HP 8147A Optical Time
Domain Reflectometer
User’s Guide
Notices
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Copyright 1996, 1997, 1998,
1999, 2001 by:
Hewlett-Packard GmbH
Herrenberger Str. 130
71034 Böblingen
Germany
Subject Matter
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for incidental or consequential
damages in connection with the
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of this material.
Printing History
New editions are complete revisions of the guide reflecting
alterations in the functionality of
the instrument. Updates are
occasionally made to the guide
between editions. The date on
the title page changes when an
updated guide is published. To
find out the current revision of
the guide, or to purchase an
updated guide, contact your
Hewlett-Packard representative.
Control Serial Number: First
Edition applies directly to all
instruments.
War rant y
This Hewlett-Packard instrument
product is warranted against
defects in material and workmanship for a period of one year
from date of shipment. During
the warranty period, HP will, at
its option, either repair or replace
products that prove to be defective.
For warranty service or repair,
this product must be returned to
a service facility designated by
HP. Buyer shall prepay shipping
charges to HP and HP shall pay
shipping charges to return the
product to Buyer. However,
Buyer shall pay all shipping
charges, duties, and taxes for
products returned to HP from
another country.
HP warrants that its software and
firmware designated by HP for
use with an instrument will execute its programming instructions when properly installed on
that instrument. HP does not
warrant that the operation of the
instrument, software, or
firmware will be uninterrupted
or error free.
Limitation of Warranty
The foregoing warranty shall not
apply to defects resulting from
improper or inadequate maintenance by Buyer, Buyer-supplied
software or interfacing, unauthorized modification or misuse,
operation outside of the environmental specifications for the
product, or improper site preparation or maintenance.
No other warranty is expressed
or implied. Hewlett-Packard specifically disclaims the implied
warranties of Merchantability
and Fitness for a Particular Purpose.
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The remedies provided herein
are Buyer’s sole and exclusive
remedies. Hewlett-Packard shall
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based on contract, tort, or any
other legal theory.
Assistance
Product maintenance agreements and other customer assistance agreements are available
for Hewlett-Packard products.
For any assistance contact your
nearest Hewlett-Packard Sales
and Service Office.
Certification
Hewlett-Packard Company certifies that this product met its published specifications at the time
of shipment from the factory.
Hewlett-Packard further certifies that its calibration measurements are traceable to the United
States National Institute of
Standards and Technology, NIST
(formerly the United States
National Bureau of Standards,
NBS) to the extent allowed by
the Institutes’s calibration facility, and to the calibration facilities of other International
Standards Organization members.
ISO 9001 Certification
Produced to ISO 9001 international quality system standard as
part of our objective of continually increasing customer satisfaction through improved
process control.
End-User License Agreement
1. The HP 8147A contains intellectual property, i. e. software
programs, that is licensed for the
end-user customer’s use (hereinafter “End-User”).
2. This is not a sale of such intellectual property.
3. The End-User shall not copy,
disassemble, reverse engineer, or
decompile the software program.
4. The Microsoft software programs are provided to the EndUser as is “without warranty of
any kind, either expressed or
implied, including, but not limited to, warranties of non-infringent, merchant-ability, and/or
fitness for a particular purpose.
The entire risk of the quality and
performance of the software program is with you.”
5. HP’s suppliers shall not be
held to any liability for any damages suffered or incurred by the
End-User (including, but not
limited to, general, special, consequential or incidental damages
including damages for loss of
business profits, business interruption, loss of business information and the like), arising
from or in conjunction with the
delivery, use or performance of
the software program.
Fifth Edition
E0401, April 2001
E4310-91011
First Edition E0895 August 1995
Second Edition E0595 May 1996
Third Edition E0397 Mar. 1997
Fourth Edition E0298 Feb. 1998
Fifth Edition E1098 Oct. 1998
E0796 July 1996
E0996 September1996
E0697 June 1997
E0997 September 1997
E1198, November 1998
E0599, May 1999
Hewlett-Packard GmbH
Herrenberger Str. 130
71034 Böblingen
Federal Republic of Germany
HP 8147A Optical Time Domain Reflectometer
User’s Guide
Safety Summary
The following general safety precautions must be observed during
all phases of operation, service, and repair of this instrument.
Failure to comply with these precautions or with specific warnings
elsewhere in this manual violates safety standards of design,
manufacture, and intended use of the instrument. Hewlett-Packard
Company assumes no liability for the customer’s failure to comply
with these requirements.
General This is a Safety Class 1 instrument (provided with terminal for protective earthing) and has been manufactured and tested according to international safety standards.
Operation – Before applying power Comply with the installation section. Additionally, the following shall be observed:
• Do not remove instrument covers when operating.
• Before the instrument is switched on, all protective earth
terminals, extension cords, auto-transformers and devices
connected to it should be connected to a protective earth via a
ground socket. Any interruption of the protective earth
grounding will cause a potential shock hazard that could result
in serious personal injury.
• Whenever it is likely that the protection has been impaired, the
instrument must be made inoperative and be secured against any
unintended operation.
• Make sure that only fuses with the required rated current and of
the specified type (normal blow, time delay, etc.) are used for
replacement. The use of repaired fuses and the short-circuiting
of fuseholders must be avoided.
• Adjustments described in the manual are performed with power
supplied to the instrument while protective covers are removed.
Be aware that energy at many points may, if contacted, result in
personal injury.
• Any adjustments, maintenance, and repair of the opened
instrument under voltage should be avoided as much as possible,
and when unavoidable, should be carried out only by a skilled
person who is aware of the hazard involved. Do not attempt
internal service or adjustment unless another person, capable of
rendering first aid and resuscitation is present. Do not replace
components with power cable connected.
4
Safety Summary
• Do not operate the instrument in the presence of flammable
gases or fumes. Operation of any electrical instrument in such an
environment constitutes a definite safety hazard.
• Do not install substitute parts or perform any unauthorized
modification to the instrument.
• Be aware that capacitors inside the instrument may still be
charged even if the instrument has been disconnected from its
source of supply.
Safety Symbols
The apparatus will be marked with this symbol when it is necessary
for the user to refer to the instruction manual in order to protect the
apparatus against damage.
Caution, risk of electric shock.
Frame or chassis terminal.
Protective conductor terminal.
Hazardous laser radiation.
Electromagnetic interference (EMI)
WAR N IN G The WARNING sign denotes a hazard. It calls attention to a procedure,
practice or the like, which, if not correctly performed or adhered to,
could result in injury or loss of life. Do not proceed beyond a
WARNING sign until the indicated conditions are fully understood and
met.
CAUTION The CAUTION sign denotes a hazard. It calls attention to an operating
procedure, practice or the like, which, if not correctly performed or adhered
to, could result in damage to or destruction of part or all of the equipment.
Do not proceed beyond a CAUTION sign until the indicated conditions are
fully understood and met.
5
Safety Summary
Initial Safety Information for Laser Source
The specifications for the modules are as follows:
E4311A E4312A E4313A
Laser Type FP-Laser
InGaAsP
Laser Class
According to IEC 825 (Europe) 3A 3A 3A
According to 21 CFR 1040.10
(Canada, Japan, USA)
Output Power (Pulse Max) 7.5 mW 7.5 mW 7.5 mW
Pulse Duration (Max) 10 µs10 µs10 µs
Pulse Energy (Max) 75 nWs 75 nWs 75 nWs
Output Power (CW) 0.5 mW 0.5 mW 0.5 mW
Beam Waist Diameter 9 µm9 µm9 µm
Numerical Aperture 0.1 0.1 0.1
Wavel ength 1310 ±15nm 1550 ±15nm 1310/1550
E4314A E4315A E4316A
Laser Type FP-Laser
InGaAsP
Laser Class
According to IEC 825 (Europe) 3A 3A 3A
According to 21 CFR 1040.10
(Canada, Japan, USA)
Output Power (Pulse Max) 25 mW 25 mW 25 mW
Pulse Duration (Max) 10 µs10 µs10 µs
Pulse Energy (Max) 250 nWs 250 nWs 250 nWs
Output Power (CW) 1 mW 1 mW 1 mW
Beam Waist Diameter 9 µm9 µm9 µm
Numerical Aperture 0.1 0.1 0.1
Wavel ength 1310 ±15nm 1550 ±15nm 1310/1550
FP-Laser
InGaAsP
111
FP-Laser
InGaAsP
111
FP-Laser
InGaAsP
±15nm
FP-Laser
InGaAsP
±15nm
6
Safety Summary
E4317A E4318A E4319A
Laser Type FP-Laser
InGaAsP
Laser Class
According to IEC 825 (Europe) 3A 3A 3A
According to 21 CFR 1040.10
(Canada, Japan, USA)
Output Power (Pulse Max) 50 mW 50 mW 50 mW
Pulse Duration (Max) 20 µs20 µs20 µs
Pulse Energy (Max) 1 mWs 1 mWs 1 mWs
Output Power (CW) 1 mW 1 mW 1 mW
Beam Waist Diameter 9 µm9 µm9 µm
Numerical Aperture 0.1 0.1 0.1
Wavel ength 1310 ±15nm 1550 ±15nm 1310/1550
E4321A E4324A
Laser Type FP-Laser
InGaAsP
Laser Class
According to IEC 825 (Europe) 3A 3A
According to 21 CFR 1040.10
(Canada, Japan, USA)
Output Power (Pulse Max) 50 mW 60 mW
Pulse Duration (Max) 20 µs20 µs
Pulse Energy (Max) 1 mWs 1 mWs
Output Power (CW) 1 mW 1 mW
Beam Waist Diameter 9 µm9 µm
Numerical Aperture 0.1 0.1
Wavel ength 1625 ±20nm 1310/1550
FP-Laser
InGaAsP
111
FP-Laser
InGaAsP
11
±15nm
FP-Laser
InGaAsP
±15nm
7
NOTE
Safety Summary
The laser safety warning labels are fixed on the front panel of the instrument.
A sheet of laser safety warning labels is included with the laser module.
Yo u must stick the labels in the local language onto the outside of the
instrument, in a position where they are clearly visible to anyone using
the instrument.
The recommended position for the laser safety warning label is to
the Laser Active LED on the front of the instrument as shown by
the arrow in the diagram below.
Yo u must return instruments with malfunctioning laser modules to
a HP Service Center for repair and calibration, or have the repair
and calibration performed on-site by HP personnel.
The laser module has built in safety circuitry that disables the
optical output in the case of a fault condition.
8
Safety Summary
WARN I NG Use of controls or adjustments or performance of procedures other
than those specified for the laser source may result in hazardous
radiation exposure.
WARN I NG Refer Servicing only to qualified and authorized personnel.
WARN I NG Do not enable the laser when there is no fiber attached to the optical
output connector.
The optical output connector is at the bottom right corner of the
instrument’s front panel.
The laser is enabled by pressing R
UN/STOP. The laser is enabled when
the green LED on the front panel of the laser module is lit.
WARN I NG Under no circumstances look into the end of an optical cable attached
to the optical output when the device is operational.
The laser radiation is not visible to the human eye, but it can seriously
damage your eyesight.
There is a safety circuit which monitors the average laser power
output, and the power output of each laser pulse. If either the
9
Safety Summary
average or the pulse power is greater than the limit for the module,
the laser will be disabled.
OTDR Year 2000 Compliance
All new OTDRs are Year 2000 compliant. However, earlier models
(manufactured before July 1998, and with serial numbers
DE35501422 and lower) may not yet be compliant.
There is a risk that at the millennium such models will be reset to
01 April, 1980.
You do not need to return any instruments to Hewlett-Packard to
make them Year 2000 Compliant. Simply follow the instructions on
our Webpages.
You can see our Webpages at
Select
Support, then Year 2000 Compliance. Select
HP8147/E4310A Year 2000 Compliance for instructions
as to how you can update your OTDR.
If you have any problems updating your OTDR, please contact your
nearest support center, or your Hewlett-Packard representative.
www.hp.com/go/lightwave.
Bellcore Certification of Excellence
Hewlett-Packard is officially designated Bellcore Certification
Eligible, and is awarded Bellcore’s Certification of Excellence for
its OTDR Data Format.
10
In This Book
The Structure of this Manual
This manual is divided into four parts:
• An introduction to the OTDR’s features.
• A sample session showing a typical measurement, in chapters 2
and 3.
• A description of the capabilities of the OTDR’s macro recording,
in chapter 4.
• Additional information not required for routine day-to-day use
in the appendix
Conventions used in this Manual
Small capitals are used to indicate front panel keys, softkeys and
menu items, e. g. S
ETTINGS.
11
Safety Summary
12
Table of Contents
OTDR Year 2000 Compliance 10
Bellcore Certification of Excellence 10
1 Getting Started
1.1 How the OTDR Works 27
Events 27
1.2 Expert and Easy Mode 28
1.3 What You Can Measure with the OTDR 28
1.4 The Front Panel 29
1.5 The Trace Screen 29
1.6 The Keys 32
The Hardkeys 32
The Softkeys 35
Modify knob 36
1.7 Function Overview 36
1.8 Getting Help 41
2 Elementary Sample Sessions
2.1 How to Connect the Fiber 45
2.2 How To Set Up the Parameters 45
How to Change the Refractive Index 45
How to Adjust the Refractive Index for a fiber of known length 47
2.3 How to Make an Automatic Measurement 47
13
Table of Contents
2.4 How to Scan for Events 49
How to Change the Event Thresholds 49
How to Activate the Scan Trace Function 50
2.5 How to Use the Event Table 51
How to Display the Event Table 51
How to Select an Event in the Table 52
How to Close the Event Table 52
2.6 How to Use Landmarks 53
How to Add a Landmark 53
How to Add a Landmark to a Trace 53
How to Add a Landmark to the Event Table 55
How to Modify the Name of an Existing Landmark 55
How to Delete Landmarks 55
Deleting All Landmarks 56
2.7 How to Change the Vertical Offset 56
How to Restore the Automatic Offset 57
2.8 How to Print the Measurement 57
How to Print the Current Measurement 57
How to Print All Measurements 58
How to Print to an External Printer 58
2.9 How to Save the Measurement 59
How to Save to a User-Defined Name 60
2.10 How to Run a Manual Measurement 60
How to Change the Measurement Span 60
How to Change the Optimization Mode 61
How to Run the Measurement 61
2.11 How to Display more than one trace 62
How to change the style of the current trace 64
How to set 2 traces to the same vertical offset 64
14
Table of Contents
How to Close a Trace 64
2.12 How to Set Labels for Trace Information 65
How to view the Current Trace Information. 65
How to Enter new Trace Information 66
How to Change the Trace Info Labels 66
2.13 How to Set the Time and Date 67
How to Change the Date 68
How to Change the Time. 68
How to Confirm the new Time and Date 68
3 Further Sample Sessions
3.1 How to Add an Event 71
How to Add a Reflective Event 71
How to Add a Non-Reflective Event 76
3.2 How to Measure Loss and Attenuation 77
How to Measure 2-Point Loss 77
How to Measure 2-Point Attenuation 78
How to Measure LSA Attenuation 78
How to Measure Optical Return Loss 79
3.3 How to Measure the Total Loss of a Fiber 79
3.4 How to Take a Two-Way Measurement 82
How to synchronize traces before Averaging 83
3.5 How to Subtract One Measurement from Another 85
How to Synchronize Traces before Subtracting 85
3.6 How to Use Stored Settings 86
How to Store Parameter Settings 87
15
Table of Contents
How to Recall Stored Settings 87
How to Delete Stored Settings 87
3.7 How to Connect to the OTDR via LAN 88
How to connect using Windows NT Explorer 90
4 Macro Programming
4.1 Recording Macros 93
4.2 Activating Macros 94
4.3 Editing Macros 95
4.4 Macro Commands 96
Overview 96
Commands For Setting Parameters 98
Commands For Running Measurements 102
Commands For Documenting Measurements 103
Commands For Changing the Display 105
Commands for Comments and Flow Control 107
Commands for Analyzing Measurements 111
Additional commands 112
4.5 Example 112
A Installation and Maintenance
A.1 Safety Considerations 117
A.2 Initial Inspection 117
16
Table of Contents
A.3 AC Line Power Supply Requirements 118
Line Power Cable 118
Replacing the Battery 120
A.4 DC Power Supply Requirements (Option 001) 121
A.5 Operating and Storage Environment 122
Temperature 122
Humidity 122
Altitude 122
Instrument Positioning and Cooling 123
A.6 Switching on the OTDR 123
A.7 Optical Output 124
A.8 Parallel Interface 124
A.9 Serial Interfaces 124
A.10 Keyboard, Mouse, and VGA Display Interfaces 125
A.11 HP-IB Interface (Option 004) 125
Connector 126
HP-IB Logic Levels 127
A.12 LAN Interface (Option 005) 127
Connector 128
Available HP Cables 128
A.13 Claims and Repackaging 129
Return Shipments to HP 129
A.14 Installing or Changing the Paper Roll 130
How to Remove the Paper Roll 130
How to Insert the New Paper Roll 131
How to Purchase New Paper Rolls 132
A.15 Installing New Software 132
17
Table of Contents
B Accessories
B.1 Instrument and Options 137
B.2 HP-IB Cables and Adapters 139
B.3 Connector Interfaces and Other Accessories 140
C Specifications
C.1 Definition of Terms 145
C.2 Specifications 152
Horizontal Parameters 152
Vertical Parameters 153
CW Mode 153
Pulsewidth 153
Output connector 153
Automatic setup and analysis 154
Documentation 154
Scan Trace 154
Display 155
Interfaces 155
General 155
Environmental 156
Power 156
C.3 Module Specifications 157
Optical Performance 157
Distance Accuracy 158
Loss/Reflectance Accuracy 158
18
Table of Contents
C.4 Other Specifications 159
C.5 Declaration of Conformity 160
D Single-Mode Module Performance Tests
D.1 General 165
Equipment Required 165
Test Record 165
Test Failure 166
Instrument Specification 166
Performance Tests 166
D.2 Test I. Dynamic Range 167
D.3 Test II. Event Deadzone 173
D.4 Test III. Attenuation Deadzone 179
D.5 Test IV. Distance Accuracy 184
D.6 Test V. Loss Accuracy 190
D.7 Test VI. Reflectance Accuracy 194
D.8 Performance Test Form Sheets 200
E Cleaning Procedures
E.1 Cleaning Materials 215
E.2 Cleaning Fiber/Front-Panel Connectors 215
E.3 Cleaning Connector Interfaces 216
19
Table of Contents
E.4 Cleaning Connector Bushings 216
E.5 Cleaning Detector Windows 217
E.6 Cleaning Lens Adapters 217
E.7 Cleaning Detector Lens Interfaces 217
F Error Codes
F.1 Display Error Messages 221
F.2 Remote Error Messages 228
G Overview
G.1 Elementary Sample Sessions 233
20
List of Figures
Figure 1-1 Reflective (Left) and Non-Reflective (Right) Events............................... 27
Figure 1-2 The Front Panel......................................................................................... 30
Figure 1-3 The Trace Screen ...................................................................................... 31
Figure 1-4 The Zoom Keys......................................................................................... 32
Figure 1-5 The Function Keys.................................................................................... 33
Figure 1-6 The Location of the Softkeys .................................................................... 35
Figure 1-7 The Modify Knob...................................................................................... 36
Figure 1-8 Softkey functions ...................................................................................... 40
Figure 1-9 The OTDR’s Help Display ....................................................................... 41
Figure 2-1 Overview screen........................................................................................ 46
Figure 2-2 The Measurement Trace............................................................................ 48
Figure 2-3 Modify Threshold value............................................................................ 50
Figure 2-4 The Event Table........................................................................................ 51
Figure 2-5 Enter a Landmark...................................................................................... 54
Figure 2-6 Setting the Range ...................................................................................... 61
Figure 2-7 The Trace of the Manual Measurement .................................................... 62
Figure 2-8 Two traces on the same picture................................................................. 63
Figure 2-9 Current Trace Information ........................................................................ 66
Figure 2-10 Set the Time and Date............................................................................. 67
Figure 3-1 Add Reflective Event: Level-Markers ...................................................... 72
Figure 3-2 Add Reflective Event: Level-Markers set................................................. 73
Figure 3-3 Add Non-Reflective Event: Level-Markers.............................................. 74
Figure 3-4 Add Non-Reflective Event: Level-Markers set ........................................ 76
Figure 3-5 Measure Total Loss: Position Marker B ................................................... 80
Figure 3-6 Measure Total Loss: Position Marker A ................................................... 81
Figure 3-7 Two-Way Measurement: traces ................................................................ 83
Figure 3-8 Two-Way Measurement: Event Table ...................................................... 84
Figure 3-9 Subtract Measurements: result.................................................................. 86
Figure 3-10 LAN Settings window............................................................................. 89
Figure A-1 Line Power Cables – Plug Identification ................................................. 118
Figure A-2 Rear Panel Markings................................................................................ 120
Figure A-3 Correct Positioning of the OTDR ............................................................ 123
Figure A-4 The HP-IB Connector .............................................................................. 126
Figure A-5 LAN Connector........................................................................................ 128
Figure A-6 The Printer Module Turned Upside Down............................................... 130
21
List of Figures
Figure C-1 Attenuation deadzone definition .............................................................. 145
Figure C-2 Near-end backscatter level for 3 different near-end reflectances............. 146
Figure C-3 Elements of the distance accuracy ........................................................... 147
Figure C-4 Determining the location of a reflective event......................................... 148
Figure C-5 Definition of event deadzone ................................................................... 150
Figure C-6 Loss error samples for 1 dB loss (arbitrary units).................................... 151
Figure D-1 Dynamic Range Test Setup...................................................................... 167
Figure D-2 Dynamic Range Test: Full Trace View ................................................... 170
Figure D-3 Dynamic Range Test: Position Marker at End of Frontreflection ........... 172
Figure D-4 Event Deadzone Test Setup ..................................................................... 174
Figure D-5 Event Deadzone Test: Position Marker A ............................................... 176
Figure D-6 Event Deadzone Test: Position Marker B................................................ 178
Figure D-7 Attenuation Deadzone Test: Position Marker C ...................................... 181
Figure D-8 Attenuation Deadzone Test: Position Marker B at End of Reflection..... 182
Figure D-9 Attenuation Deadzone Test: Position Marker A at Start of Reflection ... 183
Figure D-10 Distance Accuracy Test Setup ............................................................... 184
Figure D-11 Distance Accuracy Test: Position Markers............................................ 187
Figure D-12 Distance Accuracy Test: Around Marker View..................................... 188
Figure D-13 Loss Measurement Test Setup ............................................................... 190
Figure D-14 Loss Accuracy Test: Position Marker B ................................................ 192
Figure D-15 Loss Accuracy Test: Reference Measurement Setup............................. 193
Figure D-16 Reflection Measurement Test Setup ...................................................... 194
Figure D-17 Reflectance Accuracy Test: Position Markers....................................... 197
Figure D-18 Reflectance Accuracy Test: Position Auxiliary Markers....................... 199
Figure G-1 Configure the instrument ......................................................................... 234
Figure G-2 View a Trace............................................................................................ 235
Figure G-3 Use the printer.......................................................................................... 236
Figure G-4 Add/Delete Landmarks ............................................................................ 237
Figure G-5 Read from/Write to a Floppy Disk........................................................... 238
22
List of Tables
Table 1-1 Keyboard emulation of hardkeys ............................................................... 34
Table D-1 Module dependent settings for Dynamic Range Test................................ 169
23
List of Tables
24
1
1 Getting Started
Getting Started
This chapter introduces the features of the HP 8147A Optical Time
Domain Reflectometer (OTDR). Here you will find a quick
description of the instrument, how to get online help, and a sample
session to help you familiarize yourself with the operation of the
instrument.
26
Getting Started
How the OTDR Works
1.1 How the OTDR Works
The OTDR repeatedly outputs an optical pulse into the connected
fiber and measures the reflections from this pulse. The trace
displayed on the screen is a graph of this reflected power
(backscatter) as a function of the distance along the fiber.
Events
Events are changes in the fiber causing the trace to deviate from a
straight line. Events can be Reflective or Non-Reflective.
Reflective Events occur when some of the pulse energy is reflected,
for example at a connector. Reflective Events produce a spike in the
trace (you see a steep rise and fall in the graph: see the first diagram
below).
Non-Reflective Events occur at parts of the fiber where there is
some loss but no light is reflected. Non-Reflective Events produce a
dip on the trace (see the second diagram below).
Figure 1-1 Reflective (Left) and Non-Reflective (Right) Events
The OTDR calculates the distance of such an “event” in the fiber
from the time it takes the reflected signal to return. The further
27
Getting Started
Expert and Easy Mode
away an event is, the longer it takes for its reflection to return to the
OTDR.
By examining the trace of the reflected signal, the parameters of the
fiber and the connectors, splices and so on can be determined.
1.2 Expert and Easy Mode
The OTDR works in one of two possible modes:
• In expert mode you can change all parameter settings and do
complex analysis on the results. You can also store settings and
record macros to prepare the instrument for an inexperienced
user.
• In easy mode the inexperienced user can recall stored settings,
activate macros, and run measurements without concerning
himself with parameters and other details.
You can change between the two modes using the OTDR’s
softkeys.
1.3 What You Can Measure with the OTDR
The OTDR displays the relative power of the returned signal
against distance. With this information important characteristics of
a link are determined:
• the location (distance) of events on the link, the end of the link
or a break,
• the attenuation of the fiber in the link,
• the loss of an individual event (for example a splice) or the total
end-to-end loss of the link,
28
Getting Started
The Front Panel
• the size of the reflection (or return loss) of an event, such as a
connector.
A fully automatic function is available for these measurements. The
OTDR sets itself up to achieve the best results.
In addition to these features the OTDR is able to compare
measurement results:
• You can load up to four traces and display them on the OTDR’s
screen.
• You can load two traces and subtract them. In so doing, you can
see any differences in the two measurements as a graph.
• You can also do measurements from both sides of the fiber and
average them (two-way measurement). This gives the most
accurate splice measurement, in the form of a graph and an event
table.
1.4 The Front Panel
Figure 1-2 shows the front panel of the HP 8147A.
The front panel consists of the following elements:
1.5 The Trace Screen
The trace screen is the main screen of the OTDR:
• When you have taken a measurement, the graph of the reflected
power is displayed as a function of distance. This graph is called
the trace.
29
Getting Started
The Trace Screen
Figure 1-2 The Front Panel
1 softkeys 2 modify knob
10
1
5 3
8147
OPTICAL TIME DOMAIN REFLECTOMETER
ZOOM MODIFY
Trace/
Save
Event
Print
Auto
9
7
Next
Marker
Around
Marker
Full
Trace
Run/
Stop
Press knob to
select/enter
2
8
6
Laser Active
4
3 help key 4 optical output
5 contrast-control keys 6 Laser Active LED
7 zoom keys 8 floppy disk drive
9 function keys 10 printer slot
• Below the trace, the event bar shows you the position of the
detected events: non-reflective events such as splices, reflective
events such as connectors, as well as any defined landmarks.
• The markers are your means of marking and analyzing single
events or parts of the trace. In the marker-information window,
you see information such as the distance, attenuation, and loss at
or between the markers.
• No matter when you zoom to a point of interest on the trace, you
do not lose orientation, as there is an overview display in the fulltrace window. You always know where you are. The full-trace
window is shown in the bottom left-hand corner of the display.
30
In addition to the trace
screen shown in
Figure 1-3, you have
the event-table screen
and the return-losschart screen. These
are used during
measurements and
analyzing. See the
online-documentation
for information about
these screens.
Getting Started
The Trace Screen
Figure 1-3 The Trace Screen
In the title bar you can see the name of the measurement file
(UNNAMED.SOR if you have not already saved the
measurement).
• The most important measurement parameters (such as
measurement range, pulsewidth, wavelength) are always shown
in the parameter window.
• On the right-hand side of the screen you can see the list of
functions for the softkeys.
31
Getting Started
The Keys
1.6 The Keys
There are three types of keys on the front of the OTDR: hardkeys,
softkeys, and the Modify knob.
The Hardkeys
The hardkeys are the keys with a fixed function. The function is
written on the key.
ZOOM
Next
Marker
Around
Marker
Figure 1-4 The Zoom Keys
The zoom keys are your means of zooming in and out on the
displayed trace. Using the zoom keys, you can shrink or stretch the
trace in either direction.
You can also zoom around or between the markers on the trace:
• The N
A, B, C, and AB.
• Pressing the A
around the current marker or between the markers A and B. The
marker (or the marked part) stays in the center of the grid, even
when you change its position on the trace using the knob.
32
Full
Trace
EXT M ARKER hardkey lets you toggle between the markers
ROUND MARKER hardkey zooms in the trace
Getting Started
The Keys
• If at any stage during zooming you wish to return to the whole
trace, this can be done by simply pressing the F
ULL TRACE
hardkey.
Save Trace/
Print
Event
Auto
Figure 1-5 The Function Keys
The function keys let you initiate an action with a single stroke of a
key:
• Pressing the S
• The T
RACE/EVENT hardkey lets you toggle between the trace
and the event table screen.
• Pressing the P
• Pressing the A
mode, for automatic detection of the best settings.
• Pressing the R
• Holding the R
between Average mode and Refresh mode.
Hardkeys: Keyboard equivalents
If you have a keyboard attached to your OTDR, you can emulate
the hardkeys from the keyboard as following:
Run/
Stop
AVE hardkey saves the current measurement.
RINT hardkey prints the current measurement.
UTO hardkey activates an Auto measurement
UN/STOP key starts or stops a measurement.
UN/STOP key for at least 3 seconds toggles
33
Getting Started
The Keys
Hardkey Keyboard equivalent
HELP (?) <f1>
N
EXT MARKER <f2>
A
ROUND MARKER <f3>
F
ULL TRACE <f4>
S
AVE <f5>
T
RACE/EVENT <f6>
P
RINT <f7>
A
UTO <f8>
R
UN/STOP <f9>
Table 1-1 Keyboard emulation of hardkeys
34
Getting Started
The Keys
The Softkeys
The softkeys are to be found at the right-hand side of the screen.
They have different functions in different situations. The actual
function is always written on the screen beside the key. A blank
softkey means that there is no action applied at this level.
Figure 1-6 The Location of the Softkeys
Softkeys: Keyboard equivalents
If you have a keyboard attached to your OTDR, you can emulate
the softkeys from the keyboard by holding down the <A
and pressing one of the numbers 1 to 6.
So <A
LT>1 emulates the top softkey, <ALT>2 the second softkey,
and so on.
35
– +
?
LT> key
Getting Started
Function Overview
Modify knob
MODIFY
Figure 1-7 The Modify Knob
Turning the Knob
Turning the Modify knob is like using the cursor keys on a
computer keyboard. You use the knob to select an entry in a menu
or in a list, or to change the value of a parameter.
You also turn the knob to move the markers on the trace.
Pressing the Knob
Pressing the Modify knob is like using the enter key on a computer
keyboard. You press the knob to confirm the selection or the
parameter value.
1.7 Function Overview
Figure 1-8 gives you an overview of the menus and functions you
can reach using the softkeys.
36
Getting Started
Function Overview
You see the name the 6 softkeys at the right of the OTDR screen.
You can press the bottom softkey to toggle between the different
softkey layers;
Layer 1 (
1/3) allows you to press the other softkeys to access the
menu options listed in Figure 1-8.
You use the Modify knob to select a menu option. Turn the knob to
move to move to an option; press the knob to select the highlighted
option.
Layer 2 (
(Width of Range), PW
and A
Layer 3 (
2/3) allows you to alter the START (Start of Range), SPAN
IDTH (Pulsewidth), WLENGTH (Wavelength)
VGTIME (Averaging Time) in the parameter window.
3/3) allows you to view an OVERVIEW of the parameter
setup, allowing you to alter more than one parameter at a time. You
may also alter the O
and V.O
FFS. (Vertical Offset), or use the fifth softkey to toggle
PTIMIZE mode, IOR (global refractive index),
between the selected traces.
37
Getting Started
Function Overview
The fifth softkey in layer 3 allows you to switch between different
traces. If there is a current trace, its name will appear as the softkey
38
Getting Started
Function Overview
label. If there is no current trace, the label is blank, and this feature
is unavailable.
39
Getting Started
Function Overview
Settings Analysis File View Config. 1/3
Optimize Mode
Refractive Index Delete Event Open Trace Event Table Language
Scatter Coefficient
Measurement
Mode
Event Thresholds Landmark Trace Infos
Front Connector
Check
Recall Settings
Store Settings
Copy Settings
Delete Settings Scan Trace Delete Directory Clear Hor. Offset
Add/Modify
Event
Add/Modify
Event Comment
Delete Event
Comment
Analyze
Insertion Loss
Analyze
Reflectance
Two-Way
Measurement
Subtract
Measurement
Lock Event
Tab le
2-Pt. Loss Print Trace Macro-Recorder
2-Pt. Attenuation Print Directory
LSA-
Attenuation
Optical Return
Loss
Close All Trace
Close Trace
Delete Trace Event Bar Length Unit
Save Trace Preferences Storage Device
Save Trace As Current Trace Print Device
Copy Trace Vertical Offset
Create Directory
Format Floppy
Cancel Print RS-232 Settings
Modify Print
Layout
Return Loss
Chart
Events before
Offset
Set Hor. Offset
to A
Enable
EasyMode
Date / Time
Trace Info.
Labels Header
Setup External
Printer
Power-On
Setting
Assign
Settings/Macros
Unassign
Settings/Macros
Select Remote
Interface
HP-IB Settings
LAN Settings
Perform Selftest
About
StartPos Span PWidth WLength Avg Time 2/3
Overview Optimize IOR V.Offs. <filename>3/3
Figure 1-8 Softkey functions
40
Getting Started
Getting Help
1.8 Getting Help
To get help on the OTDR you press the help key [?] to activate the
online documentation. The key can be found in the lower righthand corner of the display, below the softkeys.
Pressing [?] once opens up a page of the online documentation (a
topic) that shows information about the current screen. From there
you can jump to related topics.
Figure 1-9 The OTDR’s Help Display
To leave the online documentation and return to the measurement,
you press the E
On the left-hand side of the display, you can see the navigator
window. The navigator is your means of switching between the
41
XIT softkey.
Getting Started
Getting Help
topics like the chapters of a book. The actual topic is always
highlighted.
To select the Navigator, press the N
AV./TOP softkey.
42
2
2 Elementary Sample
Sessions
Elementary Sample
Sessions
This chapter contains a number of sample sessions of step-by-step
guides, showing how you use common features of the OTDR.
In these sample sessions we use:
• An OTDR HP 8147 in expert mode with an optical module HP
E4316A (1310/1550 nm, single-mode).
• A length of fiber of about 40 km, terminated at one end with a
Diamond HMS-10/HP connector and unterminated at the other
end. The fiber has a refractive index of 1.462, and is to be used
at a wavelength of 1310 nm.
• A connector interface to match the connector on the fiber being
used.
You can see some further Sample Sessions in the next chapter.
44
Elementary Sample Sessions
How to Connect the Fiber
2.1 How to Connect the Fiber
Connecting the fiber to the OTDR is very easy. You do not need any
tools. You connect the fiber as follows.
1 Clean the connectors.
2 Attach the required optical connector interface to the front of the
OTDR.
3 Connect the fiber.
2.2 How To Set Up the Parameters
This section describes the initial setting up of the OTDR and shows
how to change some parameters. First of all:
1 Switch on the OTDR.
The system is booted, and then performs a self-test.
Afterwards the trace screen appears. You can see the current
parameter settings in the parameter window.
How to Change the Refractive Index
To get the most accurate distance measurements, you have to enter
the correct refractive index:
1 Press the bottom softkey until you see screen
2 Press the O
45
VERVIEW softkey.
3/3.
Elementary Sample Sessions
How To Set Up the Parameters
You see a screen showing values that you can set (Figure 2-1).
Figure 2-1 Overview screen
3 Turn the Modify knob to move to the
4 When the Refr. Ind. box is highlighted, press the Modify knob.
You can now turn the Modify knob to increase or decrease the
displayed Refractive Index.
5 Turn the Modify knob to change the value, for example to
1.46200.
6 Press the Modify knob to accept this value.
7 If you want to change any other trace settings, move to the
appropriate box and select a new value.
8 Press the C
You can see the new Refractive Index in the table beneath the
trace after
46
Refr. Ind. box.
ONFIRM softkey to set the new value(s).
n:.
Elementary Sample Sessions
How to Make an Automatic Measurement
How to Adjust the Refractive Index for a fiber of known length
If you know the length of a fiber, you may wish to reset the
Refractive Index to equal that at the fiber end:
After you have made the trace, follow the following steps:
1 Move the current marker to the end of the fiber.
2 Press the bottom softkey until you see screen 3/3.
3 Press the IOR softkey.
4 Turn the Modify knob to adjust the refractive index.
The Refractive Index for the whole fiber is now set to the value
you see in the parameter window below the Trace.
NO T E You can also alter the Refractive Index for the whole fiber by selecting
{S
ETTINGS}REFRACTIVE INDEX - TOTAL from screen {1/3}.
To set the Refractive Index just at the current marker, select
{SETTINGS}REFRACTIVE INDEX - PARTIAL.
2.3 How to Make an Automatic Measurement
This section describes how to run an automatic measurement.
NOT E If you are taking a measurement at 1625 nm (E4321A module only),
you must make sure that the correct scatter coefficient is selected.
An incorrect scatter coefficient will result in incorrect reflectance
values.
To let the OTDR set up itself for the measurement:
47
Elementary Sample Sessions
How to Make an Automatic Measurement
1 Connect a fiber.
See “How to Connect the Fiber” on page 45.
2 Press the A
UTO hardkey twice to activate the Auto standard
optimization.
You see the optimization mode in the parameter window.
3 Press the R
UN/STOP hardkey.
The Laser Active sign lights up. After a short initializing phase,
the OTDR displays the first result.
4 Wait for the trace to become free of noise (takes some seconds).
Once sufficient information has been obtained, the OTDR
automatically analyzes the trace and creates an event table.
Figure 2-2 The Measurement Trace
48
Elementary Sample Sessions
How to Scan for Events
5 Press the RUN/STOP hardkey.
The Laser Active sign goes off. No more samples are being
taken.
2.4 How to Scan for Events
During a measurement, the OTDR automatically scans the trace for
Non-Reflective Events (such as fusion splices) and Reflective
Events (such as connectors). The current Event Thresholds are
used.
You can change these thresholds and re-scan the trace. You can also
use the scan trace function to scan traces copied to your OTDR
which do not yet have an Event Table (for details of the Event
Table, see “How to Use the Event Table” on page 51).
How to Change the Event Thresholds
1 Press the bottom softkey until you see screen 1/3.
2 Press the {S
the {S
You see a submenu which lets you select N
E
VENTS, REFLECTIVE EVENTS, or FIBER END.
ETTINGS} softkey. Select EVENT THRESHOLDS from
ETTINGS} menu.
ON-REFLECTIVE
3 Select the Event type for which you want to set the threshold.
49
Elementary Sample Sessions
How to Scan for Events
You see a window displaying the current Threshold value
(Figure 2-3).
Figure 2-3 Modify Threshold value
4 Turn the Modify knob to select a new Threshold value.
5 Press the Modify knob to enter the new value.
6 Repeat this process to set other thresholds as required.
How to Activate the Scan Trace Function
WAR N I N G Activating the Scan Trace function will delete all Events that you have
added manually.
7 Press the {A
{A
NALYSIS} menu.
After the Scan Trace had been performed, you see the Event Bar
below the trace. You can see more detailed information in the Event
Table (see below).
50
NALYSIS} softkey. Select SCAN TRACE from the
Elementary Sample Sessions
How to Use the Event Table
2.5 How to Use the Event Table
You can also add events
manually. See the online
documentation for further
information.
The OTDR automatically scans the trace for non-reflective events
(for example splices) and reflective events (for example
connectors). These events are shown on the event bar and in the
event table. This section describes how to read the event table.
How to Display the Event Table
To display the event table on the screen:
1 Press the T
You see the Event Table (Figure 2-4).
RACE/EVENT hardkey.
Figure 2-4 The Event Table
51
Elementary Sample Sessions
How to Use the Event Table
NO T E You can also view the Event Table by selecting EVENT TABLE from the
{VIEW} menu.
For each event in the table, you can see the type of the event and its
location. Furthermore you see the following measurement results:
• The reflectance of the event.
• The insertion loss of the event.
• The attenuation between this event and the next one.
• The cumulative loss, that is the sum of the splice, reflectance,
and attenuation loss up to the point of the current event. It
includes the loss of the current event.
In the windows at the bottom of the table (full-trace window,
around-marker window) you see the position of the selected event
on the trace.
How to Select an Event in the Table
2 Turn the Modify knob to move the highlighted bar in the Event
Tabl e.
Marker C is always at the selected event. You can see the zoom
around marker C in the Around Marker window at the bottom
left of the OTDR screen.
How to Close the Event Table
3 Press the TRACE/EVENT hardkey again.
NO T E You can also close the Event Table by selecting TRACE from the {VIEW}
menu.
You now see the trace with marker C at the last selected Event.
52
Elementary Sample Sessions
How to Use Landmarks
2.6 How to Use Landmarks
How to Add a Landmark
You can add landmarks to the trace or the event table. You use
landmarks to identify the physical location of an event.
How to Add a Landmark to a Trace
1 Move the active marker to the point where you want to add the
landmark.
You see the physical location (in km) at the top of the marker.
2 Press the bottom softkey until you see screen
3 Press the {A
M
ODIFY from the {ANALYSIS} menu.
NALYSIS} softkey. Select LANDMARK – ADD/
1/3.
53
Elementary Sample Sessions
How to Use Landmarks
How to use the screen keyboard
4 You see a keyboard on the screen (Figure 2-5).
Figure 2-5 Enter a Landmark
5 Use the keyboard appearing on the screen to enter the name, for
example:
CENTRAL OFFICE BOEBLINGEN.
You enter text on the keyboard by turning the Modify knob to
move to successive letters. When the letter you want is
highlighted, press the Modify knob. Continue this process until
you have the text you want.
NO T E If you have a keyboard attached to your OTDR, you can enter text
directly from the keyboard. You see the entered text in the edit field of
the screen keyboard.
6 Press the C
ONFIRM softkey to confirm your entry.
54
Elementary Sample Sessions
How to Use Landmarks
The landmark is now shown on the event bar and in the event
table.
How to Add a Landmark to the Event Table
If you want to add a landmark at an Event, you can either follow the
steps above, or add the landmark from the Event Table.
You add a landmark from the Event Table as follows.
1 If you cannot already see the Event Table, bring it up.
See “How to Display the Event Table” on page 51.
2 Turn the Modify knob to highlight the Event where you want to
add the landmark.
3 Follow steps 3 to 6 above.
The landmark name is added to the Event in the Event Table.
How to Modify the Name of an Existing Landmark
1 If you cannot already see the Event Table, bring it up.
See “How to Display the Event Table” on page 51.
2 Turn the Modify knob to highlight the Event that you want to
modify.
3 Press the bottom softkey until you see screen
4 Press the {A
M
ODIFY from the {ANALYSIS} menu.
5 Use the screen keyboard to modify the name.
See “How to use the screen keyboard” on page 54.
NALYSIS} softkey. Select LANDMARK – ADD/
1/3.
How to Delete Landmarks
Deleting a single landmark
1 If you cannot already see the Event Table, bring it up.
See “How to Display the Event Table” on page 51.
2 Turn the Modify knob to highlight the Event that you want to
55
Elementary Sample Sessions
How to Change the Vertical Offset
delete.
3 Press the bottom softkey until you see screen
4 Press the {A
from the {A
NALYSIS} softkey. Select LANDMARK – DELETE
NALYSIS} menu.
The landmark is deleted from the Event Bar and the Event
Tabl e.
Deleting All Landmarks
1 Press the bottom softkey until you see screen 1/3.
2 Press the {A
A
LL from the {ANALYSIS} menu.
NALYSIS} softkey. Select LANDMARK – DELETE
All landmarks are deleted from the Event Bar and the Event
Tabl e.
2.7 How to Change the Vertical Offset
The OTDR automatically adjusts the vertical offset so that you can
see most of the trace. You can change the vertical offset manually to
help you see specific points on the trace.
1/3.
NO T E See also “How to set 2 traces to the same vertical offset” on page 64.
You change the vertical offset as follows.
1 Press the bottom softkey until you see screen
2 Press the V.O
FFS. softkey
3/3.
3 Rotate the Modify knob to move the trace up or down.
4 Press the Modify knob or the C
ONFIRM softkey to confirm the
new vertical offset.
56
Elementary Sample Sessions
How to Print the Measurement
NO T E You cannot use the normal softkeys until you have set the new offset.
How to Restore the Automatic Offset
You return the Vertical Offset to its original value as follows.
1 Press the bottom softkey until you see screen
2 Press the V.O
Press the A
FFS. softkey
UTO softkey.
2.8 How to Print the Measurement
How to Print the Current Measurement
How to Set the Print Device and Layout
1 Press the bottom softkey until you see screen
2 Press the {C
3 Select the internal printer, if it is not already selected.
4 Press the {F
You see a list of what to include in your printout (T
E
VENT TABLE, MARKER INFORMATION, LOGO, and MEAS
P
ARAMETERS).
5 Select/Deselect what you want to print as appropriate.
ONFIG} softkey and select PRINT DEVICE.
ILE} softkey and select MODIFY PRINT LAYOUT.
3/3.
1/3.
RACE,
How to make the Print
6 Press the {F
T
RACE from the {FILE} menu.
ILE} softkey. Select PRINT TRACE – CURRENT
The measurement is printed after a short initialization period. In
addition to some statistical information, the print can show the
following (see step 5 above):
57
Elementary Sample Sessions
How to Print the Measurement
• The measurement parameters that show further trace
information, detailed instrument information, and the most
important parameters (range, pulsewidth, and so on).
• The trace.
• Information about the markers (position, attenuation, loss, and
so on).
• The event table.
This gives you all the information necessary to document the
measurement, or to repeat it using the same parameters.
How to Print All Measurements
To print the results of all measurements on the OTDR’s built-in
printer (if installed):
1 Select the internal print device and layout.
See “How to Set the Print Device and Layout” on page 57.
2 Press the P
RINT hardkey.
How to Print to an External Printer
1 Attach an external printer to your OTDR.
To see where the external printer slot is, see Figure 1-2 “The
Front Panel”.
2 Press the bottom softkey until you see screen
3 Press the {C
4 Select E
5 Press the {F
P
APER SIZE.
6 Select A4 or L
ONFIG} softkey and select PRINT DEVICE.
XTERNAL PRINTER.
ILE} softkey and select MODIFY PRINT LAYOUT -
ETTER as appropriate.
7 Print the Measurement(s)
See “How to make the Print” on page 57 or “How to Print the
Current Measurement” on page 57.
58
1/3.
Elementary Sample Sessions
How to Save the Measurement
2.9 How to Save the Measurement
This section describes how to save the results of the measurement.
Saving a measurement not only saves the results, but also saves the
parameter settings. When you recall the measurement later, you can
do further analysis or compare the saved measurement with
subsequent ones. You can also repeat the measurement using
exactly the same parameters as the first time.
You save the measurement as follows:
1 Press the bottom softkey until you see screen
1/3.
How to Specify the Storage Device
2 Press the {C
You see a submenu which allows you to select F
H
ARDDISK.
ONFIG} softkey and select STORAGE DEVICE.
LOPPY or
3 If you want to save to a disk, insert a floppy disk in the OTDR
floppy disk drive (see Figure 1-2) and select F
To save to the OTDR’s built-in hard disk, select H
LOPPY.
ARDDISK.
How to Specify the Bellcore Revision
4 Press the {F
ILE} softkey and select FILE TYPE.
You see a submenu which allows you to select the Bellcore
revision number used to store Bellcore files.
Bellcore revision 1.1 conforms to standards, but you may need
to use Bellcore revision 1.0 for backward compatibility.
5 Select B
ELLCORE REV. 1.0 or BELLCORE REV. 1.1 as appropriate.
How to Save the Trace
6 Press the S
AVE hardkey.
NOTE SAVE TRACE in the {FILE} menu has the same effect as the Save
hardkey.
59
Elementary Sample Sessions
How to Run a Manual Measurement
If you have already saved
a file using the command
F
ILE – SAVE AS, the OTDR
uses the last entered file
name and adds the
consecutive numbers
(“_nn”).
The measurement is then saved in a file. The OTDR automatically
names the file. The file name by default follows the scheme
Tmmdd_nn.SOR, where mm is the current month, dd is the current
date and nn is the consecutive number of the measurements saved
on that date.
How to Save to a User-Defined Name
1 Select the correct storage device.
See steps 1 to 3 above.
2 Press the {F
3 You see a screen keyboard.
4 Enter a new filename using the screen keyboard.
See “How to use the screen keyboard” on page 54.
ILE} softkey and select SAVE TRACE AS.
2.10 How to Run a Manual Measurement
When you already know about the fiber under test, you can set the
parameters exactly. This section describes how to setup and run a
measurement manually.
How to Change the Measurement Span
To set the measurement span to about 1.5 times the length of the
fiber:
1 Press the bottom softkey until you see screen
2 Press the S
3 Turn the modify knob to set the range of the measurement.
60
PAN softkey.
2/3.
Elementary Sample Sessions
How to Run a Manual Measurement
The value in the table beneath the trace changes as you turn the
knob.
Figure 2-6 Setting the Range
4 Press the knob to enter the value.
How to Change the Optimization Mode
To increase the dynamic range of the measurement, you select to
optimize for dynamic:
1 Press the bottom softkey until you see screen
2 Press the O
PTIMIZE softkey. The Optimize mode in the
3/3.
parameter window changes.
Continue pressing the O
D
YNAMIC.
PTIMIZE softkey until the mode is
NO T E Selecting SETTINGS - OPTIMIZE MODE - DYNAMIC from the 1/3 screen
is equivalent to selecting OPTIMIZE.
How to Run the Measurement
Now that you have set the range correctly, the measurement can be
run:
61
Elementary Sample Sessions
How to Display more than one trace
1 Press the RUN/STOP hardkey.
2 Wait for the trace to become free of noise (takes some seconds).
3 Press the R
Figure 2-7 The Trace of the Manual Measurement
UN/STOP hardkey.
The OTDR has automatically scanned the trace for events. These
events are shown in the event bar at the bottom of the trace.
2.11 How to Display more than one trace
1 Press the bottom softkey until you see screen 1/3.
2 Make the first trace
62
Elementary Sample Sessions
How to Display more than one trace
Either take the trace manually (RUN/STOP .. RUN/STOP),
or open an existing trace ({F
ILE} - OPEN).
3 Press the V
IEW softkey. Select CURRENT TRACE from the View
menu.
You see a list of 4 linestyles. The first is labelled with the name
of the current trace. The other 3 are labelled
4 Select one of the linestyles labelled
<empty>.
<empty>.
This corresponds to the new current trace.
5 Make a second measurement.
Either R
UN/STOP .. RUN/STOP or {FILE} - OPEN TRACE as
before. You now see 2 traces on the OTDR screen.
Figure 2-8 Two traces on the same picture
NO T E If you are opening an existing trace, there is an alternative way of
adding a new trace.
63
Elementary Sample Sessions
How to Display more than one trace
After you select {FILE} - OPEN TRACE, the first 4 softkeys correspond to
the 4 possible traces. Highlight the trace you want, and press one of the
softkeys labelled <empty>.
How to change the style of the current trace
1 Select the trace you want to change with {VIEW} - CURRENT
T
RACE.
2 Press the V
IEW softkey. Select PREFERENCES from the View
menu.
3 Select L
or C
INESTYLE to choose a new linestyle (SOLID or DOTTED),
OLOR to choose a new color (black, green, blue, or red).
How to set 2 traces to the same vertical offset
1 Press the bottom softkey until you see screen 3/3.
2 Select the trace you want to alter.
The fifth softkey is labelled with the name of the current trace.
You can press this softkey to toggle between the traces currently
displayed.
3 Press the V.O
FFS. softkey
You can now use the Modify knob to alter the vertical offset of
the current trace. When the 2 traces are level, confirm by
pressing the bottom softkey.
How to Close a Trace
1 Press the bottom softkey until you see screen 1/3.
2 Press the F
menu.
ILE softkey. Select CLOSE TRACE from the {FILE}
3 You see a list of the currently active traces, next to the line
sample used to represent them. Move to the trace you want to
close and select by pressing the Modify Knob.
64
Elementary Sample Sessions
How to Set Labels for Trace Information
NO T E If you want to close all the traces, select CLOSE ALL from the FILE
menu.
2.12 How to Set Labels for Trace Information
You can save up to five strings which are stored along with your
trace. By default these strings are accompanied by the labels
Cable Id, Fiber Id, Orig. Loc., Term. Loc. and
Operator.
How to view the Current Trace Information.
1 Press the bottom softkey until you see screen 1/3.
2 Press the {F
menu.
3 Select V
65
IEW ALL from the TRACE INFOS submenu.
ILE} softkey. Select TRACE INFOS from the {FILE}
Elementary Sample Sessions
How to Set Labels for Trace Information
You see a window showing the current labels and trace
information (Figure 2-9).
Figure 2-9 Current Trace Information
4 Press the Modify knob to close this window.
How to Enter new Trace Information
5 Bring up the Trace Infos window as before.
6 Select one of the strings from the Trace Infos submenu, for
example
You see a screen keyboard.
7 Enter the new information using the screen keyboard.
See “How to use the screen keyboard” on page 54.
8 Repeat this process for any other strings that you want to enter.
Comment.
How to Change the Trace Info Labels
The default names for the Trace Info Labels are Cable ID,
Fiber ID and so on. You change these labels as follows.
9 Press the bottom softkey until you see screen
66
1/3.
Elementary Sample Sessions
How to Set the Time and Date
10 Press the {CONFIG} softkey. Select TRACE INFO.LABELS
H
EADER from the {CONFIG} menu.
11 Select one of the labels from the Trace Infos submenu.
You see a screen keyboard.
12 Enter the new information using the screen keyboard.
See “How to use the screen keyboard” on page 54.
13 Repeat this process for any other labels that you want to alter.
2.13 How to Set the Time and Date
You can set the current Time and Date on your OTDR as follows.
1 Press the bottom softkey until you see screen
2 Press the {C
{C
ONFIG} menu.
You see a window showing the time and date currently set on
your OTDR (Figure 2-10).
Figure 2-10 Set the Time and Date
67
1/3.
ONFIG} softkey. Select DATE/TIME from the
Elementary Sample Sessions
How to Set the Time and Date
How to Change the Date
You see an arrow pointing at the Date edit field. The date is
displayed in the format day/month/year.
3 Press the Modify knob to confirm that you want to alter this
value.
4 Turn the Modify knob to alter the date.
Each turn of the Modify knob increases or decreases the date by
1 day.
5 Press the Modify knob to confirm the new date.
How to Change the Time.
6 Turn the Modify knob until you see an arrow next to the Time
edit field.
The date is displayed in the format hour:minute:second.
7 Press the Modify knob to confirm that you want to alter this
value.
8 Turn the Modify knob to alter the time.
Each turn of the Modify knob increases or decreases the time by
1 minute.
9 Press the Modify knob to confirm the new time
How to Confirm the new Time and Date
10 Turn the Modify knob so that there is an arrow next to OK.
11 Press the Modify knob to confirm.
NO T E If you do not want to make these changes, turn the Modify knob to
Cancel and press it.
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3
3 Further Sample Sessions
Further Sample Sessions
Chapter 2 “Elementary Sample Sessions” showed you how to
measure a trace, and to make simple settings.
This chapter contains further step-by step guides showing what you
can do to analyze a trace after it has been measured.
If you have not used an OTDR before, you should first read the
previous chapter. The equipment used in this chapter is the same as
before.
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Further Sample Sessions
How to Add an Event
3.1 How to Add an Event
How to Add a Reflective Event
The OTDR automatically scans the trace for Non-Reflective and
Reflective Events, but you can also add Events manually.
NO T E Adding an Event only makes sense after the measurement has stopped.
Otherwise, the automatic scanning will delete the event.
You add an Event to a trace as follows.
1 Press the N
EXT MARKER hardkey until marker C is highlighted.
Marker C is now the active marker.
2 Move Marker C to where you want to add the Event.
You move the active marker by turning the Modify knob.
3 Press the bottom softkey until you see screen 1/3.
4 Press the {A
the {A
You see a submenu, from which you can select N
R
EFLECTIVE EVENTS, REFLECTIVE EVENTS, or DECLARE FIBER
E
ND.
NALYSIS} softkey. Select ADD/MODIFY E VENT from
NALYSIS} menu.
ON-
NO T E Non-Reflective Events typically appear as a step on the trace; reflective
Events as a peak. See “Events” on page 27.
5 Select R
EFLECTIVE EVENTS.
NO T E If there is already an Event near marker C, you are asked whether you
want to modify this Event or add a new one.
In this case, select
Add by turning the Modify knob until Add is
highlighted, then press the Modify knob to confirm.
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Further Sample Sessions
How to Add an Event
You now see a guidance dialog beneath the trace, advising you what
you should now do.
How to Set the Level Markers for Reflectance
When you are adding a Reflective Event, you see 3 level-markers
with which you set the Reflectance (Figure 3-1).
Figure 3-1 Add Reflective Event: Level-Markers
You use to the level-markers set the Reflectance as follows.
6 Press the Modify knob to activate the first level marker.
The leftmost of the 3 dots turns into an
7 Turn the Modify knob to move the level-marker to the left.
You see a line between the first and second level-markers.
Make the line as long as possible, and as close to the path of the
trace as possible.
72
x to show it is active.
Further Sample Sessions
How to Add an Event
NO T E You should not move the level-marker left of any previous Events.
8 Press the knob to activate the second level-marker.
The second dot now turns to an
x.
9 Move the second level-marker just in front of the Event, that is
just in front of the position of marker C.
You may not move the level-marker to the right of marker C.
10 Press the Modify knob again to activate the third level-marker.
The third dot now turns into an
x.
11 Move the third level-marker to the peak of the reflection (see
Figure 3-2).
Figure 3-2 Add Reflective Event: Level-Markers set
12 Press the Modify knob again to confirm the Event.
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Further Sample Sessions
How to Add an Event
The new Event can now be seen in the Event Bar and the Event
Tabl e.
How to Set the Level Markers for Insertion Loss
You now see 4 level-markers with which you set the Insertion Loss
(Figure 3-3).
Figure 3-3 Add Non-Reflective Event: Level-Markers
You use the level-markers set the Insertion Loss as follows.
13 Press the Modify knob to activate the first level marker.
The leftmost of the 4 dots turns into an
14 Turn the Modify knob to move the level-marker to the left.
You see a line between the first and second level-markers.
Make the line as long as possible, and as close to the path of the
trace as possible.
74
x to show it is active.
Further Sample Sessions
How to Add an Event
NO T E You should not move the level-marker left of any previous Event.
15 Press the knob to activate the second level-marker.
The second dot now turns to an
x.
16 Move the second level-marker just in front of the Event, that is
just in front of the position of marker C.
You may not move the level-marker to the right of marker C.
17 Press the Modify knob again to activate the third level-marker.
The third dot now turns into an
x.
18 Move the third level-marker just behind the Event.
19 Press the Modify knob again to activate the fourth level-marker.
The fourth dot now turns into an
x.
20 Turn the Modify knob to move the level-marker to the right.
You see a line between the third and fourth level-markers.
Make the line as long as possible, and as close to the path of the
trace as possible (see Figure 3-4).
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Further Sample Sessions
How to Add an Event
NO T E You should not move the level-marker right of any subsequent Event.
Figure 3-4 Add Non-Reflective Event: Level-Markers set
21 Press the Modify knob again to confirm the Event.
The new Event can now be seen in the Event Bar and the Event
Tabl e.
How to Add a Non-Reflective Event
1 Follow steps 1 to 4 above.
2 Select N
NO T E If there is already an Event near marker C, you are asked whether you
want to modify this Event or add a new one.
76
ON-REFLECTIVE EVENT.
Further Sample Sessions
How to Measure Loss and Attenuation
In this case, select Add by turning the Modify knob until Add is
highlighted, then press the Modify knob to confirm.
You now see a guidance dialog beneath the trace, advising you what
you should now do.
Now follow the steps in “How to Set the Level Markers for
Insertion Loss” on page 74.
3.2 How to Measure Loss and Attenuation
How to Measure 2-Point Loss
You can use the OTDR to measure the loss between any two points
on a trace (for example, between two connectors).
You measure two-point loss as follows.
1 Press the N
EXT MARKER hardkey until marker A is active.
2 Move marker A to the left point.
3 Press the N
EXT MARKER hardkey again.
Marker B is now active.
4 Move Marker B to the right point.
5 Press the bottom softkey until you see screen
6 Press the {A
{A
NALYSIS} menu.
NALYSIS} softkey. Select 2-PT. LOSS from the
1/3.
The loss between Marker A and Marker B is shown in the Marker
Information window beneath the trace, next to the label
.
Loss
2-Pt.
NO T E To measure the Total Loss for the whole fiber, see “How to Measure the
Total Loss of a Fiber” on page 79.
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Further Sample Sessions
How to Measure Loss and Attenuation
How to Measure 2-Point Attenuation
If you want to know the average attenuation of your link (or parts of
it), you can measure the 2-point attenuation between markers A and
B.
You measure the 2-point attenuation as follows.
1 Position markers A and B at the points between which you want
to measure the attenuation.
See steps 1 to 4 above.
2 Press the bottom softkey until you see screen
3 Press the {A
the {A
NALYSIS} softkey. Select 2-PT. ATTENUATION from
NALYSIS} menu.
1/3.
The attenuation between Marker A and Marker B is shown in the
Marker Information window beneath the trace, next to the label
Pt. Att
.
2-
NO T E To measure the attenuation of the whole fiber, position Marker A on the
backscatter just after the initial reflection.
If there is a reflection at the fiber’s end, position Marker B in front of
the leading edge of the reflection, Otherwise, place Marker B just
before the trace bends into the noise.
How to Measure LSA Attenuation
As well as measuring 2-point attenuation, you can also measure the
LSA (Least Square Approximation) between markers A and B.
LSA us a statistical method which can be more accurate.
You measure the 2-point attenuation as follows.
1 Position markers A and B at the points between which you want
to measure the attenuation.
See steps 1 to 4 above.
NO T E Make sure that there is no splice or connector between the two markers.
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Further Sample Sessions
How to Measure the Total Loss of a Fiber
2 Press the bottom softkey until you see screen 1/3.
3 Press the {A
the {A
NALYSIS} softkey. Select LSA-ATTENUATION from
NALYSIS} menu.
The attenuation between Marker A and Marker B is shown in the
Marker Information window beneath the trace, next to the label
LSA-Att .
How to Measure Optical Return Loss
You measure the Optical Return Loss between two points as
follows.
1 Position markers A and B at the points between which you want
to measure the Optical Return Loss.
See steps 1 to 4 above.
NO T E Make sure that there is no splice or connector between the two markers.
2 Press the bottom softkey until you see screen
3 Press the {A
from the {A
NALYSIS} softkey. Select OPTICAL RETURN LOSS
NALYSIS} menu.
The Optical Return Loss between Marker A and Marker B is shown
in the Marker Information window beneath the trace, next to the
label
ORL.
1/3.
3.3 How to Measure the Total Loss of a Fiber
This section tells you how to examine the Total Loss of a fiber.
There are many other measurements that can be performed on the
OTDR (for example for attenuation, insertion loss, or reflectance).
You can find further examples in the online documentation.
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Further Sample Sessions
How to Measure the Total Loss of a Fiber
1 Press the NEXT MARKER hardkey until marker B is highlighted.
Marker B is now the active marker.
2 Move Marker B to where the backscatter and left rising edge of
the End Reflection meet (Figure 3-5).
You move the active marker by turning the Modify knob.
Figure 3-5 Measure Total Loss: Position Marker B
3 Press the Around Marker hardkey to check the position of
Marker B.
4 Place Marker B as close as possible to the left rising edge.
5 Press the F
6 Press the N
ULL TRACE hardkey to see the whole trace again.
EXT MARKER hardkey three times.
Marker A is now the active marker, and is highlighted.
7 Move Marker A to the far left, then press the A
hardkey to view the start of the fiber.
80
ROUND MARKER
Further Sample Sessions
How to Measure the Total Loss of a Fiber
You now see the deadzone from the front-panel reflection at the
start of the fiber.
8 Position Marker A so that it cuts the trace in the same vertical
position as the backscatter extrapolated back to 0 m (Figure 3-6).
This takes into account the loss in the deadzone.
Figure 3-6 Measure Total Loss: Position Marker A
9 Press the bottom softkey until you see screen
10 Press the {A
NALYSIS} softkey.
11 Select 2-Pt. Loss from the Analysis menu.
You see the two-point loss in the marker information window
below the trace.
81
1/3.
Further Sample Sessions
How to Take a Two-Way Measurement
3.4 How to Take a Two-Way Measurement
A two-way measurement lets you average two measurements, one
from each end of the fiber. This means you can calculate average
splice losses, and increase the splice loss accuracy.
You average a two-way measurement as follows.
1 Load two traces, one measured from each end of the fiber.
See “How to Display more than one trace” on page 62.
NOT E You must have only 2 traces loaded. If you have a third or fourth trace
loaded, you must close these traces.
See “How to Close a Trace” on page 64.
Both traces must have an Event Table. If a trace does not have
an Event Table, you should use the Scan Trace function. See
“How to Scan for Events” on page 49.
2 Press the bottom softkey until you see screen
3 Press the {A
M
EASUREMENT from the {ANALYSIS} menu.
NALYSIS} softkey. Select TWO-WAY
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1/3.
Further Sample Sessions
How to Take a Two-Way Measurement
You see the two traces reflecting each other (Figure 3-7).
Figure 3-7 Two-Way Measurement: traces
The softkey labels change to show you functions for two-way
measurement.
4 Use the markers to zoom on the traces (for example to select
synchronization points).
How to synchronize traces before Averaging
5 Press the H.OFFSET softkey.
6 Turn the Modify knob to move the current trace horizontally.
This lets you place a known point at the same position on the
each trace.
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Further Sample Sessions
How to Take a Two-Way Measurement
NO T E If you want to reuse the markers, press the MARKER softkey.
7 Press the T
WOWAY softkey to take the measurement.
The two traces are now averaged, and you see a third trace
showing the average.
The two-way measurement generates a two-way measurement
Event Table to show a comparison between the Events on the two
traces (Figure 3-8).
Figure 3-8 Two-Way Measurement: Event Table
84
Further Sample Sessions
How to Subtract One Measurement from Another
3.5 How to Subtract One Measurement from Another
You can make a general comparison of two different fibers by
subtracting one measurement from the other. This allows you to
instantly see the differences.
You subtract measurements as follows.
1 Load the two traces to be compared.
See “How to Display more than one trace” on page 62.
NOT E You must have only 2 traces loaded. If you have a third or fourth trace
loaded, you must close these traces.
See “How to Close a Trace” on page 64.
2 Press the bottom softkey until you see screen
3 Press the {A
M
EASUREMENT from the {ANALYSIS} menu.
The softkey labels change to show you functions for subtracting
a measurement.
4 Use the markers to zoom on the traces (for example to select
synchronization points).
NALYSIS} softkey. Select SUBTRACT
1/3.
How to Synchronize Traces before Subtracting
5 Press the H.OFFSET softkey.
6 Turn the Modify knob to move the current trace horizontally.
This lets you place a known point at the same position on the
each trace.
NO T E If you want to reuse the markers, press the MARKER softkey.
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Further Sample Sessions
How to Use Stored Settings
7 Press the SUBTRACT softkey to take the measurement.
The second trace is now subtracted, and you see a third trace
showing the differences (Figure 3-9).
Figure 3-9 Subtract Measurements: result
3.6 How to Use Stored Settings
If you want to prepare your OTDR for future measurements, you
can stored different parameter settings (for example, to measure
different types of links). The settings are stored in so-called settings
files.
The following parameters are stored: Start position and span,
Pulsewidth, Wavelength, Optimizing method, Averaging time,
86
Further Sample Sessions
How to Use Stored Settings
Refractive index, Scatter coefficient, Measurement mode, and
Event thresholds.
How to Store Parameter Settings
1 Press the bottom softkey until you see screen 1/3.
2 Press the {S
{S
ETTINGS} menu.
ETTINGS} softkey. Select STORE SETTINGS from the
You see a screen keyboard inviting you to enter a file name for
the settings file.
3 Enter a file name.
See “How to use the screen keyboard” on page 54.
The file name can be up to 8 characters long. If you do not
specify a file extension, it is given the default extension
How to Recall Stored Settings
After you have stored the settings, you can recall them for use with
subsequent measurements as follows.
1 Press the bottom softkey until you see screen
2 Press the {S
the {S
ETTINGS} softkey. Select RECALL SETTINGS from
ETTINGS} menu.
3 Turn the Modify knob to select the settings you want to recall.
NO T E You can also select DEFAULT.SET for the default settings or
LASTMEAS.SET for the settings from the previous measurement,
1/3.
.SET.
4 Press the Modify knob to confirm your selection.
How to Delete Stored Settings
You can delete stored settings which are no longer required as
follows.
87
Further Sample Sessions
How to Connect to the OTDR via LAN
1 Press the bottom softkey until you see screen 1/3.
2 Press the {S
{S
ETTINGS} menu.
ETTINGS} softkey. Select DELETE SETTINGS from the
NO T E If the current device is the floppy disk drive, you see a softkey called
HDD. If the current device is the hard disk drive, this softkey is called
FDD.
Select this softkey to move between the two devices.
3 Turn the Modify knob to highlight the settings you want to
delete.
4 Press the Modify knob to select the highlighted settings.
5 Press the C
ONFIRM softkey to confirm these settings.
The delete settings can no longer be recalled.
3.7 How to Connect to the OTDR via LAN
The OTDR is configured as a TCP/IP for Microsoft Networks and
compatible software.
You can connect the OTDR to a PC running such software. You do
not require a login name or password.
You connect to the OTDR as follows.
1 Install a LAN card in your OTDR.
For more details, please contact your system administrator. See
also “LAN Interface (Option 005)” on page 127.
2 Press the bottom softkey until you see screen
3 Press the {C
{C
ONFIG} menu.
ONFIG} softkey. Select LAN SETTINGS from the
1/3.
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Further Sample Sessions
How to Connect to the OTDR via LAN
You see a window where you can set the appropriate LAN
settings (Figure 3-10).
Figure 3-10 LAN Settings window
NO T E If you do not have a LAN card installed, the LAN SETTINGS menu
option is grayed.
4 Set the following parameters to those appropriate for your pc:
Station Name,
•
• either
•
•
•
Workgroup or Domain Name,
IP-Address,
Subnet Mask,
Gateway,
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Further Sample Sessions
How to Connect to the OTDR via LAN
• either WINS Name Server or DNS Name Server.
If you do not know any of these settings, please contact your system
administrator.
How to connect using Windows NT Explorer
You can now connect to the OTDR data directory as follows.
5 Start Windows NT Explorer
6 Select M
AP NETWORK DRIVE from the TOOLS directory.
7 Select your OTDR.
The OTDR will have the name you selected for
above.
Name
You can now select the OTDR directory, which is called
Station
DATA.
NOT E For DOS and Win 3.1, you must make a connection from the File
Manager or a DOS prompt.
To do this, you simply type:
net use o: \\<station-name>\DATA
where <station-name> is the name you selected for Station Name.
90
4
4 Macro Programming
Macro Programming
This chapter describes how to record and play macros for the
OTDR. This chapter also gives the syntax and the commands of the
macro language.
A macro is a means of storing commands you would otherwise give
to the OTDR manually. These commands can be repeated later.
Complex measurement procedures can thus be run automatically.
Detailed information on operating the OTDR, and thus on every
single command, can be found in the online documentation.
The macros are recorded in macro files that can be edited
afterwards. You can thus write macros that show messages on the
screen, that repeat commands in loops, and so on.
You can assign macros to the easy mode softkeys. The
inexperienced user in easy mode can thus start complex
measurements by pressing just one softkey.
92
Macro Programming
Recording Macros
4.1 Recording Macros
Recording a macro means storing commands you would otherwise
give to the OTDR manually. You can only start to record a macro
when a measurement is not running.
How to Record a Macro
To store commands by recording a macro:
While you are recording a
macro, any print
commands will only be
recorded, not executed.
1 Press the softkey C
2 In the config menu, select M
3 In the submenu on display, select S
ONFIG (screen 1/1).
ACRO RECORDER.
TART RECORDING.
4 Use the keyboard appearing on the screen to enter the name for
the macro file.
All subsequent commands entered into the OTDR will be
recorded in the macro file.
After you have entered all the commands:
5 Press the softkey C
6 In the config menu, select M
7 In the submenu on display, select S
ONFIG (screen 1/1).
ACRO RECORDER.
TOP RECORDING.
All the commands have now been stored in the macro file. You can
recall these by activating the macro. You can also edit the
commands in the macro file.
93
Macro Programming
Activating Macros
4.2 Activating Macros
Activating a macro gives you the chance to start complex
measurements with just one command. You can only activate
macros that have been recorded on the OTDR or created following
the macro command syntax.
How to Activate a Macro
In easy mode you can
activate macros by just
pressing the assigned
softkey.
To activate a stored macro:
1 Press the softkey C
2 In the config menu, select M
3 In the submenu on display, select P
ONFIG (screen 1/1).
ACRO RECORDER.
LAY MACRO.
The select-file dialog appears on the screen.
4 Turn the knob to select the macro to be activated.
5 Press the knob to confirm the selection.
The commands stored in the macro selected, are executed
successively.
How to Stop a Macro
If you wish to stop the execution before the macro has finished, you
have two possibilities, either halting or stopping the macro:
1 Press the softkey C
ONFIG (screen 1/1).
If you wish to stop the macro completely:
2 In the config menu, select M
ACRO RECORDER – STOP MACRO.
Alternatively: If you wish to halt the macro and continue later:
2 In the config menu, select M
ACRO RECORDER – HALT MACRO.
To continue the macro after halting:
3 In the config menu, select M
M
ACRO.
ACRO RECORDER – RESUME
94
Macro Programming
Editing Macros
4.3 Editing Macros
The recorded macros are stored on the OTDR’s internal hard disk.
You can copy the macro files on a diskette to edit them on your
personal computer. Use the command C
– C
OPY MACROS.
Use any text editor to edit the files without any formatting.
When editing a macro file, heed the following rules:
• A command cannot exceed one line unless you enter a line feed
in a string parameter.
• There can be more commands on one line, separated only by
blanks or tabs.
• Most commands are used with parameters. These have to be
separated by blanks. Strings have to be surrounded by straight
quotes ("...") and may have a maximum length of 40 characters.
ONFIG – MACRO RECORDER
• Tabs and spaces in front of commands are allowed.
• The macro interpreter does not distinguish between upper and
lower case letters in commands.
• Strings in arguments to commands are passed as they are (upper
and lower case).
• You can add comments to a macro using the
• The last command in a macro file always has to be
Rem command.
End.
95
Macro Programming
Macro Commands
4.4 Macro Commands
This section shows all the macro commands available.
In the syntax description you will find the following notations:
• The characters between angled brackets (<...>) show the names
of the parameters. You do not type these brackets in the actual
command.
• “<wsp>” stands for any white space character.
• The parts given in brackets ([...]) can be omitted.
Overview
The available commands can be divided into six groups:
Setting Parameters
• SetAutoMeasurement
• SetAveragingTime
• SetNonReflEventThreshold
• SetOptimization
• SetPulseWidth
• SetReflEventThreshold
• SetStartValue
• SetStopValue
• SetWaveLength
• SetMeasurementState
Running Measurements
• StartMeasurement
• StopMeasurement
• WaitForStopMeasurement
96
Macro Programming
Macro Commands
Documenting Measurements
• Load
• PrintAll
• PrintCurrent
• Save
• SaveAs
• SetComment
• SetCommentLabel
Changing the Display
• SetCurrentTrace
• SetDottedLines
• SetEventBar
• SetGrid
• SetLengthUnit
• SetTraceColor
• SetUserMode
Comments and Flow Control
• Goto
• Label
• LoopStart
• LoopEndCount
• Message
• Rem
• Sleep
• Troff
• Tron
97
Macro Programming
Macro Commands
Analyzing Measurements
• SetABReadOut
• SetActiveMarker
• SetAnalysisMode
• SetAutoOffset
• SetDisplayMode
• SetPosMarker
• SetReflexMarker
• SetSpliceMarker
• SetXScaleMode
• SetZoomA
• SetZoomB
• SetZoomC
• StartScan
• StopScan
Additional commands
• SetMacroDelay
• SetDefaultFileName
Commands For Setting Parameters
The measurement parameters can be set using the following macro
commands. The parameters are always valid for a certain trace. You
can simultaneously load up to four traces into the OTDR’s memory.
command SetAutoMeasurement
syntax SetAutoMeasurement<wsp><mode>[<wsp><trace-nr>]
description Lets the OTDR set itself up automatically to achieve best results.
parameters mode 0 – set parameters manually
1 – set parameters automatically
example
SetAutoMeasurement 1
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Macro Programming
Macro Commands
command SetAveragingTime
syntax SetAveragingTime<wsp><time>[<wsp><trace-nr>]
description Sets the duration of the measurement. A value of 0 means that the
measurement is not stopped automatically.
parameters time averaging time in s (values: 0...32760)
example
SetAveragingTime 0
command SetNonReflEventThreshold
syntax SetNonReflEventThreshold<wsp><threshold>[<wsp><trace-nr>]
description Sets the threshold for the OTDR when scanning for non-reflective
events on the trace.
parameters threshold threshold in mdB
related commands SetReflEventThreshold
example SetNonReflEventThreshold 50
command SetOptimization
syntax SetOptimization<wsp><method>[<wsp><trace-nr>]
description Selects the optimization method to be used.
parameters method 1 – standard
2 – resolution
3 – dynamic
4 – linearity
example
SetOptimization
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Macro Programming
Macro Commands
command SetPulseWidth
syntax SetPulseWidth<wsp><pwidth>[<wsp><trace-nr>]
description Sets the pulsewidth and thus the length and the power of the pulses
the OTDR launches into the fiber.
parameters pwidth pulsewidth in ns
(values: 10, 30, 100, 300, 1000, 3000, 10000)
example
SetPulseWidth 300
command SetReflEventThreshold
syntax SetReflEventThreshold<wsp><threshold>[<wsp><trace-nr>]
description Sets the threshold for the OTDR when scanning for reflective
events on the trace.
parameters threshold threshold in mdB
related commands SetNonReflEventThreshold
example
SetReflEventThreshold 50000
command SetStartValue
syntax SetStartValue<wsp><start>[<wsp><trace-nr>]
description Sets the distance of the first measured point on the trace from the
OTDR.
parameters start start position in mm
example
SetStartValue 1000000
100
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