivers 168
Receiver Performance Factors 172
Units of Measure 172
Noise 173
Signal-to-Noise Ratio (SNR or S[subscript n]) 176
Noise Factor, Noise Figure, and Noise Temperature 176
Noise in Cascade Amplifiers 177
Receiver Noise Floor 178
Static Measures of Receiver Performance 178
Sensitivity 178
Selectivity 182
Stability 186
AGC Range and Threshold 186
Dynamic Performance 187
Intermodulation Products 187
-1 dB Compression Point 188
Third-Order Intercept Point 189
Dynamic Range 191
Blocking 192
Cross-Modulation 192
Reciprocal Mixing 194
IF Notch Rejection 194
Internal Spurii 195
Chapter 17 Dealing with Radio Receiver System EMI 197
Intermod Hill: A Tale of Woe 198
The Problem 199
The Attenuator Solution 202
The Antenna Solution 202
The Filter Solution 203
Transmission Line Stubs 207
Shielding 207
Expected Results 208
Difficult Cases 208
The Solutions 208
Chapter 18 Electrostatic Discharge (ESD) 209
ESD Effects 211
Identification by Class 211
ESD Control Procedures 212
Work Areas 212
Protective Flooring 212
Workbenches 212
Equipment 213
Clothing 213
ESD-Protective Materials 213
Chapter 19 Regulatory Issues 215
Anechoic Chambers and OATS 216
Screened Rooms 218
Appendix A Automotive Interference Solutions 219
ARRL Technical Information Service Information on Automobile-Radio Interference (Both Ways) 219
Automotive Interference Problems: What the Manufacturers Say 219
Wheels Start to Turn 221
ARRL Surveys Auto Manufacturers 221
What the Manufacturers Say 223
By Ed Hare, W1RFI, ARRL Laboratory Supervisor 230
Appendix B FDA Documents on EMI 235
CDRH Medical Device Electromagnetic Compatibility Program 235
Typical Electromagnetic Environment for Medical Devices 235
CDRH Medical Device Electromagnetic Compatibility Program 235
Medical Devices and EMI: The FDA Perspective 235
The EMI Problem 236
The Complexity of Device EMI 236
FDA Concern with EMI 237
Formation of the CDRH EMC Working Group 237
Plans for Device EMC 238
Research and Standards 239
Work with Other Agencies 239
Some Accomplishments to Date 240
Summary 241
References 241
Electromagnetic Interference (EMI) Testing of Medical Devices 243
New Documents Available to Help Resolve Medical Device EMC Problems 246
Index 249