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Fluke DSP-2000, DSP-100 user manual Sources of Electrical Noise

Models: DSP-2000 DSP-100

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DSP-100/2000

Users Manual

Noise

Electrical noise is unwanted electrical signals that alter the shape of the signals transmitted on a LAN cable. Figure 7-5 shows an example of how noise affects the shape of an electrical signal known as a sine wave. Signals that are severely distorted by noise can cause communication errors in a LAN.

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Figure 7-5. Sources of Electrical Noise

Electrical noise is generated by any device that uses or generates voltages that vary over time. Varying voltage generates a varying electromagnetic field, which transmits noise to nearby devices in the same way that a radio transmitter transmits signals to your radio. For example, fluorescent lights, which use 50 or 60 Hz ac (alternating current) power, continuously radiate a 50 or 60 Hz signal that can be received by nearby devices as electrical noise.

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Fluke DSP-2000, DSP-100 user manual Sources of Electrical Noise

Contents

DSP-100/2000 Limited Warranty & Limitation of Liability Table of Contents DSP-100/2000 Appendices DSP-100/2000 List of Tables Tests Run per Test Standard During an Autotest List of Figures Plot of NEXT, Attenuation, and the Resulting ACR Overview of Features IntroductionDSP-100/2000 Standard Accessories Standard Accessories Using This Manual DSP-100/2000 Safety and Operational Information International Electrical SymbolsDSP-100/2000 Quick Start Powering the Test ToolUsing the Menus KeySetup Setting Quick ConfigurationQuick Configuration Settings Description Press ! Choice Results within Accuracy Range Asterisk and Test Tool AccuracyAutotest on Twisted Pair Cable Horizontal Cross Connect Blocks Meters Getting Started Autotest on Coaxial Cable Autotest on Coaxial Cable Main Unit Features DSP-100 DSP-2000Feature Main Unit Features DescriptionRemote Features Standard and Smart Remote FeaturesRemote Features Remote Connectors and FeaturesStrap and Bail Rotary SwitchOff Autotest Single Test MonitorSetup Special Functions Turning On the Test ToolPrint Smart Remote Model DSP-100Selecting a Language for Displays and Reports Performing a Self-TestNoise Test Configuring the Test ToolOvervoltage Test Controlling the BacklightAdjusting the Display Contrast Selecting a Power Line Filter FrequencySelecting an Average Cable Temperature Selecting a Test Standard and Cable TypeSelecting a Conduit Setting Selecting a Length Unit Selecting a Numeric FormatSetting the Date and Time Setting the Power-Down Timer Enabling or Disabling the Audible TonesRemote Lights, Messages, and Audible Tones Remote End Testing Smart Remote ReadyRemote Communication Error Battery StatusBattery Status Display Autotest Autotest SoftkeysSmart Autotest Automatic Diagnostics Model DSP-2000 Link Performance Grade Result HeadroomAutomatic Diagnostics Model DSP-2000 Wire Map Test Autotest Results for Twisted Pair CableAutotest Results for Twisted Pair Cable Resistance LengthPropagation Delay and Delay Skew Characteristic ImpedanceAttenuation Items on the Attenuation Results Screen DescriptionGc10c.eps Next Test Items on the Next Results Screen DescriptionNext Plot Screen Items on the Next Plot Screen Description ACR Items on the ACR Results Screen Description ACR Plot Screen Items on the ACR Plot Screen Description Return Loss RL Items on the RL Results Screen DescriptionRL@REMOTE Model DSP-2000 Psnext Power Sum Next Model DSP-2000 Connector Autotest Results for Coaxial Cable Anomaly No ReflectionSaving Autotest Results Gc15c.eps Automatically Incrementing the Cable Identification Name Autotest ReportIf Memory is Full Part of an Autotest Report for Twisted Pair 10. Autotest Report for Coaxial Cable DSP-100/2000 Running Individual Tests Single Tests for Twisted Pair CableWhen to Use a Remote Unit Scanning FunctionTest Remote Requirements for Cable Tests Remote UnitRunning a Single Test on Twisted Pair Cable Running Individual Tests TDX Analyzer Running the TDX AnalyzerTDX Analyzer Results Items on the TDX Analyzer Results ScreenTDX Analyzer Plot How to Terminate the Cable TDR TestRunning the TDR Test on Twisted Pair Cable Running the TDR Test on Coaxial CableTDR Plot Screen TDR Results ScreenItems on a TDR Results Screen Twisted Pair Results Single Test Results for Twisted Pair Cable Next and NEXT@REMOTE Wire MapImpedance Return Loss RL and RL@REMOTE Single Tests for Coaxial CableRunning a Single Test on Coaxial Cable Single Tests for Coaxial Cable Monitoring Network Activity Single Test Results for Coaxial CableMonitoring Network Activity DSP-100/2000 Items on the Traffic Monitor Screen Description Monitoring Impulse Noise Identifying Hub Port ConnectionsChanging the Impulse Noise Threshold Running the Impulse Noise Test Use Dto highlight Impulse Noise on RJ45 Noise Test Results Determining Hub Port Capabilities Model DSP-2000Items on the Noise Monitor Screen Description Using the Tone Generator Model DSP-2000 Viewing and Printing Saved Reports Printing Test ReportsPrinter Interface Cable Configuring the Serial PortPrinting Viewing and Printing Saved Reports Printing Test Reports DSP-100/2000 If the Printer Does Not Respond Viewing, Renaming, and Deleting Test Reports Calibrations and Custom Test Standards Calibrating the Test ToolConnections for Self-Calibration DSP-2000 Shown NVP Calibration Use Dto highlight Determine Cable NVPConfiguring a Custom Cable Page DSP-100/2000 Basic Cable Testing LAN Cable ConstructionTwisted Pair Cable Twisted Pair Cable Construction568A Coaxial Cable Coaxial Cable ConstructionAttenuation of a Signal AttenuationNoise Sources of Electrical NoiseCharacteristic Impedance Minimizing Impedance Discontinuities Locating Next Problems Crosstalk and Near-End Crosstalk NextA TDX Analyzer Plot Basic Cable Testing Incorrect Wiring Split Pair Split Pairs and NextMinimizing Crosstalk Nominal Velocity of Propagation NVP NVP and Length MeasurementsTime Domain Reflectometry TDR NVP CalibrationReflections from Opens ShortReflections from Shorts Reflections from Other DiscontinuitiesCable Termination Interpreting the TDR PlotACR Limit in dB Frequency in MHzTroubleshooting Basics Finding Cable FaultsIdentifying Cable Faults Likely Causes of Failure Test FailureIdentifying Cable Faults Examples of Test Displays and Plots Identifying Cable Faults Test Failure Next test fails Impedance anomaly is Detected DSP-100/2000 Maintenance Cleaning and StorageReplacing the NiCad Battery Pack Removing the Battery in the Standard RemoteInternal Lithium Backup Battery Removing the NiCad Battery PackService Center Repair If the Test Tool FailsSymptom 3 Test results appear to be incorrect Troubleshooting the Test Tool Symptom 1 Display is blankSymptom 2 Remote unit is not detected Symptom 6 Self calibration failsReplacement Parts Description Replacement PartsPart Number Self-Calibration Period SpecificationsService Center Calibration Period Compatibility with Remote UnitsTest Standards Cable Types TestedTime for Autotest Propagation Delay Test Specifications Propagation Delay TestLength Test Specifications Length TestDC Loop Resistance NextTDR Specifications for Cables 100m 328 ft TDX Analyzer Specifications for Cables 100m 328 ftReturn Loss Model DSP-2000 LAN Traffic Impulse NoiseModel DSP-100 LAN Traffic Serial InterfacePC Interface Cable 25-pin ConnectorPC Interface Cable Connections Test Tool End DB9S female Power Environmental RequirementsOperating Environment Specifications Input RatingsCertifications DimensionsWeight MemoryWarranty RJ45 ConnectorDisplay DSP-100/2000 Appendices Page Using DSP-LINK IntroductionConnecting to a PC Installing DSP-LINKPreparing for Data Transfer Configuring the Serial Ports Figure A-1. Connecting the Test Tool to a PCCommunication Problems DSP-LINK Functions Detailed Test Data Quick PlotDSP-100/2000 Formatting Hints for Uploaded Reports Table A-3. Formats for Uploaded Reports Courier Point SizeGetting Software Updates from Fluke Downloading New Test Standards Downloading New Software 10BaseT 10Base2100BaseTX Auto-Negotiation Baseband SignalingBroadband Signaling BandwidthCollision CapacitanceChannel Crossed PairDownload CrosstalkCSV Data EIA 568AHorizontal Cross-Connect Hardware Flow ControlHorizontal Cabling Impedance DiscontinuityNear-End Crosstalk Next Propagation DelayLink Pulse PacketRunt Packet Reversed PairRJ45 Screened Twisted Pair ScTPTerminator Split PairTDXä Token RingXON/XOFF Flow Control DSP-100/2000 Tests Run per Test Standard During an Autotest Next Prop. Return Loss Delay2 Delay Skew2 Tests Run per Test Standard During an Autotest CTP-PMD Prop Delay2 Delay Skew2 Return LossDSP-100/2000 Index DSP-LINK Next DSP-100/2000 Index DSP-100/2000 Manual Supplement Change #1 Wire Map Condition Wire Map Displays Displayed Schematic DescriptionWire map display showing an open on pair 1 Wire map display showing a split pair on pairs 1, 2 and 3 Change #3