Tektronix Telescope 1502C Manual do Utilizador Página 1

User Manual1502CMetallic Time-Domain Reflectometer070-7169-05This document applies for firmware version 5.04and above.www.tektronix.com

Table of Contentsvi1502C MTDR User ManualList of TablesTable i: Shipping Carton Test Strength ix. . . . . . . . . . . . . . . . . . . . . . . . Table

Appendix B: Operator Performance ChecksB–121502C MTDR User ManualIf the instrument failed Jitter or Risetime checks, it is probably still adequate for

1502C MTDR User ManualC–1Appendix C: Operator TroubleshootingFor assistance in troubleshooting, use the following flow chart to determine ifyou have a

Appendix C: Operator TroubleshootingC–21502C MTDR User ManualPreset front panel andturn thepower on.Isthere agreed display?YESNOIs thepower source aba

Appendix C: Operator Troubleshooting1502C MTDR User ManualC–3Error MessagesAny time the instrument displays an error message, the troubleshootingproce

Appendix C: Operator TroubleshootingC–41502C MTDR User ManualAt power on during initialization only.The instrument expects the pulse height to be slig

Appendix C: Operator Troubleshooting1502C MTDR User ManualC–5At power on during initialization only.The instrument changed the gain while adjusting th

Appendix C: Operator TroubleshootingC–61502C MTDR User Manualerrors, which means that no measurements should be made with this instrumentbefore it is

1502C MTDR User ManualD–1Appendix D: Application NotePulse Echo Testing of Electrical Transmission LinesUsing the Tektronix Time-Domain Reflectometry

Appendix D: Application NoteD–21502C MTDR User ManualRelationshipsZO= (138 / pκ )* (log10 D / d) for coaxial cable%= r *100VSWR = (1 + r) + (1 – r) fo

Appendix D: Application Note1502C MTDR User ManualD–3NOTE. The relationship between % holds only when the loss is a single imped-ance discontinuity wi

1502C MTDR User ManualviiGeneral InformationThe Tektronix 1502C Metallic Time-Domain Reflectometer (MTDR) is ashort-range cable tester capable of find

Appendix D: Application NoteD–41502C MTDR User ManualPercent Reflected Voltage vs. Characteristic Line Impedance (50 or 75 ohm Source)To find the char

Appendix D: Application Note1502C MTDR User ManualD–5If the reflection is downward from the 50 W or 75 W reference level, set thereference level to th

Appendix D: Application NoteD–61502C MTDR User ManualPercent Reflected Voltage vs. Load ResistanceTo find the terminating load resistance (RL) of a li

Appendix D: Application Note1502C MTDR User ManualD–7You should note that the peak level of any reflection that does not have adiscernable plateau mig

Appendix D: Application NoteD–81502C MTDR User ManualDielectric Constant vs. Velocity FactorDielectric Constant and Velocity Factor appear on two iden

Appendix D: Application Note1502C MTDR User ManualD–9Time vs. Long Distances, in Meters or Feet (any dielectric)Distances to or between discontinuitie

Appendix D: Application NoteD–101502C MTDR User Manual

1502C MTDR User ManualGlossary–1GlossaryAberrationsImperfections or variations from a desired signal. In TDRs, a pulse ofelectrical energy is sent out

GlossaryGlossary–21502C MTDR User ManualCharacteristic ImpedanceCables are designed to match the source and load for the electrical energythat they ca

Glossary1502C MTDR User ManualGlossary–3Impedance MismatchA point in a cable or system where the incident electrical energy is redistrib-uted into abs

General Informationviii1502C MTDR User ManualInstallation and RepackingBefore unpacking the 1502C from its shipping container or carton, inspect forsi

GlossaryGlossary–41502C MTDR User Manualmeans that each division is 0.5 rho (500 millirho). A pulse set to be fourdivisions high would make each divis

Glossary1502C MTDR User ManualGlossary–5Return LossThe amount of energy reflected or returned from a cable indicates how muchthe impedance in the syst

GlossaryGlossary–61502C MTDR User Manualdenote changes resulting from environmental influences, such as tempera-ture, humidity, vibration, and shock.T

1502C MTDR User ManualIndex–1IndexAAC (see Power), xiiAccessories, 3–2Optional, 3–2Standard, 3–2accessories, standard, 3–2Address, Tektronix, xAltitud

IndexIndex–21502C MTDR User ManualIIndicators, 1–6Inspection, viiiLList of Figures, iiiList of Tables, viLoss, 1–18MMaintenance, C–1, D–1Manual Change

Index1502C MTDR User ManualIndex–3Source, viiiVoltage Rating, 1–2Voltage Selector, 1–2Voltages, 1–1Product Description, viiProduct support, contact in

IndexIndex–41502C MTDR User Manual

General Information1502C MTDR User ManualixTable i: Shipping Carton Test Strength Gross Weight (lb) Carton Test Strength (lb)0 – 10 20011 – 30 27531 –

General Informationx1502C MTDR User Manual

1502C MTDR User ManualxiGeneral Safety SummaryThe safety information in this summary is for operating personnel. Specificwarnings and cautions will be

General Safety Summaryxii1502C MTDR User ManualThis product is intended to operate from a power source that will not apply morethan 250 volts RMS betw

General Safety Summary1502C MTDR User ManualxiiiTektronix Factory Service will accept 1502C batteries for recycling. If youchoose to return the batter

General Safety Summaryxiv1502C MTDR User Manual

1502C MTDR User Manual1–1Operating InstructionsOverviewThe 1502C front panel is protected by a watertight cover, in which the standardaccessories are

Copyright © Tektronix, Inc. All rights reserved.Tektronix products are covered by U.S. and foreign patents, issued and pending. Information in this pu

Operating Instructions1–21502C MTDR User ManualREMOVECAP TOREPLACEFUSEREMOVECAP TOSELECTVOLTAGEVoltageSelectorLine FuseAC PowerCord ReceptacleFigure 1

Operating Instructions1502C MTDR User Manual1–3The battery pack will charge fully in 16 hours when the instrument is connected,via the power cord, to

Operating Instructions1–41502C MTDR User ManualProtection circuits in the charger prevent deep discharge of the batteries duringinstrument operation.

Operating Instructions1502C MTDR User Manual1–5Preparing to Use the 1502CCheck the power requirements, remove the front cover, and you are ready to te

Operating Instructions1–61502C MTDR User ManualDisplayOFFOFFOFFON1 avg500 mr 0.2 ftac0.00 ftPowerTypeWaveform CursorFront-Panel to CursorDistance Wind

Operating Instructions1502C MTDR User Manual1–7Front-Panel Controls1. CABLE: A female BNC connector for attaching a cable to the 1502C fortesting.2. N

Operating Instructions1–81502C MTDR User Manualupper right corner of the LCD, showing the distance from the front panelBNC to the current cursor locat

Operating Instructions1502C MTDR User Manual1–9d. Finding Unknown Vp Values describes a procedure for finding anunknown Vp.4. Setup Menu controls the

Operating Instructions1–101502C MTDR User Manualii. Noise Diagnostic measures the internal RMS noise levels of theinstrument.iii. Offset/Gain Diagnost

Operating Instructions1502C MTDR User Manual1–116. View Stored Waveform Settings displays the instrument settings for thestored waveform.7. Option Por

WARRANTYTektronix warrants that the products that it manufactures and sells will be free from defects in materials andworkmanship for a period of one

Operating Instructions1–121502C MTDR User ManualTest PreparationsVp is the speed of a signal down the cable given as a percentage of the speed oflight

Operating Instructions1502C MTDR User Manual1–13The following three illustrations show settings too low, too high, and correct fora sample three-foot

Operating Instructions1–141502C MTDR User ManualCable Test ProcedureBe sure to read the previous paragraphs on Vp.1. Set the 1502C controls:POWER OnCA

Operating Instructions1502C MTDR User Manual1–15OFFOFFOFFONac 20.000 ftShortFigure 1–9: Short in the CableWhen the entire cable is displayed, you can

Operating Instructions1–161502C MTDR User ManualOFFOFFOFFONac 452.000 ftOpenFigure 1–11: 455-ft Cable5. Change DIST/DIV to 20 ft/div. The entire cable

Operating Instructions1502C MTDR User Manual1–17The reflection coefficient is a measure of the impedance change at a point in thecable. It is the rati

Operating Instructions1–181502C MTDR User Manualsimilar to the Vertical Compensation for Higher Impedance Cable procedure (seethe VERT SET REF section

Operating Instructions1502C MTDR User Manual1–19The 1502C can compute and display what impedance mismatch would cause areflection as high (or low) as

Operating Instructions1–201502C MTDR User ManualWhen pushed, the VIEW INPUT button displays the input at the front panelCABLE connector. When VIEW INP

Operating Instructions1502C MTDR User Manual1–21The VIEW STORE button, when pushed on, displays the waveform stored in thememory as a dotted line. If

Contacting TektronixPhone 1-800-833-9200*Address Tektronix, Inc.Department or name (if known)14200 SW Karl Braun DriveP.O. Box 500Beaverton, OR 97077U

Operating Instructions1–221502C MTDR User ManualOFFOFFONac 3.000 ftONFigure 1–19: Waveform Moved to Top Half of Display2. Push STORE to capture the wa

Operating Instructions1502C MTDR User Manual1–23ONac 3.000 ftONONONStoredWaveformVIEW STORECurrentWaveformVIEW INPUTDifferenceVIEW DIFFFigure 1–21: Cu

Operating Instructions1–241502C MTDR User ManualHORZ SET REF (D mode) allows you to offset the distance reading. Forexample, a lead-in cable to a swit

Operating Instructions1502C MTDR User Manual1–25OFFOFFOFFONac0.000 ftDFigure 1–24: Cursor Moved to End of Three-Foot Lead-in CableNOTE. Vp changes wil

Operating Instructions1–261502C MTDR User ManualVERT SET REF works similar to HORZ SET REF except that it sets a referencefor gain (pulse height) inst

Operating Instructions1502C MTDR User Manual1–27OFFOFFOFFONac 19.200 ftFigure 1–27: Waveform of Short 75 ohm Cable2. Adjust the noPOSITION control to

Operating Instructions1–281502C MTDR User ManualOFFOFFOFFONac 1.840 ftFigure 1–29: Cursor Moved to Desired PositionThe instrument is now set to measur

Operating Instructions1502C MTDR User Manual1–29Additional Features (Menu Selected)The 1502C will capture and store waveforms on an ongoing basis. Thi

Operating Instructions1–301502C MTDR User ManualONac 0.000 ftONCapturedchangesFigure 1–31: Waveform Showing Intermittent Changes8. To exit monitor mod

Operating Instructions1502C MTDR User Manual1–316. Repeatedly press MENU until the instrument returns to normal operation.CAUTION. This function is us

1502C MTDR User ManualiTable of ContentsGeneral Information vii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Install

Operating Instructions1–321502C MTDR User ManualOFFOFFOFFac 0.000 ftOFFFigure 1–33: A Captured Single Sweep8. To exit Single Sweep is: On, access the

1502C MTDR User Manual2–1Operator TutorialThis chapter will show, step by step, the features and uses of the 1502C.What is the Tektronix 1502C?The Tek

Operator Tutorial2–21502C MTDR User ManualGetting StartedLet’s start by inspecting a cable. For the next few examples, we will use the3-foot precision

Operator Tutorial1502C MTDR User Manual2–3ONac 0.000 ftOFFFigure 2–1: Display Showing 3-ft Cable in Start-Up Conditions3. The rising pulse on the left

Operator Tutorial2–41502C MTDR User ManualOFFOFFOFFONac 3.000 ftOpenFigure 2–3: Waveform with VERT SCALE Increased Showing an Open5. The noPOSITION co

Operator Tutorial1502C MTDR User Manual2–5The Waveform Up CloseIt helps to know what makes up a pulse. Here is the waveform anatomy using the3-foot te

Operator Tutorial2–61502C MTDR User ManualOFFOFFOFFONac –0.520 ftFigure 2–6: 3-foot Cable with Cursor at Incident Pulse5. Adjust the VERT SCALE contro

Operator Tutorial1502C MTDR User Manual2–7A Longer CableLonger cables might not fit in the display. Let’s demonstrate that with a longercable.Obtain a

Operator Tutorial2–81502C MTDR User ManualOFFOFFOFFONac 362.800 ftCursorCable Scrollingin this directionFigure 2–9: Scrolling Down the CableNOTE. When

Operator Tutorial1502C MTDR User Manual2–950 W impedance plus 9.5 W series resistance. You can check this by putting aknown reference on the end of th

Table of Contentsii1502C MTDR User ManualAppendix D: Application Note D–1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Pulse Echo Te

Operator Tutorial2–101502C MTDR User ManualOFFOFFOFFONac>=1 K W578.000 ftFigure 2–12: Ohms-at-Cursor Beyond Reflected Pulse9. Turn the noPOSITION c

Operator Tutorial1502C MTDR User Manual2–11NoiseOn a longer cable, “grass” might appear on the displayed waveform. This isprimarily caused by the cabl

Operator Tutorial2–121502C MTDR User ManualONac 40.000 ftOFFOFFOFFFigure 2–15: Noise Reduced5. Increase the NOISE FILTER setting to 128.NOTE. The high

Operator Tutorial1502C MTDR User Manual2–13Set Ref (Delta Mode)Horizontal Set Reference establishes the starting point at which the distancewindow beg

Operator Tutorial2–141502C MTDR User ManualOFFOFFOFFONac 3.000 ftreturn FILTER to desire setting . . .Figure 2–18: Cursor at 3.000 ft5. Turn the NOISE

Operator Tutorial1502C MTDR User Manual2–15This control is nearly the same as HORZ SET REF except it sets the verticalzero reference. It would be help

Operator Tutorial2–161502C MTDR User ManualOFFOFFOFFONac 0.000 ftreturn FILTER to desired setting ...Figure 2–21: VERT SCALE adjusted to Make Pulse Tw

Operator Tutorial1502C MTDR User Manual2–17VIEW INPUTThis push button allows you to view what is coming in the CABLE connector, orto eliminate it from

Operator Tutorial2–181502C MTDR User ManualThis function can be used to make the display less busy when viewing storedwaveforms.STORE and VIEW STORETh

Operator Tutorial1502C MTDR User Manual2–19OFFONac 0.000 ftONOFFFigure 2–25: Waveform with Cable Shorted7. Press VIEW STORE to view the stored wavefor

Table of Contents1502C MTDR User ManualiiiList of FiguresFigure 1–1: Rear Panel Voltage Selector, Fuse, AC Receptacle 1–2. . . . . Figure 1–2: Display

Operator Tutorial2–201502C MTDR User ManualVIEW DIFFPress VIEW DIFF. This adds a waveform in the lower portion of the display thatis the mathematical

Operator Tutorial1502C MTDR User Manual2–21Menu-Accessed FunctionsNOTE. If you get lost or confused while in a menu, repeatedly press the MENUbutton u

Operator Tutorial2–221502C MTDR User Manual13. Press MENU again to enter normal operations mode. Note that the VIEWSTORE and VIEW DIFF indicator block

Operator Tutorial1502C MTDR User Manual2–23You can probably see how this function is useful for monitoring lines forchanges over a period of time, or

Operator Tutorial2–241502C MTDR User ManualOFFOFFOFFONac 0.000 ftFigure 2–31: Display with Pulse Turned OffCAUTION. This function is used mostly for t

Operator Tutorial1502C MTDR User Manual2–2510. Press MENU repeatedly until the instrument returns to normal operation.The waveform on the display is t

Operator Tutorial2–261502C MTDR User Manual15. To exit Single Sweep, access the Acquisition Control Menu again, toggle theSingle Sweep is: line back t

Operator Tutorial1502C MTDR User Manual2–27Q8: What is resistance?A8: Resistance is the opposition to DC current flow, or DC voltage divided by DCcurr

Operator Tutorial2–281502C MTDR User Manual

1502C MTDR User Manual3–1Options and AccessoriesThe following options are available for the 1502C MTDR:Option 04: YT-1 Chart RecorderOption 04 instrum

Table of Contentsiv1502C MTDR User ManualFigure 1–32: Waveform Display with No Outgoing Pulses 1–30. . . . . . . . . Figure 1–33: A Captured Single Sw

Options and Accessories3–21502C MTDR User ManualTest Data Record OptionThis option provides the test data record obtained during the PerformanceVerifi

Options and Accessories1502C MTDR User Manual3–3Connector, BNC female to Dual Banana Plug 103-0090-00Connector, BNC male to Dual Binding Post 103-0035

Options and Accessories3–41502C MTDR User Manual

1502C MTDR User ManualA–1Appendix A: SpecificationsThe tables in this chapter list the characteristics and features that apply to thisinstrument after

Appendix A: SpecificationsA–21502C MTDR User ManualTable A–1: Electrical Characteristics (Cont.)Characteristic Supplemental InformationPerformance Req

Appendix A: Specifications1502C MTDR User ManualA–3Environmental CharacteristicsTable A–2: Environmental Characteristics Characteristic Performance Re

Appendix A: SpecificationsA–41502C MTDR User ManualCertifications and CompliancesCategory Standard or descriptionEC Declaration of Conformity –EMCMeet

Appendix A: Specifications1502C MTDR User ManualA–5Category Standard or descriptionPollution Degree A measure of the contaminates that could occur in

Appendix A: SpecificationsA–61502C MTDR User Manual

1502C MTDR User ManualB–1Appendix B: Operator Performance ChecksThis appendix contains performance checks for many of the functions of the1502C. They

Table of Contents1502C MTDR User ManualvFigure 2–33: Captured Single Sweep of Shorted Test Cable 2–25. . . . . . . . Figure B–1: Start-up Measurement

Appendix B: Operator Performance ChecksB–21502C MTDR User Manualoff, these checks must be repeated again when the instrument is powered onagain.Set th

Appendix B: Operator Performance Checks1502C MTDR User ManualB–3ONac 0.000 ftOFFOFFOFFFigure B–2: Measurement Display with 3-foot Cable3. Using the no

Appendix B: Operator Performance ChecksB–41502C MTDR User ManualONac 1.360 ftOFFOFFOFFFigure B–4: Cursor at End of 3-foot Cable, Vp Set to .306. Remov

Appendix B: Operator Performance Checks1502C MTDR User ManualB–5OFFOFFOFFONac –2.000 ftFigure B–6: Flat-Line Display at –2.000 ftThis last step has se

Appendix B: Operator Performance ChecksB–61502C MTDR User ManualOFFOFFOFFONac –2.000 ftWaveformFigure B–8: Waveform at the Bottom of the DisplayIf the

Appendix B: Operator Performance Checks1502C MTDR User ManualB–77. Press MENU again.8. Using the no POSITION control, select Noise Diagnostics.9. Pres

Appendix B: Operator Performance ChecksB–81502C MTDR User ManualIf the aberrations are out of specification, the ohms-at-cursor function might beless

Appendix B: Operator Performance Checks1502C MTDR User ManualB–9All the aberrations, except the one under the cursor (see Figure B–12), mustbe within

Appendix B: Operator Performance ChecksB–101502C MTDR User Manual3. Turn the VERT SCALE control clockwise until the leading edge of theincident pulse

Appendix B: Operator Performance Checks1502C MTDR User ManualB–11Jitter is the uncertainty in the timebase. Its main effect is that the waveformappear