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| Preface | |
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| Introduction to the EMI Problem | |
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| Electrical and Electromagnetic Fundamentals | |
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| What Is Electricity? | |
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| Positive and Negative Electricity | |
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| Electronic Model of the Atom | |
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| The Bohr Model of the Atom | |
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| Electron Shells | |
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| Electron Subshells and Electron Spin | |
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| Electron Valence and Free Electrons | |
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| Conductors, Insulators, and Semiconductors | |
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| The Unit of Electric Charge | |
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| Electrical Polarities | |
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| Millikan's Oil Drop Experiment | |
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| Electrical Potential | |
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| Electrical Current and Its Units | |
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| Electrical Current vs Electrical Charge | |
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| Types of Current Flow | |
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| Resistance to Electrical Current | |
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| Conductance | |
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| Current Flow Direction | |
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| Electrical Power | |
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| Electrical Sources | |
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| The Electromagnetic Field | |
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| Sources of Electromagnetic Interference | |
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| Fundamentals of Electromagnetic Interference | |
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| Fundamental Causes of EMI | |
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| The Antenna | |
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| Modes of Entry | |
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| Differential-Mode vs Common-Mode Signals | |
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| Equipment Design Considerations | |
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| Radio-Frequency Radiation | |
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| Near Fields and Far Fields | |
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| Grounding Methods for RF Systems | |
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| Schematic Symbols | |
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| Different Grounds | |
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| Grounding Systems | |
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| Ground Designs | |
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| Other Ground Electrodes | |
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| Installing Ground Rods | |
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| Tower Grounding | |
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| Vertical Antenna Counterpoise Grounds ("Radials") | |
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| Conclusion | |
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| Shielding Electronic Circuits | |
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| Approaches to Shielding | |
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| Skin Effect and Skin Depth | |
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| Ground Planes | |
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| Shielded Boxes | |
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| Holes in Shields | |
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| Double Shielding | |
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| Multicompartment Shielding | |
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| Spray-On Shielding | |
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| Connectors, Meters, and Dials | |
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| Installing a Coaxial Connector | |
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| Guard Shielding | |
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| Grounding and Ground Loops | |
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| Filtering Electronic Circuits | |
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| Shielding | |
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| Basic Types of Filters | |
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| Filter Circuits | |
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| R-C EMI/RFI Protection | |
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| Feedthrough Capacitors | |
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| Notch Filtering | |
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| Twin-Tee Notch Filter Networks | |
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| Active Twin-Tee Notch Filters | |
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| Adjustable Bridged-Tee Circuits | |
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| Gyrator Circuits | |
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| General Guidelines | |
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| Conclusion | |
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| AC Power-Line and Electrical Device EMI | |
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| 120/240 Volt Electrical System | |
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| Noise | |
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| Regulatory/Legal Issues | |
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| Corona and Spark | |
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| Safety | |
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| Locating EMI Sources | |
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| Filter Solution | |
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| Electric Motors | |
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| Common-Mode Filtering | |
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| Controlling Transmitter Spurious Emissions | |
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| Types of Transmitter | |
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| Operating the Transmitter | |
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| What to Do? | |
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| Be Wary! | |
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| Transmitter Test Setup | |
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| Third-Harmonic or Higher | |
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| VHF and Up Transmitters | |
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| Telephones and EMI | |
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| The Federal Communications Commission | |
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| The Telephone Company | |
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| The Radio Owner | |
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| The Telephone Manufacturer | |
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| The Telephone Owner | |
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| Technical Issues | |
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| Twisted Pair, Flat (Parallel), and Shielded Wiring | |
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| Common Mode vs Differential Mode | |
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| Resonances | |
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| Telephone Ground | |
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| Corrosion | |
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| Substandard Wiring | |
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| Telephone Classification | |
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| Telephone Registration Numbers | |
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| Capacitors | |
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| Common-Mode RF Chokes | |
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| Filtering | |
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| Noise Cancellation Bridges | |
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| A Simple Bridge Circuit | |
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| A Different Bridge | |
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| Conclusion | |
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| Locating EMI Sources | |
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| RF Sleuthing Tools | |
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| RF Detectors | |
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| Radio Direction Finding | |
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| Field Improvisation | |
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| Regular Loop Antennas | |
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| Sense Antenna Circuit | |
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| Switched Pattern RDF Antennas | |
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| EMI to Television, Cable TV, and VCR Equipment | |
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| The Basic Television Receiver | |
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| Fundamental Overload | |
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| Harmonic Overload | |
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| Audio Rectification | |
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| IMD Interference | |
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| IF Interference | |
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| Direct Pickup | |
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| Common-Mode vs Differential-Mode Signals | |
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| Common-Mode Filters | |
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| Filtering | |
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| Stubs for EMI Elimination | |
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| Faraday Shielded Coaxial Cable | |
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| Cable Television Systems | |
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| Two-Way CATV | |
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| Channelization | |
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| Leakage | |
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| Responsibility | |
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| Finding Leaks | |
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| What to Do When the Interference Is at the Subscriber End | |
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| What to Do When the Customer Is at Fault | |
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| VCRs | |
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| EMI to Consumer Electronics | |
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| Roles and Responsibilities | |
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| The Source of the Problem | |
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| Typical Audio System | |
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| Pathways for Trouble | |
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| Troubleshooting | |
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| Cures | |
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| Shielding | |
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| Grounding | |
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| EMI from Computers | |
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| The Law | |
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| The Problems with Computers | |
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| Cabinetry | |
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| Troubleshooting Computer EMI | |
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| The Role of Ferrite Chokes | |
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| Ground Loops | |
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| EMI to Computers | |
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| Mystery EMI: Rusty Downspouts and All That | |
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| Moodie and the Crown Vickie | |
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| The High Hum Level--FM Broadcasting Station | |
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| The Slack Coax Caper | |
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| Lesson Learned: Don't Complain Too Loudly | |
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| Rusty Downspouts | |
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| Radio Receiver Basics | |
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| Signals, Noise, and Reception | |
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| Thermal Noise | |
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| The Reception Problem | |
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| Strategies | |
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| Radio Receiver Specifications | |
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| Origins | |
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| Superheterodyne Receivers | |
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| Receiver Performance Factors | |
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| Units of Measure | |
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| Noise | |
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| Signal-to-Noise Ratio (SNR or S[subscript n]) | |
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| Noise Factor, Noise Figure, and Noise Temperature | |
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| Noise in Cascade Amplifiers | |
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| Receiver Noise Floor | |
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| Static Measures of Receiver Performance | |
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| Sensitivity | |
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| Selectivity | |
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| Stability | |
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| AGC Range and Threshold | |
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| Dynamic Performance | |
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| Intermodulation Products | |
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| -1 dB Compression Point | |
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| Third-Order Intercept Point | |
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| Dynamic Range | |
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| Blocking | |
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| Cross-Modulation | |
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| Reciprocal Mixing | |
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| IF Notch Rejection | |
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| Internal Spurii | |
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| Dealing with Radio Receiver System EMI | |
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| Intermod Hill: A Tale of Woe | |
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| The Problem | |
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| The Attenuator Solution | |
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| The Antenna Solution | |
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| The Filter Solution | |
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| Transmission Line Stubs | |
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| Shielding | |
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| Expected Results | |
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| Difficult Cases | |
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| The Solutions | |
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| Electrostatic Discharge (ESD) | |
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| ESD Effects | |
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| Identification by Class | |
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| ESD Control Procedures | |
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| Work Areas | |
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| Protective Flooring | |
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| Workbenches | |
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| Equipment | |
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| Clothing | |
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| ESD-Protective Materials | |
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| Regulatory Issues | |
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| Anechoic Chambers and OATS | |
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| Screened Rooms | |
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| Automotive Interference Solutions | |
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| ARRL Technical Information Service Information on Automobile-Radio Interference (Both Ways) | |
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| Automotive Interference Problems: What the Manufacturers Say | |
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| Wheels Start to Turn | |
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| ARRL Surveys Auto Manufacturers | |
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| What the Manufacturers Say | |
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| By Ed Hare, W1RFI, ARRL Laboratory Supervisor | |
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| FDA Documents on EMI | |
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| CDRH Medical Device Electromagnetic Compatibility Program | |
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| Typical Electromagnetic Environment for Medical Devices | |
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| CDRH Medical Device Electromagnetic Compatibility Program | |
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| Medical Devices and EMI: The FDA Perspective | |
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| The EMI Problem | |
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| The Complexity of Device EMI | |
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| FDA Concern with EMI | |
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| Formation of the CDRH EMC Working Group | |
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| Plans for Device EMC | |
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| Research and Standards | |
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| Work with Other Agencies | |
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| Some Accomplishments to Date | |
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| Summary | |
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| References | |
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| Electromagnetic Interference (EMI) Testing of Medical Devices | |
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| New Documents Available to Help Resolve Medical Device EMC Problems | |
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| Index | |