Tektronix TFP2A Service Manual

Service Manual

TFP2A FiberMaster Optical Time-Domain Reflectometer

070–9188–03

Warning

The servicing instructions are for use by qualified personnel only. To avoid personal injury, do not perform any servicing unless you are qualified to do so. Refer to the Safety Summary prior to performing service.

First Printing: April 1997

Products of T ektronix, Inc. and its subsidiaries are covered by U.S. and foreign patents and/ or pending patents.

TEKTRONIX, TEK, and FiberMaster are registered trademarks of Tektronix, Inc. Printed in U.S.A. Specification and price change privileges are reserved.

WARNING

This equipment generates, uses, and can radiate radio-frequency energy, and if not installed and used in accordance with the instructions manual, may cause interference to radio communications. It has been tested and found to comply with the limits for a Class A computing device pursuant to Subpart J of Part 15 of FCC Rules, which are designated to provide reasonable protection against such interference when operated in a commercial environment. Operation of this equipment in a residential area is likely to cause interference, in which case, the user, at his or her own expense, will be required to take whatever measures may be required to correct the interference.

EC Declaration of Conformity

Tektronix Holland N.V. Marktweg 73A 8444 AB Heerenveen The Netherlands

declare under sole responsibility that the

TFP2A FiberMaster

meets the intent of Directive 89/336/EEC for Electromagnetic Compatibility. Compliance was demonstrated to the following specifications as listed in the official Journal of the European Communities:

EN 50081-1 Emissions

EN 55022 Radiated, Class B IEC 1000-3-2 Mains Current Harmonics

EN 50082-1 Immunity:

IEC 1000-4-2 Electrostatic Discharge IEC 1000-4-3 RF Radiated IEC 1000-4-4 Fast Transients IEC 1000-4-5 Surge IEC 1000-4-11 Dropout

Contacting Tektronix

Introduction

Phone 1-800-833-9200*

Address Tektronix, Inc.

Department or name (if known) 14200 SW Karl Braun Drive P.O. Box 500 Beaverton, OR 97077 USA

Web site www .tektronix.com

Sales support 1-800-833-9200, select option 1*

Service support 1-800-833-9200, select option 2*

Technical support Email: techsupport@tektronix.com

1-800-833-9200, select option 3* 1-503-627-2400

6:00 a.m. – 5:00 p.m. Pacific time

* This phone number is toll free in North America. After office hours, please leave a

voice mail message. Outside North America, contact a Tektronix sales office or distributor; see the Tektronix web site for a list of offices.

TFP2A FiberMaster Module-Level Service Manual

Safety Information ............................................................................. xi

1 Introduction: the FiberMaster OTDR...................................... 1-1

Product Description......................................................................................1-1

Using this Manual..........................................................................................1-4

Strategy for Servicing................................................................................1-4

Manual Structure.......................................................................................1-5

Manual Conventions.................................................................................1-5

Warranty Information....................................................................................1-6

Tektronix Service...........................................................................................1-7

Specifications................................................................................................1-8

Electrical Characteristics...........................................................................1-8

Operational Characteristics.....................................................................1-11

Physical Characteristics..........................................................................1-11

Environmental Characteristics ................................................................1-12

FS1300 Singlemode Optical Module ......................................................1-14

FS1500 Singlemode Optical Module ......................................................1-15

FS1315 Singlemode Optical Module ......................................................1-16

FG1300 Singlemode Optical Module......................................................1-17

FG1315 Singlemode Optical Module......................................................1-18

FL1300 Singlemode Optical Module.......................................................1-19

FL1500 Singlemode Optical Module.......................................................1-20

FL1315 Singlemode Optical Module.......................................................1-21

FM8500 Multimode Optical Module ........................................................1-22

FM1300 Multimode Optical Module ........................................................1-23

FM8513 Multimode Optical Module ........................................................1-24

Accessories and Options ...........................................................................1-25

Mainframes.............................................................................................1-25

Accessories.............................................................................................1-25

Options....................................................................................................1-26

Unpacking and Preparation for Use ..........................................................1-29

Preparation for Use.................................................................................1-29

Storage ...................................................................................................1-35

Repacking for Shipment..........................................................................1-35

Recalibration................................................................................................1-36

2 General Operating Instructions.............................................. 2-1

Overview of FiberMaster Operation.............................................................2-2

The Acquisition Screen.............................................................................2-4

Basic Operating Procedures........................................................................2-8

TFP2A FiberMaster Module-Level Service Manual v

Table of Contents

3 Theory of Operation ................................................................ 3-1

A1 - Control....................................................................................................3-1

Host Processor .........................................................................................3-1

Display Processor.....................................................................................3-1

Timebase..................................................................................................3-2

Signal Averager ........................................................................................3-2

A2 - Front Panel.............................................................................................3-3

Front Panel ...............................................................................................3-3

A3 - Power Supply.........................................................................................3-3

A4 - Interconnect...........................................................................................3-3

Interconnect..............................................................................................3-3

A5 - Module Support .....................................................................................3-4

Digital Interface and Cooler Power Supplies ............................................3-4

Mask Generator........................................................................................3-4

Strobe Continuation..................................................................................3-4

A6 - Printer Assembly...................................................................................3-5

Printer-Power Distribution.........................................................................3-5

A7 - Display Assembly..................................................................................3-5

Display......................................................................................................3-5

A20/A30 - Optical Plug-in..............................................................................3-5

4 Maintenance.............................................................................4-1

Product Service.........................................................................................4-1

Static-Sensitive Components....................................................................4-2

Inspection and Cleaning Procedures..........................................................4-3

Exterior Inspection....................................................................................4-3

Exterior Cleaning ......................................................................................4-4

Optical-Fiber Cleaning..............................................................................4-4

Interior Inspection .....................................................................................4-6

Interior Cleaning........................................................................................4-7

Lubrication ................................................................................................4-7

Terminal Interface..........................................................................................4-8

Functional Tests..........................................................................................4-10

Mainframe Checks..................................................................................4-10

Performance Verification............................................................................4-16

Equipment Required...............................................................................4-16

Clock Frequency.....................................................................................4-16

Verify Clock Phase..................................................................................4-17

Front-Panel Loss.....................................................................................4-18

Dynamic Range ......................................................................................4-20

Dead Zone (Attenuation).........................................................................4-32

Dead Zone (Event)..................................................................................4-34

Displayed Noise <0.030 dB (FS/FG series only) ....................................4-36

Zero Distance Accuracy..........................................................................4-38

Vertical System Linearity ........................................................................4-40

Optical Output Amplitude........................................................................4-56

vi TFP2A FiberMaster Module-Level Service Manual

Table of Contents

Adjustments.................................................................................................4-60

Control Board Adjustments.....................................................................4-60

Printer Board Adjustment........................................................................4-62

Display Adjustments ...............................................................................4-64

Troubleshooting and Diagnostics .............................................................4-70

Using the Diagnostics Menus .................................................................4-70

Troubleshooting Flowchart......................................................................4-71

Removal and Replacement Procedures....................................................4-75

Covers and Front Panel..........................................................................4-77

Back-Panel Assembly and Plug-In Optical Modules...............................4-79

Control Board..........................................................................................4-80

Printer Tray and Printer...........................................................................4-82

CRT, Color Shutter/Monochrome Filter, and Display Board...................4-83

PSI Power Supply (AC only)...................................................................4-87

IPD Power Supply and DC Power Option...............................................4-89

MDI Power Supply and DC Power Option ..............................................4-95

Disk Drive................................................................................................4-98

Module Support Board............................................................................4-99

Interconnect Board................................................................................4-100

Fan........................................................................................................4-101

Power Switch, Wire Set, and Line Filter................................................4-103

5 Replaceable Parts List ............................................................ 5-1

Parts Ordering Information...........................................................................5-1

Module Replacement................................................................................5-1

Using the Replaceable Parts List.................................................................5-2

Tektronix Part Number..............................................................................5-2

Serial/Model No. .......................................................................................5-2

Name and Description ..............................................................................5-2

Mfr. Code and Part Number......................................................................5-2

A Performance Verification Data Sheets...................................A-1

Optical Test Summary Data Sheet—FS1315 Singlemode ...................... A-2

Optical Test Summary Data Sheet—FG1315 Singlemode...................... A-3

Optical Test Summary Data Sheet—FL1315 Singlemode....................... A-4

Optical Test Summary Data Sheet—FM8513 Multimode........................A-5

B GPIB and RS-232 Connections...............................................B-1

C Firmware Features...................................................................C-1

D Error Codes..............................................................................D-1

TFP2A FiberMaster Module-Level Service Manual vii

List of Illustrations

Figure 1-1. Connector Options ..........................................................................1-28

Figure 1-2. Installing Optical Modules ..............................................................1-30

Figure 1-3. Interconnect Circuit Board Connectors.........................................1-31

Figure 1-4. Installing the Module Spacer: Two-Module Configuration...........1-32

Figure 1-5. Front-Panel Option Covers .............................................................1-33

Figure 1-6. Loading Paper into the Internal Printer .........................................1-34

Figure 2-1. Features on the Acquisition Screen.................................................2-4

Figure 2-2. Acquisition Screen Expansion—Overview (top),

Figure 2-3. Front Panel Overview ........................................................................2-8

Figure 2-4. Back Panel..........................................................................................2-9

Figure 4-1. Cleaning and Changing the Universal Connector ..........................4-5

Figure 4-2. Terminal Interface Connector...........................................................4-9

Figure 4-3. The Start-Up Screen ........................................................................4-10

Figure 4-4. Front-Panel Loss..............................................................................4-17

Figure 4-5. Dynamic Range Measurements......................................................4-19

Figure 4-6. Measuring the Backscatter .............................................................4-27

Figure 4-7. Noise Acquisition.............................................................................4-28

Figure 4-8. Measuring the Noise Floor..............................................................4-30

Figure 4-9. Dead Zone (Attenuation) Measurement.........................................4-31

Figure 4-10. Dead Zone (Event) Measurement .................................................4-33

Figure 4-11. Loss Cursors Measuring Noise....................................................4-36

Figure 4-12. Zero Distance Measurement.........................................................4-38

Figure 4-13. Two Acquisitions with Loss Variations .......................................4-40

Figure 4-14. Waveforms Superimposed: Variation in Fiber............................4-41

Figure 4-15. Waveforms Superimposed: Variation in Vertical System..........4-42

Figure 4-16. Variation Superimposed on Linear Backscatter.........................4-43

Figure 4-17. Two-Point Cursors Parallel to Waveforms ..................................4-44

Figure 4-18. Measuring Positive Non-Linearity................................................4-45

Figure 4-19. Measuring Negative Non-Linearity...............................................4-46

Figure 4-20. Test Set-Up with Optical Attenuator ............................................4-47

Figure 4-21. Backscatter on Reference Waveform ..........................................4-48

Figure 4-22. Test Set-Up with Optical Attenuator ............................................4-51

Figure 4-23. VCO Tune Voltage Adjustment.....................................................4-60

Figure 4-24. Printer Board Adjustment .............................................................4-61

Figure 4-25. Display Board Voltage Adjustment..............................................4-64

Figure 4-26. CRT Ring Magnet and Yoke Adjustments ...................................4-66

Figure 4-27. Display Board Video Adjustments ...............................................4-68

Figure 4-28. Run Diagnostics Menu ..................................................................4-69

Figure 4-29. Set Options Menu ..........................................................................4-70

Figure 4-30. Connector Orientation...................................................................4-75

Figure 4-31. Removing Instrument Covers.......................................................4-76

and Expanded View (bottom)....................................................2-5

viii TFP2A FiberMaster Module-Level Service Manual

List of Illustrations

Figure 4-32. Removing Front-Panel Assembly.................................................4-77

Figure 4-33. Removing the Back-Panel Assembly and Plug-In

Optical Module(s).....................................................................4-78

Figure 4-34. Removing the Control Board........................................................4-80

Figure 4-35. Removing the Printer Assembly...................................................4-81

Figure 4-36. Removing the Color Shutter .........................................................4-82

Figure 4-37. Removing the Monochrome Filter................................................4-83

Figure 4-38. Detaching the Display Board........................................................4-84

Figure 4-39. Detaching the CRT and Removing the

CRT/Display Assembly............................................................4-85

Figure 4-40. Removing the PSI Power Supply..................................................4-86

Figure 4-41. Disconnecting the PSI Power Supply ..........................................4-87

Figure 4-42. Removing the IPD Power Supply .................................................4-88

Figure 4-43. Disconnecting the IPD Power Supply..........................................4-89

Figure 4-44. Disconnecting the Line Filter Assembly......................................4-90

Figure 4-45. Removing the Line Filter Assembly.............................................4-91

Figure 4-46. Removing the DC Interlock Ring..................................................4-92

Figure 4-47. Removing the DC Filter Board......................................................4-93

Figure 4-48. Removing the MDI Power Supply.................................................4-94

Figure 4-49. Disconnecting the MDI Power Supply .........................................4-95

Figure 4-50. Removing the MDI DC Option......................................................4-96

Figure 4-51. Removing the Floppy-Disk Drive..................................................4-97

Figure 4-52. Removing the Module Support Board .........................................4-98

Figure 4-53. Detaching the Interconnect Board ...............................................4-99

Figure 4-54. Detaching the Air Baffle and Fan from the Back Panel............4-100

Figure 4-55. Detaching the Fan from the Back Panel ....................................4-101

Figure 4-56. Removing the Power Switch Coupler ........................................4-102

Figure 4-57. Removing the Power Switch Bracket.........................................4-103

Figure 4-58. Detaching the Ground Wires from the Chassis ........................4-103

Figure 4-59. Removing the Line Filter and Wire Set ......................................4-104

Figure 5-1. Electrical Module Overview ..............................................................5-5

Figure 5-2. Case ....................................................................................................5-6

Figure 5-3. Front Panel .........................................................................................5-8

Figure 5-4. Chassis with CRT and Circuit Boards ...........................................5-10

Figure 5-5. Power Supply: PSI ...........................................................................5-11

Figure 5-6. Power Supply: IPD...........................................................................5-13

Figure 5-7. Power Supply: MDI ..........................................................................5-14

Figure 5-8. Chassis-Mounted Electrical Parts..................................................5-16

Figure 5-9. Back ..................................................................................................5-17

Figure 5-10. Thermal Printer with Cables .........................................................5-18

Figure 5-11. Internal RAM...................................................................................5-19

Figure 5-12. DC Power: Option 17 (PSI and IPD)..............................................5-21

Figure 5-13. DC Power: Option 17 (MDI) ...........................................................5-23

Figure 5-14. Disk Drive Assembly .....................................................................5-24

Figure C-1. Firmware Version Number on the Start-Up Screen.......................C-1

TFP2A FiberMaster Module-Level Service Manual ix

List of Tables

Table 1-1. Display Range—Vertical System .......................................................1-8

Table 1-2. Display Range—Horizontal System...................................................1-9

Table 1-3. Display..................................................................................................1-9

Table 1-4. Keyboard..............................................................................................1-9

Table 1-5. Hardcopy............................................................................................1-10

Table 1-6. Mass Storage .....................................................................................1-10

Table 1-7. Operational Characteristics..............................................................1-11

Table 1-8. Physical Characteristics...................................................................1-11

Table 1-9. Environmental Characteristics.........................................................1-12

Table 1-10. FS1300 Singlemode Optical Module..............................................1-14

Table 1-11. FS1500 Singlemode Optical Module..............................................1-15

Table 1-12. FS1315 Singlemode Optical Module..............................................1-16

Table 1-13. FG1300 Singlemode Optical Module .............................................1-17

Table 1-14. FG1315 Singlemode Optical Module .............................................1-18

Table 1-15. FL1300 Singlemode Optical Module..............................................1-19

Table 1-16. FL1500 Singlemode Optical Module..............................................1-20

Table 1-17. FL1315 Singlemode Optical Module..............................................1-21

Table 1-18. FM8500 Multimode Optical Module................................................1-22

Table 1-19. FM1300 Multimode Optical Module................................................1-23

Table 1-20. FM8513 Multimode Optical Module................................................1-24

Table 1-21. Mainframe Options..........................................................................1-25

Table 1-22. Standard Accessories.....................................................................1-25

Table 1-23. Optional Accessories......................................................................1-25

Table 1-24. System Options ...............................................................................1-26

Table 1-25. System Multimode Options ............................................................1-26

Table 1-26. System Singlemode Options..........................................................1-27

Table 1-27. Option Accessories.........................................................................1-27

Table 4-1. External Inspection Checklist ............................................................4-3

Table 4-2. Internal Inspection Checklist..............................................................4-6

Table 4-3. Dynamic Range Pulse Width and Distance Span...........................4-30

Table 4-4. Distance Accuracy Tolerance ..........................................................4-38

Table 4-5. Small Linearity Pulse Width Settings ..............................................4-51

Table 4-6. Loss Measurement Accuracy Pulse Width Settings......................4-53

Table 4-7. Tools Required for Module-Level Maintenance and Repair ..........4-75

Table B-1. GPIB Connections .............................................................................B-1

Table B-2. RS-232 Connections (DCE)...............................................................B-2

Table C-1. Firmware Versions and Features .....................................................C-2

Table D-1. File System Error Codes ...................................................................D-1

Table D-2. Flash Memory Error Codes...............................................................D-3

Table D-3. LED Error Codes................................................................................D-4

Table D-4. Phase 1 Error Codes..........................................................................D-5

Table D-5. Phase 2 Error Codes..........................................................................D-5

x TFP2A FiberMaster Module-Level Service Manual

Safety Information

The general safety information in these pages is for both operating and servicing personnel. In addition, specific warnings and cautions appear throughout the manual where they apply.

Definition of Terms and Symbols

In this manual, a CAUTION flag identifies a potential for equipment or other property damage.

A WARNING flag identifies a potential for personal injury or property damage. A DANGER flag identifies an immediate hazard to personal safety or property. Symbols that may be marked on the equipment indicate the following:

DANGER—High Voltage

Power Source

This product is designed to operate from a power source that will not apply more than 250 volts RMS between the supply conductors or between the supply conductor and ground. A protective ground connection by way of the grounding conductor in the power cord is essential for safe operation.

ATTENTION—refer to manual

Protective ground (earth) terminal

TFP2A FiberMaster Module-Level Service Manual xi

Safety Summary

Grounding the Instrument

The instrument is grounded through the grounding conductor of the power cord. To avoid electric shock, plug the power cord into a properly wired receptacle before connecting to the product input or output terminals.

Danger Arising from Loss of Ground

If you lose the protective ground connection, all accessible conductive parts (including knobs and controls that appear to be insulating) can render an electric shock.

Use the Proper Power Cord

Use only the power cord and connector specified for your product. Use only a power cord in good condition. Refer cord and connector changes to qualified service personnel.

Use the Proper Fuse

To avoid fire hazard, use only a fuse of the correct type, voltage rating, and current rating as specified in the parts list for your product. Refer fuse replacement to qualified service personnel.

Do Not Operate in Explosive Atmospheres

To avoid explosion, do not operate this product in an explosive atmosphere unless it has been specifically certified for such operation.

Do Not Remove Covers or Panels

To avoid personal injury, do not remove the product covers or panels. Do not operate the product without the covers or panel properly installed.

Laser Radiation

Avoid eye exposure to the laser output and open-ended fibers by covering the end or directing the output at a non-reflective surface.

Class 1 laser product under the Radiation Control and Health Safety Act of 1968.

Repair

Refer all repair problems to qualified service personnel.

FiberMaster has been classified as a

xii TFP2A FiberMaster Module-Level Service Manual

1 Introduction:

the FiberMaster OTDR

ATTENTION!

Read the Safety Information section located at the front of this manual before operating or servicing FiberMaster.

If you have questions about using or servicing FiberMaster, or have special application problems, in the U.S. and Canada call our toll-free help line,

1-800-835-9433, or contact your local Tektronix representative.

Product Description

The TEKTRONIX TFP2A FiberMaster Optical Time-Domain Reflectometer (OTDR) is

an optical-fiber test instrument capable of measuring loss characteristics and displaying faults, splices, and other fiber events in singlemode and multimode optical fibers.

FiberMaster applies pulses of light to the fiber under test via the optical output

connector. As the pulses travel through the fiber, some light is reflected back to the instrument. These reflections are processed to display a visual representation of the fiber on FiberMaster’s cathode ray tube (CRT), where you can make distance and loss measurements on the fiber under test.

The CRT display is a time plot, read from left to right. The trace starts with the

outgoing pulse, and the time difference is converted to distance in the measurement process. When you view a typical fiber display, events that are further down the fiber appear to the right (later in time). Loss is measured on the CRT’s vertical scale.

NOTE

TFP2A FiberMaster Module-Level Service Manual 1-1

This manual explains how to maintain the TFP2A FiberMaster product line, which includes mainframe models TFP2A (color monitor) and TFP2AM (monochrome monitor), configured with various options. (Refer to appendix A,

Options

"FiberMaster" or "TFP2A," to refer to both the TFP2A and TFP2AM models.

.) In this manual, the instrument is referred to generically as

Accessories and

Chapter 1: Introduction

Modular, Plug-In Laser Sources

❏ The FiberMaster OTDR was designed using a modular approach that allows you

to choose options that answer your specific test and measurement applications. You can upgrade your instrument configuration as your system requirements change. FiberMaster can accommodate 850-nanometer (nm) multimode, 1300nm multimode, 1310-nm singlemode, and 1550-nm singlemode laser sources in one or two plug-in modules. The modules can contain either two singlemode or two multimode lasers, or any single laser, allowing the instrument to be configured with one to all four wavelengths.

❏ Temperature-controlled laser light sources ensure stable wavelength and optical

output for highly accurate measurements.

Accurate, High-Speed Data Acquisition and Measurement

❏ The internal 32-bit microprocessor performs up to 16 million high-speed

averages per acquisition, maximizing the signal-to-noise ratio, giving a clear display of fiber events.

❏ FiberMaster measures a specific fiber feature, with single-keystroke

convenience. In addition, manual adjustments provide extended flexibility in interpreting the fiber data.

❏ An expand function allows you to magnify any portion or feature on the displayed

fiber acquisition.

❏ FiberMaster’s high-density acquisition capability offers extended expansion

capacity and highly accurate measurements.

❏ A masking function can be performed automatically, or you can set manual

masks to reduce dead zones caused by large Fresnel reflections, improving measurement resolution.

Automatic and Manual Event Marking

❏ The instrument’s event-marking function automatically locates and measures

events on the fiber under test that have splice losses above a user-specified threshold, or you can also mark events manually.

❏ An event table is compiled displaying the measurements for each marked event.

You can edit and print out this table, plus enter notes and mapping information about each event.

1-2 TFP2A FiberMaster Module-Level Service Manual

Extended Memory and Storage Capacity

❏ FiberMaster offers both a current memory, containing the current data

acquisition, and a reference memory, for previously acquired fiber waveform data. A dual-trace mode makes it possible to display the contents of both current and reference memory simultaneously, allowing you to compare a current optical-fiber acquisition to historical data.

❏ Mass-storage devices (the standard floppy-disk drive and optional internal RAM)

permit unlimited storage of waveform and settings data on both removable and internal media.

Hardcopy Options

❏ You can choose the optional high-speed internal thermal printer, or use

FiberMaster with either an IEEE 488 general-purpose interface bus (GPIB) external plotter or printer, or an RS232 external plotter or printer. One press of a button on the instrument’s front panel provides a 15-second hard copy of the displayed waveform and instrument settings on the internal printer.

Chapter 1: Introduction

Remote Control Capability

❏ The FiberMaster OTDR can be operated under the remote control of an

instrument controller or a computer with a GPIB interface, using an IEEE 488 general-purpose interface bus, or via the RS-232 serial interface.

Additional Features

❏ An easy-to-use menu system simplifies setting instrument measurement

parameters.

❏ You can upload and download waveform and settings data using the RS232

interface and XModem protocol.

❏ The 7-inch diagonal, high-resolution color or monochrome CRT provides a

comprehensive on-screen readout of waveform and measurement data, and instrument settings.

❏ Online help displays context-sensitive operator assistance at the press of a

button.

❏ Rugged, portable construction is also lightweight—under 35 pounds (15

kilograms).

TFP2A FiberMaster Module-Level Service Manual 1-3

Chapter 1: Introduction

Using this Manual

This manual is for servicing the TFP2A FiberMaster OTDR. To prevent injury to

yourself or damage to the OTDR, do not attempt service unless:

❏ You are a qualified service person, ❏ You have read the

manual.

❏ You have read the

When using this manual for servicing, be sure to observe all warnings, cautions, and

notes.

Strategy for Servicing

NOTE

Throughout this manual, any field-replaceable component, assembly, or part of this optical time-domain reflectometer is referred to generically as a module.

This manual contains all the information needed for periodic maintenance of the

FiberMaster OTDR, as well as all information for corrective maintenance down to the module level. This means that the procedures, diagrams, and other troubleshooting aids help isolate failures to a specific module, rather than to components of that module. Once a failure is isolated, replace the module with a new unit obtained from the factory.

All modules are listed in chapter 5,

module, use the fault isolation procedures given in chapter 4, remove and replace any failed module, follow the instructions in the same chapter.

Operator and Service Safety Summary

Strategy for Servicing

Replaceable Parts

section in this chapter.

. To isolate a failure to a

at the beginning of this

Maintenance

. To

1-4 TFP2A FiberMaster Module-Level Service Manual

Manual Structure

The FiberMaster Module-Level Service Manual consists of six chapters and two

appendices, containing the following information:

Chapter 1: Introduction

❏ Chapter 1,

unpacking and repacking instructions, and instrument specifications.

❏ Chapter 2,

front- and rear-panel controls and connectors, at a level appropriate for servicing the instrument. (For complete operating instructions, refer to the

User Manual

❏ Chapter 3,

instrument’s operation, as well as a block-level diagram.

❏ Chapter 4,

corrective maintenance on the FiberMaster, including inspection and cleaning, performance verification and adjustment, troubleshooting, and module removal and replacement procedures.

❏ Chapter 5,

and exploded-view drawings of their locations in the instrument.

❏ Chapter 6, ❏ Appendices include data sheets for recording instrument performance

information, GPIB and RS232 connection tables, instructions on upgrading firmware, and a listing of error codes.

Manual Conventions

Introduction

, provides a description of the FiberMaster OTDR,

General Operating Instructions

Theory of Operation

Maintenance

, contains the information needed to do periodic and

Replaceable Parts

Diagrams

, contains module-level block diagrams.

, contains a block-level description of the

, includes a list of module-level replaceable parts

, describes the functions of each of the

FiberMaster

This manual uses certain conventions that you should be familiar with before doing

service.

Terminology used in the FiberMaster manuals is in accordance with industry practice.

Abbreviations are in accordance with ANSI Y1.1-1972, with exceptions and additions explained in parentheses after the abbreviation. Graphic symbology is based on ANSI Y32.2-1975. Logic symbology is based on ANSI Y32.14-1973 and manufacturers’ data books or sheets. A copy of ANSI standards can be obtained from the Institute of Electrical and Electronic Engineers, New York, New York 10017.

Modules

Throughout this manual, any replaceable component, assembly, or part of the

FiberMaster OTDR is referred to generically as a module. In general, a module is an assembly, (e.g., a circuit board), rather than a component, (e.g., a resistor or integrated circuit).

TFP2A FiberMaster Module-Level Service Manual 1-5

Chapter 1: Introduction

Warranty Information

Tektronix warrants that this product will be free from defects in materials and

workmanship for a period of one (1) year from the date of shipment. If any such product proves defective during this warranty period, Tektronix, at its option, either will repair or replace the defective product without charge for parts and labor, or will provide a replacement in exchange for the defective product.

In order to obtain service under this warranty, the customer must notify Tektronix of

the defect before the expiration of the warranty period and make suitable arrangements for the performance of service. The customer shall be responsible for packaging and shipping the defective product to the service center designated by Tektronix, with shipping charges prepaid. Tektronix shall pay for the return of the product to the customer if the shipment is to a location within the same country as the service center. The customer shall be responsible for paying all shipping charges, duties, taxes, and any other charges for products returned to any other locations.

This warranty shall not apply to any defect, failure or damage caused by improper

use or improper or inadequate maintenance and care. Tektronix shall not be obligated to furnish service under this warranty a) to repair damage resulting from attempts by personnel other than Tektronix representatives to install, repair, or service the product; b) to repair damage resulting from improper use or connection to incompatible equipment; c) to repair any damage or malfunction caused by the use of non-Tektronix supplies; or d) to service a product that has been modified or integrated with other products when the effect of such modification or integration increases the time or difficulty of servicing the product.

This warranty is given by Tektronix with respect to this product in lieu of any other

warranties, express or implied. Tektronix and its vendors disclaim any implied warranties of merchantability or fitness for use for a particular purpose. Tektronix’ responsibility to repair or replace defective products is the sole and exclusive remedy provided to the customer for breach of this warranty. Tektronix and its vendors will not be liable for any direct, special, incidental, or consequential damages irrespective of whether Tektronix or the vendor has advance notice of the possibility of such damages.

1-6 TFP2A FiberMaster Module-Level Service Manual

Tektronix Service

Tektronix provides service to cover repairs under warranty as well as other services

that may provide a cost-effective answer to your service needs. Tektronix service technicians, trained on Tektronix products, are best equipped to service your FiberMaster OTDR. Our technicians are appraised of the latest information on improvements to the product, as well as the latest new options available.

Warranty Service

Tektronix warrants this product for one year from date of purchase. Tektronix

technicians provide all warranty service at the factory during this period. Contact your local Tektronix representative for more information.

Self Service

Tektronix supports repair to the module level by providing module exchange and

module repair and return services.

Chapter 1: Introduction

NOTE

Module-level service is available only for selected modules, under specific conditions. In the U.S. and Canada call 1-800-835-9433 for assistance with module exchange and repair, or contact your local Tektronix representative.

Module Exchange—this service reduces downtime for repair by allowing you to

exchange most modules for remanufactured ones. Tektronix ships you an updated and tested exchange module from the Redmond, Oregon service center within 24 hours. Each module comes with a 90-day service warranty.

Module Repair and Return—This service returns your module to you within 10 days.

The module you send to Tektronix is repaired, tested, and returned to you from the Redmond, Oregon service center. It is not updated to match current modules of the same type. Again, each module comes with a 90-day service warranty.

For More Information

In the U.S. and Canada, call 1-800-835-9433 for more information on warranty and

service for the FiberMaster OTDR, or contact your local Tektronix representative.

TFP2A FiberMaster Module-Level Service Manual 1-7

Chapter 1: Introduction

Specifications

Electrical Characteristics

The following characteristics and features apply to the FiberMaster OTDR mainframe

after a warmup period of at least 15 minutes. All loss numbers reflect one-way measurements unless otherwise specified.

Table 1-1. Display Range—Vertical System

Vertical range

Loss measurements

Loss readout resolution

Accuracy

Two point, splice loss, and LSA fiber loss:

FM/FS/FG series

FL series

1 dB to 50 dB, overview 1 dB to 100 dB, expanded view

0.001 dB to 0.01 dB

±0.05 dB/dB, from 7 dB above the RMS noise floor (SNR = 1) to 30 dB on the screen. Maximum error of ±0.2 dB from +7 dB above the RMS noise floor to top of backscatter.

±0.02 dB/dB, from 15 dB to 35 dB on the screen.

1-8 TFP2A FiberMaster Module-Level Service Manual

Table 1-2. Display Range—Horizontal System

Chapter 1: Introduction

Distance range Distance measurements

Cursor resolution (min) FM/FS/FG series:

850 nm MM

1300 nm MM/ 1310 nm SM/ 1550 nm SM

FL series:

1310 SM/

1550 SM Index of refraction range Distance measurement

accuracy

Number of displayed waveform points

1 m to 200 km

5 cm to 2 m, normal density; 1 cm to 50 cm, high density

20 cm to10 m, normal density; 10 cm to 2 m, high density

2 m to 10 m, normal density; no high density

1.4000 to 1.6000

±0.001%, ±minimum cursor resolution ±uncertainty in index of refraction

>16,000 maximum for each normal and high density

Table 1-3. Display

Size Resolution Display type

Color Monochrome

Table 1-4. Keyboard

Connector Compatibility

7 inches (17.5 cm) diagonal 640 by 480 pixels

Two-color system giving three colors, with five levels each Five-level gray scale

5-pin RJ11 Compatible with IBM AT keyboards (input

only), but complete compatibility can be guaranteed only with Tektronix keyboard Option 19

TFP2A FiberMaster Module-Level Service Manual 1-9

Chapter 1: Introduction

Table 1-5. Hardcopy

Internal printer

Resolution Print dimensions

External plotter

External printer

Table 1-6. Mass Storage

Floppy disk drive

Size Capacity Format

Internal RAM

Capacity

High-speed, high-resolution dot matrix, thermal 150 dots/in vertical and horizontal 4 in by 5 in (10.2 cm by 12.7 cm)

HP-GL compatible (Tektronix HC100): GPIB and RS-232 connections

Epson FX-compatible: RS232 connection Hewlett-Packard ThinkJet-compatible: GPIB and RS-232 connections PostScript-compatible: RS-232 connection

3.5 in (8.9 cm)

1.44 Mbyte or 720 Kbyte MS-DOS compatible

1 Mbyte

1-10 TFP2A FiberMaster Module-Level Service Manual

Operational Characteristics

Table 1-7. Operational Characteristics

Power requirements

AC operation (AC only)

Chapter 1: Introduction

90 - 130 VAC, 47 - 440 Hz 180 - 250 VAC, 47 - 73 Hz

(auto select) AC operation (AC with DC option) DC operation

Power supply rating

AC operation

DC operation

Module capacity

Safety

Physical Characteristics

Table 1-8. Physical Characteristics

90 - 130 VAC, 47 - 73 Hz

11 - 16 VDC

250 watts max.

315 VA max.

200 VA max. (watts)

Two dual-wavelength modules

maximum, for a total of four

wavelengths

UL 1244, UL 3111-1

CSA: CAN/CSA C22.2 No. 231

CAN/CSA -C22.2 No. 1010.192

IEC 1010-1

EN 61010-1

Weight

Dimensions

TFP2A FiberMaster Module-Level Service Manual 1-11

33 lbs (15 kg), mainframe configured with floppydisk drive, internal printer, and one optical module

Overall dimensions, including front cover, handle, and feet: Length, 25 in (63.7 cm); width, 18 in (46 cm); height, 7 in (18 cm)

Chapter 1: Introduction

Environmental Characteristics

Table 1-9. Environmental Characteristics

Temperature

Mainframe

Operating: +5˚ to +50˚ C Non-operating: -40˚ to +60˚ C

With internal printer

Without floppy-disk drive

Humidity (operating)

Mainframe With internal printer Without floppy-disk drive

Altitude (maximum)

Operating Non-operating

Sine vibration

Operating

Disk drive non-operating

Shock (maximum)

Operating

Operating: +5˚ to +40˚ C Non-operating: -20˚ to +60˚ C

Operating: -10˚ to +55˚ C Non-operating: -40˚ to +70˚ C

8% to 75% (+5%, -0%), noncondensing 35% to 75% (+5%, -0%), noncondensing 5% to 90% (+5%, -0%), noncondensing

15,000 ft (4.6 km) 50,000 ft (15.2 km) Tek 062-2847-00, Class 3 (exceeds MIL-T28800E)

Frequency sweep: 10 to 55 Hz Loading: 0.5G, maximum

Frequency sweep: 10 to 55 Hz Loading: 2.0G, maximum

Disk drive non-operating

Bench handling Transit drop Water resistance Fungus resistance

1-12 TFP2A FiberMaster Module-Level Service Manual

30G MIL-T-28800E MIL-T-28800E Drip proof, tested with front cover on Enclosure and electronics are fungus inert by

design

Table 1-9. Environmental Characteristics, cont.

Chapter 1: Introduction

Electromagnetic compatibility

Emissions: Radiated emissions

Mains Current Harmonics Conducted emissions

Magnetic emissions Immunity: RF radiated

Electrostatic discharge Fast transients Surge

Dropout

EC Council Directive 89/336/EEC

EN 50081-1 FCC Part 15, Subpart J, Class A

EN55022, Class B IEC 1000-3-2 FCC Part 15, Subpart J, Class A

EN55022, Class B EN60555-2

Vfg 243, Class B EN 50082-1 IEC 1000-4-3

IEC 1000-4-2 IEC 1000-4-4 IEC 1000-4-5 IEC 1000-4-11

TFP2A FiberMaster Module-Level Service Manual 1-13

Chapter 1: Introduction

FS1300 Singlemode Optical Module

Table 1-10. FS1300 Singlemode Optical Module

Dynamic Range

Dead Zone Pulse End Loss Width SNR = 1 (dB)

Detect. (dB)

Meas. (m)

Event (m)

10 µs/1000 m 29.5 38.0 1080 1050 4000 ns/400 m 27.5 38.0 480 420 2000 ns/200 m 23.5 38.0 240 220 1000 ns/100 m 22.0 38.0 140 110

500 ns/50 m 20.5 38.0 70 55 200 ns/20 m 18.5 38.0 40 25 100 ns/10 m 17.0 38.0 25 12

50 ns/5 m 15.5 38.0 20 7 50 ns/5 m HR 12.0 34.0 15 7 20 ns/2 m HR 10.5 34.0 NA 5 10 ns/1 m HR 9.0 34.0 NA 3

Operating wavelength: 1310 nm ± 20 nm Masking: menu selectable

❏ Auto-QuickMask ❏ Auto-AccuMask ❏ Manual-QuickMask ❏ Manual-AccuMask

Full-screen display range: 50 m to 200 km Laser safety: Class 1, 21 CFR 1040 Temperature: -10˚ to +55˚ C operating; -40˚ to +70˚ C non-operating Humidity: Up to 90% relative humidity (+5, -0%) Weight: 4.4 lbs (<2 kg) Dimensions: 1.75 in (4.5 cm) by 5.5 in (14.0 cm) by 17.5 in (44.5 cm)

Dynamic range specifications are based on 32,000 averages. Actual averaging times range from 30 seconds to three minutes, depending on instrument settings. For 3 Sigma values, subtract 2.4 dB from SNR=1 values.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4% Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter.

Dead zone, event (two-point spatial resolution) is the minimum distance after any reflection necessary to determine accurately the distance to another event (based on a minimum recover of 1.5 dB down from the top of the first reflection).

1-14 TFP2A FiberMaster Module-Level Service Manual

FS1500 Singlemode Optical Module

Table 1-11. FS1500 Singlemode Optical Module

Chapter 1: Introduction

Dynamic Range

Dead Zone Pulse End Loss Width SNR = 1 (dB)

Detect. (dB)

Meas. (m)

Event (m)

10 µs/1000 m 26.5 36.0 1080 1050 4000 ns/400 m 24.5 36.0 480 420 2000 ns/200 m 20.5 36.0 240 220 1000 ns/100 m 19.0 36.0 140 110

500 ns/50 m 17.5 36.0 70 55 200 ns/20 m 15.5 36.0 40 25 100 ns/10 m 14.0 36.0 25 12

50 ns/5 m 12.5 36.0 20 7 50 ns/5 m HR 9.0 33.0 18 7 20 ns/2 m HR 7.5 33.0 NA 5 10 ns/1 m HR 5.0 33.0 NA 3

Operating wavelength: 1550 nm ± 20 nm Masking: menu selectable

❏ Auto-QuickMask ❏ Auto-AccuMask ❏ Manual-QuickMask ❏ Manual-AccuMask

Dynamic range specifications are based on 32,000 averages. Actual averaging times depend on instrument settings. For 3 Sigma values, subtract 2.4 dB from SNR=1 values.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4% Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter.

TFP2A FiberMaster Module-Level Service Manual 1-15

Chapter 1: Introduction

FS1315 Singlemode Optical Module

Table 1-12. FS1315 Singlemode Optical Module

Dynamic Range

Dead Zone

Pulse End Loss

Width SNR = 1 (dB)

Detect. (dB)

Meas. (m)

Event (m)

10 µs/1000 m 29.5/26.5 38.0/36.0 1080 1050 4000 ns/400 m 27.5/24.5 38.0/36.0 480 420 2000 ns/200 m 23.5/20.5 38.0/36.0 240 220 1000 ns/100 m 22.0/19.0 38.0/36.0 140 110

500 ns/50 m 20.5/17.5 38.0/36.0 70 55 200 ns/20 m 18.5/15.5 38.0/36.0 40 25 100 ns/10 m 17.0/14.0 38.0/36.0 25 12

50 ns/5 m 15.5/12.5 38.0/36.0 20 7 50 ns/5 m HR 12.0/9.0 34.0/33.0 15/18 7 20 ns/2 m HR 10.5/7.5 34.0/33.0 NA 5 10 ns/1 m HR 9.0/5.0 34.0/33.0 NA 3

Operating wavelengths: 1310/1550 nm ± 20 nm Masking: menu selectable

❏ Auto-QuickMask ❏ Auto-AccuMask ❏ Manual-QuickMask ❏ Manual-AccuMask

Dynamic range specifications are based on 32,000 averages. Actual averaging times depend on instrument settings. For 3 Sigma values, subtract 2.4 dB from SNR=1 values.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4% Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter.

1-16 TFP2A FiberMaster Module-Level Service Manual

FG1300 Singlemode Optical Module

Table 1-13. FG1300 Singlemode Optical Module

Chapter 1: Introduction

Dynamic Range

Dead Zone Pulse End Loss Width SNR = 1 (dB)

Detect. (dB)

Meas. (m)

Event (m)

10 µs/1000 m 31.0 38.0 1150 1150 4000 ns/400 m 28.5 38.0 550 475 2000 ns/200 m 25.5 38.0 250 225 1000 ns/100 m 24.0 38.0 150 110

500 ns/50 m 21.5 38.0 80 55 200 ns/20 m 19.5 38.0 55 25 100 ns/10 m 18.0 38.0 50 12

50 ns/5 m 16.5 38.0 45 10 50 ns/5 m HR 13.5 34.0 30 7 20 ns/2 m HR 11.5 34.0 25 5 10 ns/1 m HR 9.5 34.0 N/A 4

Operating wavelength: 1310 nm ± 20 nm Masking: not applicable Full-screen display range: 50 m to 200 km Laser safety: Class 1, 21 CFR 1040 Temperature: -10˚ to +55˚ C operating; -30˚ to +70˚ C non-operating Humidity: Up to 90% relative humidity (+5, -0%) Weight: 4.4 lbs (<2 kg) Dimensions: 1.75 in (4.5 cm) by 5.5 in (14.0 cm) by 17.5 in (44.5 cm)

Dynamic range specifications are based on 32,000 averages. Actual averaging

times depend on instrument settings.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated

backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4%

Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter. Specifications are based on reflections not to exceed a return loss of 40 dB.

Performance specifications are at 25˚ C.

TFP2A FiberMaster Module-Level Service Manual 1-17

Chapter 1: Introduction

FG1315 Singlemode Optical Module

Table 1-14. FG1315 Singlemode Optical Module

Dynamic Range

Dead Zone

Pulse End Loss

Width SNR = 1 (dB)

Detect. (dB)

Meas. (m)

Event (m)

10 µs/1000 m 31.0/29.0 38.0/36.0 1150 1150 4000 ns/400 m 28.5/26.5 38.0/36.0 550 475 2000 ns/200 m 25.5/23.5 38.0/36.0 250 225 1000 ns/100 m 24.0/22.0 38.0/36.0 150 110

500 ns/50 m 21.5/19.5 38.0/36.0 80/85 55 200 ns/20 m 19.5/17.5 38.0/36.0 55/60 25 100 ns/10 m 18.0/16.0 38.0/36.0 50/55 12

50 ns/5 m 16.5/14.5 38.0/36.0 45/50 10 50 ns/5 m HR 13.5/11.5 34.0/33.0 30/35 7 20 ns/2 m HR 11.5/9.5 34.0/33.0 25/30 5 10 ns/1 m HR 9.5/7.5 34.0/33.0 N/A 4

Operating wavelengths: 1310/1550 nm ± 20 nm Masking: not applicable Full-screen display range: 50 m to 200 km Laser safety: Class 1, 21 CFR 1040 Temperature: -10˚ to +55˚ C operating; -30˚ to +70˚ C non-operating Humidity: Up to 90% relative humidity (+5, -0%) Weight: 4.4 lbs (<2 kg) Dimensions: 1.75 in (4.5 cm) by 5.5 in (14.0 cm) by 17.5 in (44.5 cm)

Dynamic range specifications are based on 32,000 averages. Actual averaging

times depend on instrument settings.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated

backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4%

Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event on the display to measure loss to within 0.5 dB of backscatter. Specifications are based on reflections not to exceed a return loss of 40 dB.

Performance specifications are at 25˚ C.

1-18 TFP2A FiberMaster Module-Level Service Manual

FL1300 Singlemode Optical Module

Table 1-15. FL1300 Singlemode Optical Module

Chapter 1: Introduction

Dynamic Range

Dead Zone

Pulse End

SNR = 1 (dB)

Detect (dB)

Meas. (m)

Event (m)

20 µs/2000 m 37.5 46.0 2375 2100

10 µs/1000 m 36.0 46.0 1270 1050 4000 ns/400 m 33.5 45.5 670 440 2000 ns/200 m 31.0 44.5 395 220 1000 ns/100 m 29.5 44.5 280 120

500 ns/50 m 27.5 44.0 150 60 200 ns/20 m 25.5 44.0 125 35 100 ns/10 m 24.0 44.0 125 25

Operating wavelength: 1310 nm ± 20 nm Masking: not applicable Full-screen display range: 50 m to 320 km Laser safety: Class 1, 21 CFR 1040 Temperature: -10˚ to +55˚ C operating; -40˚ to +70˚ C non-operating Humidity: Up to 90% relative humidity (+5, -0%) Weight: 4.4 lbs (<2 kg) Dimensions: 1.75 in (4.5 cm) by 5.5 in (14.0 cm) by 17.5 in (44.5 cm)

Dynamic range specifications are based on 262,000 averages. Actual averaging times depend on instrument settings. For 3 Sigma values, subtract 2.4 dB from SNR=1 values.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4% Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter.

TFP2A FiberMaster Module-Level Service Manual 1-19

Chapter 1: Introduction

FL1500 Singlemode Optical Module

Table 1-16. FL1500 Singlemode Optical Module

Dynamic Range

Dead Zone

Pulse End

SNR = 1 (dB)

Detect (dB)

Meas. (m)

Event (m)

20 µs/2000 m 37.0 46.5 2375 2100

10 µs/1000 m 35.0 46.0 1270 1050 4000 ns/400 m 33.0 46.0 670 440 2000 ns/200 m 30.5 45.0 395 220 1000 ns/100 m 29.0 45.0 280 120

500 ns/50 m 27.0 44.5 150 60 200 ns/20 m 25.0 44.5 195 35 100 ns/10 m 23.0 44.0 170 25

Operating wavelength: 1550 nm ± 20 nm Masking: not applicable Full-screen display range: 50 m to 320 km Laser safety: Class 1, 21 CFR 1040 Temperature: -10˚ to +55˚ C operating; -40˚ to +70˚ C non-operating Humidity: Up to 90% relative humidity (+5, -0%) Weight: 4.4 lbs (<2 kg) Dimensions: 1.75 in (4.5 cm) by 5.5 in (14.0 cm) by 17.5 in (44.5 cm)

Dynamic range specifications are based on 262,000 averages. Actual averaging times depend on instrument settings. For 3 Sigma values, subtract 2.4 dB from SNR=1 values.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4% Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter.

1-20 TFP2A FiberMaster Module-Level Service Manual

FL1315 Singlemode Optical Module

Table 1-17. FL1315 Singlemode Optical Module

Chapter 1: Introduction

Dynamic Range

Dead Zone

Pulse End

SNR = 1 (dB)

Detect (dB)

Meas. (m)

Event (m)

20 µs/2000 m 37.5/37.0 46.0/46.5 2375 2100

10 µs/1000 m 36.0/35.0 46.0/46.0 1270 1050 4000 ns/400 m 33.5/33.0 45.5/46.0 670 440 2000 ns/200 m 31.0/30.5 44.5/45.0 395 220 1000 ns/100 m 29.5/29.0 44.5/45.0 280 120

500 ns/50 m 27.5/27.0 44.0/44.5 150 60 200 ns/20 m 25.5/25.0 44.0/44.5 125/195 35 100 ns/10 m 24.0/23.0 44.0/44.0 125/170 25

Operating wavelength: 1310/1550 nm ± 20 nm Masking: not applicable Full-screen display range: 50 m to 320 km Laser safety: Class 1, 21 CFR 1040 Temperature: -10˚ to +55˚ C operating; -40˚ to +70˚ C non-operating Humidity: Up to 90% relative humidity (+5, -0%) Weight: 4.4 lbs (<2 kg) Dimensions: 1.75 in (4.5 cm) by 5.5 in (14.0 cm) by 17.5 in (44.5 cm)

Dynamic range specifications are based on 262,000 averages. Actual averaging times depend on instrument settings. For 3 Sigma values, subtract 2.4 dB from SNR=1 values.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4% Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter.

TFP2A FiberMaster Module-Level Service Manual 1-21

Chapter 1: Introduction

FM8500 Multimode Optical Module

Table 1-18. FM8500 Multimode Optical Module

Dynamic Range

Dead Zone Pulse End Loss Width SNR = 1 (dB)

Detect. (dB)

Meas. (m)

Event (m)

100 ns/10 m 27.0 36.0 13.0 10.5

50 ns/5 m 25.5 36.0 8.5 5.5

20 ns/2 m 23.5 36.0 6.0 3.0 8 ns/80 cm 20.5 36.0 4.5 1.0 3 ns/30 cm 16.5 35.0 3.5 0.5 1 ns/10 cm 14.0 35.0 2.5 0.2

Operating wavelength: 850 nm ± 25 nm Masking: not applicable Full-screen display range: 5 m to 20 km Laser safety: Class 1, 21 CFR 1040 Temperature: 0˚ to +50˚ C operating; -40˚ to +70˚ C non-operating Humidity: Up to 90% relative humidity (+5, -0%) Weight: 4.4 lbs (<2 kg) Dimensions: 1.75 in (4.5 cm) by 5.5 in (14.0 cm) by 17.5 in (44.5 cm)

Dynamic range specifications are based on 32,000 averages. Actual averaging times depend on instrument settings. For 3 Sigma values, subtract 2.4 dB from SNR=1 values.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4% Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter.

1-22 TFP2A FiberMaster Module-Level Service Manual

FM1300 Multimode Optical Module

Table 1-19. FM1300 Multimode Optical Module

Chapter 1: Introduction

Dynamic Range

Dead Zone

Pulse End Loss

Width SNR = 1 (dB)

Detect. (dB)

Meas. (m)

Event (m)

1000 ns/100 m 26.5 38.0 125 110

500 ns/50 m 23.5 38.0 65 55 200 ns/20 m 21.5 38.0 35 25 100 ns/10 m 20.0 38.0 30 12

50 ns/5 m 18.5 38.0 25 7 50 ns/5 m HR 15.0 35.0 20 7 20 ns/2 m HR 13.0 35.0 18 5 10 ns/1 m HR 15.0 35.0 14 3

Operating wavelength: 1300 nm ± 30 nm Masking: not applicable Full-screen display range: 50 m to 100 km Laser safety: Class 1, 21 CFR 1040 Temperature: 0˚ to +50˚ C operating; -40˚ to +70˚ C non-operating Humidity: Up to 90% relative humidity (+5, -0%) Weight: 4.4 lbs (<2 kg) Dimensions: 1.75 in (4.5 cm) by 5.5 in (14.0 cm) by 17.5 in (44.5 cm)

Dynamic range specifications are based on 32,000 averages. Actual averaging times depend on instrument settings. For 3 Sigma values, subtract 2.4 dB from SNR=1 values.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4% Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter.

TFP2A FiberMaster Module-Level Service Manual 1-23

Chapter 1: Introduction

FM8513 Multimode Optical Module

Table 1-20. FM8513 Multimode Optical Module

Dynamic Range

Dead Zone

Pulse End Loss

Width SNR = 1 (dB)

Detect. (dB)

Meas. (m)

Event (m)

850 nm:

100 ns/10 m 27.0 36.0 13.0 10.5

50 ns/5 m 25.5 36.0 8.5 5.5

20 ns/2 m 23.5 36.0 6.0 3.0 8 ns/80 cm 20.5 36.0 4.5 1.0 3 ns/30 cm 16.5 35.0 3.5 0.5 1 ns/10 cm 14.0 35.0 2.5 0.2

1300 nm:

1000 ns/100 m 26.5 38.0 125 110

500 ns/50 m 23.5 38.0 65 55 200 ns/20 m 21.5 38.0 35 25 100 ns/10 m 20.0 38.0 30 12

50 ns/5 m 18.5 38.0 25 7

50 ns/5 m HR 15.0 35.0 20 7 20 ns/2 m HR 13.0 35.0 18 5 10 ns/1 m HR 15.0 35.0 14 3

Operating wavelengths: 850 nm ± 25 nm, 1300 nm ± 30 nm Masking: not applicable Full-screen display range: 850 nm—5 m to 20 km; 1300 nm—50 m to 100 km Laser safety: Class 1, 21 CFR 1040 Temperature: 0˚ to +50˚ C operating; -40˚ to +70˚ C non-operating Humidity: Up to 90% relative humidity (+5, -0%) Weight: 4.4 lbs (<2 kg) Dimensions: 1.75 in (4.5 cm) by 5.5 in (14.0 cm) by 17.5 in (44.5 cm)

Dynamic range specifications are based on 32,000 averages. Actual averaging times depend on instrument settings. For 3 Sigma values, subtract 2.4 dB from SNR=1 values.

Dynamic range, SNR = 1 is the one-way difference between the extrapolated backscatter level at the start of the fiber and the RMS noise level.

Dynamic range, end detection is the one-way difference between the top of a 4% Fresnel reflection at the start of the fiber and the 3 Sigma (99.5%) level of the noise.

Dead zone, loss measurement is the minimum distance after any reflective event

on the display to measure loss to within 0.5 dB of backscatter.

1-24 TFP2A FiberMaster Module-Level Service Manual

Accessories and Options

The following paragraphs list the standard accessories, optional accessories, options,

and option accessories that may be shipped with your FiberMaster OTDR.

Mainframes

Table 1-21. Mainframe Options

Mainframe # Description

TFP2A Mainframe with color monitor TFP2AM Mainframe with monochrome monitor 1T Hard case option 1R 19-inch rackmount option L1 French language option L3 German language option L4 Spanish language option 1S Mainframe with FMTAP

Accessories

Table 1-22. Standard ccessories

Chapter 1: Introduction

Description Part Number Quantity

Power cord, standard 161-0104-00 1 User manual 070-9189-XX 1 Quick-reference card 063-2292-XX 1 Soft case 016-1037-01 1 Front-panel cover 200-3566-00 1 Option-port cover 333-3572-00 1 Plug-in spacer 386-5950-00 1 Rackmount instruction sheet 063-1691-XX

Table 1-23. Optional Accessories

Nomenclature Part or Option Number

Jumpers (all combinations) Keyboard adapter cable 174-2356-01 External plotter HC100 or HC100 Option 03 RS232C cable 012-1384-00 GPIB cable (2 meter) 012-0991-00 Hard-shell transit case 016-1036-00 Module-level service manual 070-9188-XX FiberMaster Trace Analysis Pkg. FMTAP FiberMaster utilities disk 063-1493-XX Keyboard 118-7637-00 TOP130 LED source 850/1300 nm w/ ST connector 2T TOP140 laser source 1550 nm w/ FC connector 3T

TFP2A FiberMaster Module-Level Service Manual 1-25

Chapter 1: Introduction

Options

Table 1-24. Optional Accessories (Con’t)

Nomenclature Part or Option Number

TOP150 laser source 1550 nm w/ FC connector 4T TOP200 optical power meter 850/1300/1550 nm w/ ST connector 5T TOP300 visual fault finder 635 nm w/ FC connector 6T TOP160 laser source 1310/1550 nm w/ FC connector 7T French User Manual 070-9428-XX German User Manual 070-9429-XX Spanish User Manual 070-9430-XX French Quick Reference Card 063-1844-XX German Quick Reference Card 063-1982-XX Spanish Quick Reference Card 063-1983-XX

Table 1-25. System Options

Opt. # Description

14 1 Mbyte nonvolatile RAM 16 Internal printer assembly 17 DC power option 19 Keyboard and adapter cable (USA format) A1 Universal European, 220VAC/16A, 50 Hz A2 United Kingdom, UK, 240VAC/13A, 50 Hz A3 Australian, 240VAC/10A, 50 Hz A4 North American, 240VAC/12A, 60 Hz A5 Swiss, 250VAC/6A, 50Hz

Table 1-26. System Multimode Options

Opt. # Description Order #

01 850 nm MM acquisition module FM8500* 02 1300 nm MM acquisition module FM1300* 03 850/1300 nm MM acquisition module FM8513* 20 Biconic connector, MM, 62.5 µm 119-4515-00 21 FC/PC connector, MM, 62.5 µm 119-4516-00 22 D4/PC connector, MM, 62.5 µm 119-4514-00 23 SMA 905/906 connector, MM, 62.5 µm 119-4557-00 24 ST/PC connector, MM, 62.5 µm 119-4513-00 25 DIN/PC 47256 connector, MM, 62.5 µm 119-4546-00 26 Diamond 3.5 connector, MM, 62.5 µm 119-4558-00 27 Diamond 2.5 connector, MM, 62.5 µm 119-4556-00 28 SC/PC connector, MM, 62.5 µm 119-4518-00 29 SMA 2.5 connector, MM, 62.5 µm 119-4517-00

*Use when ordering optical module for a previously purchased mainframe, and when ordering connector options for a previously purchased optical module.

1-26 TFP2A FiberMaster Module-Level Service Manual

Chapter 1: Introduction

Table 1-27. System Singlemode Options

Opt. # Description Order #

04 1310 nm SM acquisition module FS1300* 05 1550 nm SM acquisition module FS1500* 06 1310/1550 SM acquisition module FS1315* 07 1310 nm SM long-range acquisition module FL1300* 08 1310/1550 nm SM long-range acquisition module FL1315* 09 1550 nm SM long-range acquisition module FL1500* 10 1310 nm SM general-purpose acquisition module FG1300* 11 1310/1550 SM general-purpose acquisition module FG1315* 30 Biconic connector, SM 119-4515-00 31 FC/PC connector, SM 119-4516-00 32 D4/PC connector, SM 119-4514-00 33 SMA 905/906 connector, SM 119-4557-00 34 ST/PC connector, SM 119-4513-00 35 DIN/PC 47256 connector, SM 119-4546-00 36 Diamond 3.5 connector, SM 119-4558-00 37 Diamond 2.5 connector, SM 119-4556-00 38 SC connector, SM 119-4518-00 39 SMA 2.5 connector, SM 119-4517-00 41 FC/APC connector, SM** 119-5115-00 42 SC/APC connector, SM** 119-5116-00

*Use when ordering optical module for a previously purchased mainframe, and when ordering connector options for a previously purchased optical module. ** Angle polish connectors (options 41 and 42) cannot be interchanged with any of the option 2x or 3x adapters.

Table 1-28. Option Accessories

Description Part Number Quantity

Thermal print paper 006-7682-00 1 Thermal print paper, case 006-7682-20 50 Paper holders 386-5947-01 2 3-1/2" diskette, 1.44 MB 119-3910-00 1

Power cord, option A1 161-0104-06 1 Power cord, option A2 161-0104-07 1 Power cord, option A3 161-0104-05 1 Power cord, option A4 161-0134-00 1 Power cord, option A5 161-0167-00 1 Power cord, option 17 161-0280-01 1

TFP2A FiberMaster Module-Level Service Manual 1-27

Chapter 1: Introduction

Opt. 20 Multimode Opt. 30 Singlemode

Opt. 21 Multimode Opt. 31 Singlemode Opt. 41 Singlemode

Opt. 22 Multimode

Opt. 32 Singlemode

Opt. 25 Multimode Opt. 35 Singlemode

Opt. 26 Multimode Opt. 36 Singlemode

Opt. 27 Multimode Opt. 37 Singlemode

Opt. 23 Multimode Opt. 33 Singlemode

Opt. 24 Multimode Opt. 34 Singlemode

Figure 1-1. Connector Options

Opt. 28 Multimode Opt. 38 Singlemode Opt. 42 Singlemode

Opt. 29 Multimode Opt. 39 Singlemode

1-28 TFP2A FiberMaster Module-Level Service Manual

Unpacking and Preparation for Use

Before unpacking FiberMaster from its shipping container or carton, inspect for signs

of external damage. If the carton is damaged, notify the carrier. The shipping carton contains the instrument and its standard and optional accessories.

If the contents of the shipping container are incomplete, if there is mechanical

damage or defects, or if the instrument does not meet operational check requirements, contact your local Tektronix Field Office or representative. If the shipping container is damaged, notify the carrier as well as Tektronix.

The instrument was inspected both mechanically and electrically before shipment. It

should be free of mechanical damage and meet or exceed all electrical specifications. Functional and operational self tests are performed at power-on. If your instrument fails to perform satisfactorily, contact your Tektronix representative immediately, or in the U.S. and Canada, telephone toll free 1-800-835-9433.

Preparation for Use

Use FiberMaster’s front cover to protect the front panel when storing and transporting

the instrument. Remove the cover by pulling out on the sides and lifting off. Replace the cover by pressing it over the front panel until the cover snaps in place. The instrument’s accessories are stored in the soft carrying case.

Chapter 1: Introduction

You can position FiberMaster’s handle to serve as a tilt stand, or you can move it to

the front of the instrument, so the instrument can be stacked or carried. To position the handle, press in at both pivot points and rotate to the desired position.

Power Source and Power Requirements

FiberMaster is intended to be operated from a power source that does not apply more

than 250V RMS between the supply conductors, or between either supply conductor and ground. A protective ground connection by way of the grounding conductor in the power cord is essential for safe operation.

The AC power connector is a three-wide, polarized plug with the ground (earth) lead

connected directly to the instrument frame to provide electrical shock protection. If the unit is connected to any other power source, the unit frame must be connected to an earth ground.

CAUTION

To avoid electric shock, the power cord protective grounding conductor must be connected to ground.

TFP2A FiberMaster Module-Level Service Manual 1-29

Chapter 1: Introduction

Power and voltage requirements are printed on the back panel. With the DC power

option (option 17), FiberMaster can be operated from 11 to 16 VDC, or from 90 to 250 VAC nominal line voltage at 47 to 73 Hz. AC-only instruments can be operated from 90 to 250 VAC, 47 to 73 Hz; or from 90 to 130 VAC, 47 to 440 Hz. In AC-only instruments, power source selection is made automatically when the unit is plugged in.

Installing the Optical Module(s)

Your TFP2A mainframe may be shipped with optical module(s) installed. If you order

modules separately, you may have to install them at your site. Install one or two optical modules into the mainframe as follows:

1. Detach the left-hand side of the mainframe back panel by unscrewing four black

quick-release screws in each corner of the back-panel assembly (see figure 1-2). Pull the back-panel assembly off the mainframe using the handle provided, disconnecting the control and module support boards from the interconnect board, which is attached to the inside of the back panel.

2. Plug one module into the bottom set of module connectors on the interconnect

board, inserting the module’s screwholes through the back-panel assembly. (See figure 1-3.)

Figure 1-2. Installing Optical Modules

1-30 TFP2A FiberMaster Module-Level Service Manual

Chapter 1: Introduction

3. Secure the module to the back-panel assembly by tightening the two back-panel

quick-release screws into the module’s screwholes.

4. If you have a second module, plug it into the top set of module connectors on the

interconnect board.

Module support

board connectors

Module connectors

(use for second module)

INTERCONNECT

Module connectors

(use for single module)

Control board

connector

Figure 1-3. Interconnect Circuit Board Connectors

5. Secure the second module to the back-panel assembly by tightening the two quick-

release screws into the module’s screwholes.

TFP2A FiberMaster Module-Level Service Manual 1-31

Chapter 1: Introduction

6. If you are installing two modules, snap the plastic spacer between the modules as

shown in figure 1-4, into the holes provided.

NOTE

Figure 1-4. Installing the Module Spacer:

Two-Module Configuration

7. Place the modules inside the mainframe, lining up the fiber connectors with the

openings in the front panel, and reconnecting the control and module support boards to the interconnect board.

Align the connectors on the interconnect board correctly to ensure complete connections with the module support board, optical module(s), and control board. If connections are not made properly, the instrument will not work.

8. Reattach the back-panel assembly to the mainframe by tightening the four black

quick-release screws. All the screws in the back-panel assembly can be tightened further using a screwdriver, if necessary.

To take the modules out of the TFP2A mainframe, reverse this procedure.

1-32 TFP2A FiberMaster Module-Level Service Manual

Front-Panel Covers

If your instrument includes one optical module, the top module slot on the front panel

is unused. If your instrument is not configured with a floppy-disk drive, the drive slot is unused. Unused option slots are covered before the instrument is shipped from the factory. If you change your instrument’s configuration, however, you may need to remove or install these covers, as shown in figure 1-5.

Option-port cover

Chapter 1: Introduction

Disk-drive cover

Figure 1-5. Front-Panel Option Covers

TFP2A FiberMaster Module-Level Service Manual 1-33

Chapter 1: Introduction

Loading Paper into the Internal Printer

To load paper into the internal thermal printer, follow these steps:

1. Slide the printer cover back.

2. Lift out the old paper roll and remove the black disks from either end.

3. Insert the disks into the ends of the new paper roll.

4. Place the new roll into the printer, with the end of the paper coming out from under

the roll towards the front of the instrument.

5. Push the paper tension lever down, and hold it down for step 6.

6. Feed the paper into the slot in the paper guide, until it comes out in front of the

aluminum paper guide. See figure 1-6. The arrows indicate the direction in which to feed the paper.

7. Release the tension lever.

When the printer is in use, slide the printer cover closed until it reaches the stops

provided for the paper opening. Use the serrated edge of the cover as a guide to tear the paper off. After printing, tear off any remaining paper and slide the cover completely closed over the printer.

Paper tension lever

Figure 1-6. Loading Paper into the Internal Printer

1-34 TFP2A FiberMaster Module-Level Service Manual

Laser Output

Chapter 1: Introduction

FiberMaster is equipped with low-energy lasers and does not output continuous laser

light unless you have started data acquisition by pressing the START/STOP button. The LED next to the currently selected laser source flickers to indicate the laser is firing.

WARNING

The TFP2A FiberMaster has been classified as a Class 1 laser product under the Radiation Control and Health Safety Act of 1968.

Although output from a Class 1 laser is not considered hazardous, it is good practice not to allow eye exposure from direct or reflected laser light. This can be avoided by covering the end of the fiber or directing the output at a non-reflective surface.

It is important to set up and operate the instrument as instructed in this manual. Use of controls or adjustments for performance of procedures other than those specified herein may result in hazardous radiation exposure.

Storage

Both short-term and long-term storage conditions must meet the enviromental

specifications given for the FiberMaster earlier in this chapter.

Repacking for Shipment

When packing an instrument for shipping to a Tektronix Service Center for service or

repair, attach a tag showing the name and address of the owner, name of the individual at your firm to contact, complete serial number, and a description of the service required. If the original packaging is not available, repackage the instrument as follows:

1. Install the front cover on the OTDR.

2. Position the handle over the front cover, and wrap the instrument in polyethylene

sheeting to protect the finish.

3. Cushion the instrument on all sides with packing material or urethane foam

between the carton and the sides of the instrument.

4. Seal the carton using shipping tape.

No special handling is required to prepare the floppy-disk drive for shipping. A shipping carton and packing material can be obtained through your local Tektronix

field office or representative, if necessary.

If you have any questions, contact your local Tektronix field office or representative or

in the U.S. and Canada call toll free 1-800-835-9433.

TFP2A FiberMaster Module-Level Service Manual 1-35

Chapter 1: Introduction

Recalibration

Tektronix recommends that the TFP2A be sent to the factory or a qualified Tektronix

service center for recalibration every 12 months. To arrange for recalibration, contact any Tektronix service center or call 1-800-835-9433.

1-36 TFP2A FiberMaster Module-Level Service Manual

2 General Operating

Instructions

Before servicing FiberMaster, read the following operating instructions. These

instructions are at the level appropriate for servicing the OTDR. Refer to the

FiberMaster User Manual

Additional instructions are integrated into the service procedures given in following

chapters. For example, the procedure in the Performance Check and Adjustment section contain instructions for making the front-panel settings required to check each instrument characteristic included there. Also, the instructions for operating FiberMaster’s internal diagnostic routines are given in chapter 5, may also find the product description in chapter 1 useful for understanding how the instrument functions.

for complete operating instructions.

Maintenance

. You

TFP2A FiberMaster Module-Level Service Manual 2-1

Chapter 2: General Operating Instructions

Overview of FiberMaster Operation

Start data acquisition on a fiber-optic cable under test by simply connecting the cable

to the appropriate front-panel connector, and pressing the START/STOP button. An averaged waveform appears on the screen, and you can make measurements immediately.

The FiberMaster OTDR provides five measurement modes for viewing faults and

measuring transmission loss, fusion-splice loss, connection loss, return loss, and other characteristics of fiber-optic cable. These are Preview, Two Point, Splice Loss, and two Return Loss modes.

❏ Preview mode gives a clear overview of the fiber. Scan fiber features and

measure distances in Preview mode.

❏ Two Point mode allows you to measure loss between any two points on the fiber. ❏ Splice Loss mode gives loss measurements at splice points along the fiber. ❏ Link Return Loss mode lets you measure the return loss of a fiber link. ❏ Event Return Loss shows the return loss for a particular event on the fiber.

Enter each measurement mode by pressing a front-panel softkey. Two-point, splice-

loss, and return-loss measurements can be made automatically. Front-panel controls permit manual adjustment to automatic measurements.

Automatic and manual event-marking modes locate and perform measurements on

all events on the fiber under test. An online table is compiled that contains two-point, splice-loss, return-loss, and distance measurements for each event. You can adjust measurement values on the table, and enter and edit notes for each event.

A general-purpose interface bus (GPIB) and the RS-232 serial interface allow remote

control of the instrument.

Advanced Functions

FiberMaster’s automatic measurements provide adequate data for many applications.

If you require more in-depth fiber analysis, however, the instrument’s advanced functions offer extended flexibility in acquiring and interpreting fiber data. These functions include:

❏ High-density data acquisition ❏ A dual-waveform display, for comparing two waveforms ❏ Manipulation of the expansion window ❏ Real-time acquisition ❏ Manual-masking capabilities

2-2 TFP2A FiberMaster Module-Level Service Manual

Instrument Configuration

Instrument configuration and measurement settings are set through a menu system,

accessed by pressing a front-panel softkey. You can set parameters using various front-panel controls to enter the data, or you can connect an optional IBM-ATcompatible keyboard to FiberMaster for data entry.

Mass Storage

The mass-storage system is also entered through a front-panel softkey, for storing

waveform and settings data on floppy disks or an optional internal RAM. Data is saved in MS-DOS-compatible files.

Chapter 2: General Operating Instructions

TFP2A FiberMaster Module-Level Service Manual 2-3

Chapter 2: General Operating Instructions

The Acquisition Screen

The acquisition screen displays fiber test data and measurement information, and is

used for all fiber-evaluation activity. Other than instrument setup, event marking, and mass-storage operations, most of your work with FiberMaster will be on the acquisition screen.

The acquisition screen displays either data acquisition in progress or a completed

acquisition, including all measurements on the fiber under test. Distance and loss cursors display on this screen, depending on the measurement mode, and can be manipulated to perform manual measurements on the fiber.

The acquisition screen includes:

❏ A horizontal distance scale and a vertical loss scale. ❏ One or two distance cursors, and one or two loss cursors, depending on the

measurement mode.

Vertical scale (dB)

Inactive distance cursor

Waveform settings

Expansion window

Active distance cursor

Softkey labels

Loss cursors

Horizontal scale (kilometers or kilofeet)

(current measurement mode is highlighted)

Figure 2-1. Features on the Acquisition Screen

2-4 TFP2A FiberMaster Module-Level Service Manual

Chapter 2: General Operating Instructions

❏ An expansion window. Pressing the EXPAND button on the front panel switches

between expanded view and overview. In expanded view, the area within the expansion window is magnified to fill the display, allowing closer examination of the fiber. See figure 2-2.

Figure 2-2. Acquisition Screen Expansion—Overview (top),

and Expanded View (bottom)

TFP2A FiberMaster Module-Level Service Manual 2-5

Chapter 2: General Operating Instructions

❏ Waveform and measurement data. Distance and loss measurements are

displayed on the screen near the waveform. In Two Point mode and both returnloss modes, the slope calculation and return loss, respectively, appears in the upper right-hand corner of the screen. The message User Adjusted Measurement displays in the upper left-hand corner of the screen for all manually adjusted measurements. The actual number of averages that were performed on the waveform, and the actual elapsed averaging time are shown in the upper center screen. If an acquisition is in progress, the number of averages and the time elapsed are seen increasing.

During an acquisition, the display also contains an acquisition-active indicator in the lower-left corner of the waveform area. This indicator provides a quick way to check whether an acquisition is still in progress. When data acquisition is complete, and calculations are still in progress, the indicator changes to show a clock with a swinging pendulum.

When event-marking mode is turned on, events on the fiber are marked and numbered at the bottom of the acquisition screen. In addition, when the active distance cursor is on an event marker, a field below the horizontal distance scale displays measurements for that event.

❏ On color monitors, the waveform area of the acquisition screen is color coded for

easier interpretation of data and measurements. Waveform data, including the active waveform (except for high-density data), the number of averages, elapsed time, and the Normal Density or High Density message, is green. The useradjustable elements—distance and loss cursors, and the User Adjusted Measurement message—are displayed in red. Measurement values such as the two-point distance and loss, splice loss, fiber loss, and return loss figures are shown in yellow. Event markers are also displayed in yellow.

2-6 TFP2A FiberMaster Module-Level Service Manual

Chapter 2: General Operating Instructions

❏ All waveform settings used for the acquisition are displayed at the bottom of the

screen. These user-defined settings are selected on the Waveform Settings menu, reached by pressing the Change Settings softkey on the acquisition screen. Refer to the

FiberMaster User Manual

, for details on configuring your

instrument and setting parameters. A Module parameter in the list of settings indicates which laser source is

currently selected. The type of module is shown, plus the currently selected wavelength. For example, FS1315-1310SM indicates that the 1310-nm wavelength of a dual-wavelength singlemode FS-type optical module is currently selected. If the active module is different from the one that was used to acquire the current waveform, the module parameter is highlighted.

The module parameter may include alphabetical characters to indicate the modification level of the module, and whether the module has an internal fiber with a non-standard core diameter. This information is appended to the wavelength. Lower-case letters indicate the modification level of the module, and upper-case letters stand for a non-standard core diameter. For example:

FS1315-1310SM — standard module with standard core diameter FS1315-1310SMaA — modified module with non-standard core diameter FS1315-1310SMA — standard module with non-standard core diameter FS1315-1310SMa — modified module with standard core diameter

For more information on module modifications and internal fiber core diameters, in the U.S. and Canada, call 1-800-835-9433, or contact your local Tektronix representative.

The Source parameter shows where the current waveform data originated. The data could be the result of an acquisition, a data transfer, or from a mass-storage file. For an acquisition, the parameter displays as Source = Acquisition. If the waveform was loaded from mass storage, the parameter reads File =

<FILE_NAME> where <FILE_NAME> is the name of the mass-storage file. If the

waveform data was received via an XModem data transfer, the parameter reads Source = XModem.

❏ Softkey labels display along the right-hand edge of the screen. On the acquisition

screen, the softkeys allow you to switch measurement modes, view the event table, enter the menu system, and access mass-storage functions.

TFP2A FiberMaster Module-Level Service Manual 2-7

Chapter 2: General Operating Instructions

Basic Operating Procedures

Cursor controls Optical module(s)

TFP2 FiberMaster

POWER

Mass storage Display Softkeys

ON OFF

Figure 2-3. Front Panel Overview

HARD COPY

HELP

SELECT

Window controls

WFM

CURSOR

SELECT

LOSS

WINDOW EXPAND

SIZE

WAVEFORM

POSITION

CURRENT

REFERENCE

STORE

MODULE

SELECT

REMOTE

START/

STOP

HOLD FOR REAL TIME

KEYBOARD

Waveform controls

2-8 TFP2A FiberMaster Module-Level Service Manual

Chapter 2: General Operating Instructions

DC power (option 17) AC power

CAUTION

TURN POWER OFF WHEN

REMOVING MODULE PANEL

SINGLE

POSITION

Listed

RS232 GPIB

Figure 2-4. Back Panel

CAUTION

90–250V AC, 47–73 Hz

10 – 32 VDC

200 VA MAX

CAUTION

RS232

GPIB

Power on

POWER

To turn on FiberMaster and start the power-on sequence of self tests, press the

POWER button. Pressing the POWER button a second time turns off the instrument.

To quick-start the instrument, push the POWER button while holding down the START/

STOP button. Release the START/STOP button after you see the message Starting

operating system... on the instrument screen. Quick-start makes the instrument

bypass the power-on diagnostics, causing the start-up screen to appear faster.

Do not quick-start your instrument every time it is powered on. Allow the instrument to

run the power-on diagnostics periodically to detect any malfunctions that might have occurred.

TFP2A FiberMaster Module-Level Service Manual 2-9

Chapter 2: General Operating Instructions

Read help

HELP

Push the HELP button to read help information on the current operation. For example,

if the instrument is in Splice Loss mode, pressing the HELP button lets you read explanations on splice-loss measurement and the functions of the front-panel controls in Splice Loss mode. In the menu system, pressing the HELP button displays information about the currently selected setting.

Select a wavelength

MODULE

SELECT

Push the MODULE SELECT button to cycle through the available laser sources. The

corresponding indicator next to each module lights up to show which wavelength is currently selected. After making your selection, press START/STOP to start a new acquisition using the selected wavelength.

The module parameter in the list of settings at the bottom of the acquisition screen shows which laser source is selected. The type of module is shown, plus the current wavelength. For example, FS1315-1310SM indicates that the 1310-nm wavelength of a dual-wavelength singlemode FS-type optical module is currently selected. If the active module is different from the one used to acquire the current waveform, the module parameter is highlighted until you start a new acquisition.

Set up the system

Change Settings

Enter the menu system by pressing the Change Settings softkey. Using the menus,

you can select waveform, operator, and system settings, set user power-on defaults, and perform remote data transfers. Refer to the on selecting instrument settings.

Start an acquisition

START/

STOP

Press the START/STOP button once to start an averaged waveform acquisition based

on the current instrument settings. Pressing START/STOP again before an averaged acquisition is complete stops the acquisition.

Pressing and holding the START/STOP button starts a real-time acquisition, useful for

adjusting fiber connections and making splices. In real-time mode, data is averaged minimally, and new acquisitions are displayed continually. To stop a real-time acquisition, press START/STOP again.

FiberMaster User Manual

for details

2-10 TFP2A FiberMaster Module-Level Service Manual

Move the distance cursor

CURSOR

Turn the CURSOR knob to move the active distance cursor along the waveform. The

distance from the instrument’s front panel to the cursor position is displayed at the top of the cursor. In the menu system, use the CURSOR knob to select instrument parameter settings.

Expand the view

EXPAND

Press the EXPAND button to switch between overview and expanded view. The

degree of expansion is controlled by the size of the expansion window.

Chapter 2: General Operating Instructions

Size the expansion window

SIZE

Change the size of the expansion window using the vertical and horizontal SIZE

knobs. In expanded view, these controls expand and contract the waveform itself, instead of the expansion window.

Switch active cursors

CURSOR

SELECT

In Preview, Two Point, and Link Return Loss modes, which have two distance

cursors, press the CURSOR SELECT button to pick which distance cursor is controlled by the CURSOR knob. In Splice Loss and Event Return Loss modes, which have one distance cursor and two loss cursors, press CURSOR SELECT to pick which loss cursor is controlled by the LOSS knobs.

The active cursors are shown at higher intensity to differentiate them from the

inactive cursors.

Join cursors: Press and hold the CURSOR SELECT button to join cursors. In Preview,

Two Point, and Link Return Loss modes, the inactive distance cursor is moved to the same location as the active cursor. In Splice Loss and Event Return Loss modes, the inactive loss cursor is moved to the same amplitude and slope as the active cursor.

TFP2A FiberMaster Module-Level Service Manual 2-11

Chapter 2: General Operating Instructions

Adjust loss cursors

LOSS

Use the LOSS knobs to make manual adjustments to automatic measurements in Two

Point, Splice Loss, Link Return Loss, and Event Return Loss modes. The vertical

LOSS knob moves the active loss cursor up and down. The slope LOSS knob rotates

the active loss cursor around the point where it intersects the distance cursor.

Move the waveform

WAVEFORM

POSITION

Move the active waveform up and down and from side to side on the display using

the vertical and horizontal POSITION knobs.

Select a waveform

WFM

SELECT

Pressing the WFM SELECT button alternately selects the current and the reference

waveform as the active waveform. One of the indicators next to the WFM SELECT button lights to show which waveform is active.

When dual-trace mode is on, both the current and reference waveforms are

displayed, with the active waveform at higher intensity. When dual trace is not on, only the active waveform is displayed. (Turn on dual-trace mode through the menu system.)

Press and hold the WFM SELECT button to zero the waveform’s position. It is moved so

that the amplitude and distance axes meet at 0 dB and 0 km. In dual-trace mode, pressing and holding WFM SELECT moves the inactive waveform to the same dB scale as the active waveform.

Store a waveform

STORE

Press the STORE button to store the current waveform and associated settings into

reference memory. The previous contents of reference memory are overwritten.

2-12 TFP2A FiberMaster Module-Level Service Manual

Event Table

Event

Table

Two-Point Mode

Chapter 2: General Operating Instructions

Press this softkey to display the Event Table screen. The event table shows distance

and loss measurements for events marked on the fiber. The Event Table screen allows access to additional screens where you can read and enter notes and mapping information about each event.

On the acquisition screen, pressing and holding the Event Table softkey for two

seconds turns event markers on and off.

You can set FiberMaster to locate and mark events automatically or you can mark

events manually. The Event Marking parameter on the Waveform Settings menu (accessible from the acquisition screen by pressing Change Settings) lets you choose automatic or manual event marking, and gives access to an additional screen for placing markers manually.

Two

Point

Press this softkey to enter Two Point mode. Use Two Point mode to make

measurements between two points on a fiber, including end-to-end distance and loss measurements and fiber-loss measurements. Two distance and two loss cursors define two-point measurements. Loss between the two distance cursor positions is calculated and displayed in the upper-right corner of the screen.

To turn off Two Point mode and enter Preview mode, press and hold the Two Point

softkey.

This softkey is available only when return loss is off.

Splice Loss Mode

Splice

Loss

Press this softkey to enter Splice Loss mode. Use Splice Loss mode to measure loss

caused by a particular fiber feature, for example a connector or splice. There are one distance cursor and two loss cursors in Splice Loss mode. The loss at the distance cursor is calculated and displayed.

To turn off Splice Loss mode and enter Preview mode, press and hold the Splice

Loss softkey.

This softkey is available only when return loss is off.

TFP2A FiberMaster Module-Level Service Manual 2-13

Chapter 2: General Operating Instructions

Return Loss/Exit Return Loss

Return

Loss

Exit

Return

Loss

Use these softkeys to turn the return-loss measurement modes on and off. When

return loss is on, the Two Point softkey is replaced by the Link Return Loss softkey, the Splice Loss softkey is replaced by the Event Return Loss softkey, and Return

Loss changes to Exit Return Loss. When return loss is off, the softkeys revert to Two Point, Splice Loss, and Return Loss.

Link Return Loss

Link

Return

Loss

Press this softkey to enter Link Return Loss mode. Use Link Return Loss mode to

measure the transmission energy lost due to the total light reflected by a link. Two distance cursors are used to define the link to be measured, and one loss cursor establishes the backscatter level before the link. Link return loss between the two distance cursor positions is calculated and displayed in the upper-right corner of the screen.

To turn off Link Return Loss mode and enter Preview mode, press and hold the Link

Return Loss softkey.

This softkey is available only when return loss is on.

Event Return Loss

Event

Return

Loss

Press this softkey to enter Event Return Loss mode. Use Event Return Loss mode to

measure the transmission energy lost due to the total light reflected by a particular reflective fiber feature, such as a connector or splice. A single distance cursor is used to indicate the reflection to be measured. One loss cursor establishes the backscatter level before the event, and a second loss cursor marks the top of the reflection. Event return loss is calculated and displayed in the upper-right corner of the screen.

To turn off Event Return Loss mode and enter Preview mode, press and hold the

Event Return Loss softkey.

This softkey is available only when return loss is on.

2-14 TFP2A FiberMaster Module-Level Service Manual

Print

HARD

COPY

Mass Storage

Mass

Storage

Chapter 2: General Operating Instructions

Print a hard copy of the screen. If an external plotter is selected as the hardcopy

device, only the acquisition screen can be hard copied. The internal printer or any external printer can print hard copies of menus, help screens, and event tables as well.

Enter the mass-storage menu system by pressing the Mass Storage softkey. Use

this system to load waveform and settings data from mass storage to the instrument, save data from the instrument to mass storage, format mass-storage media, and delete and copy files.

TFP2A FiberMaster Module-Level Service Manual 2-15

Chapter 2: General Operating Instructions

2-16 TFP2A FiberMaster Module-Level Service Manual

3 Theory of Operation

A1 - Control

Host Processor

The host processor has a 68020 microprocessor core, which contains the 68020,

system ROM, system RAM, and interfaces for the display processor and peripherals. The host processor has direct control over the mass-storage, hardcopy, external I/O, front-panel, and acquisition systems. Indirect control is exercised over the display system, a secondary processor that performs the required data manipulation under the host processor’s control.

The host processor has three main functions:

1. Instrument Control. At power-on, control software from each plug-in optical

module is uploaded to the host processor. Instrument operation is controlled by this software and the operating-system kernel resident in the mainframe. Front-panel controls are monitored, and information from the panel is used by the host processor.

Instrument control also includes control of the mass-storage device(s), the hardcopy device, and external communications.

2. Data Acquisition. The host processor computes the data-acquisition parameters

for the timebase and the signal averager from the current instrument state and loads the command data into the front end. Masking requirements and plug-in setup are sent to the selected optical plug-in module and module support.

3. Data Manipulation. Data is accumulated in the signal-averager memory. The host

processor converts raw measurement data to data that is meaningful to the user.

Display Processor

The display processor has a 34010 graphics processor core that contains the 34010

microprocessor, ROM, RAM, video frame buffer and interfaces to the host processor system and video display.The display processor has two main functions:

1. Waveform Post-Processing. Corrected waveform data and front-panel switch

settings are received by the display processor from the host processor. Waveform data is scaled and formatted to reflect the front-panel switch settings. The newly formatted waveform and its associated measurement text are then placed into the frame buffer to be displayed on the video display.

TFP2A FiberMaster Module-Level Service Manual 3-1

Chapter 3: Theory of Operation

2. Automatic Display Refresh. The display processor generates the

synchronization and blanking signals required to drive the video display and liquidcrystal shutter. The display processor is programmed to support a 640-by-480 screen resolution in a non-interlaced video mode.

Timebase

The data-acquisition system uses a combination of high-speed (10 Msamples/sec) and

sequential sampling techniques. The timebase provides the signals necessary to control the acquisition. The timebase consists of a sampler control/address generator and a pulse generator.

The sampler control/address generator controls sample density, time positioning of the

data acquisition window relative to the pulse, and the averaging system.

The pulse generator produces the triggers that control the laser pulse generators in the

optical modules. In those applications using optical masking, the pulse generator allows time positioning of the mask relative to the pulse.

Signal Averager

The signal averager and its primary memory constitute the core of the high-speed

digital data-acquisition system. The signal averager is controlled by the sampler control/address generator to maintain a 10Msample/second throughput as it accumulates and averages input data. The averager receives its input directly from the optical plug-in modules on the HSD bus.

Once the acquisition cycle has concluded, the memory performs a DMA dump to the

signal-averager buffer memory where the host processor may access it as desired. This transfer, like the acquisition, is controlled by the sampler control/address generator in both control signals and addressing.

3-2 TFP2A FiberMaster Module-Level Sevice Manual

A2 - Front Panel

Front Panel

The front panel provides the interface between the host processor and the operator.

This human interface consists of the following:

• Seven quadrature shaft encoders

• Fourteen push-buttons and softkeys

• Four LEDs

• IBM-AT-compatible keyboard interface All front-panel control logic has been incorporated into a single front-panel controller.

A3 - Power Supply

Instrument power is provided by a switching type power supply. The power supply has

an auto-ranging input system that allows it to function on both 110 VAC and 220 VAC. A DC option allows operation from 11 to 16 VDC.

Chapter 3: Theory of Operation

A4 - Interconnect

Interconnect

The interconnect board connects the control board with the two plug-ins and the

optical-module support board. The interconnect board provides power and control for operating the plug-ins, as well as for handling the digital data flow from the front end.

TFP2A FiberMaster Module-Level Service Manual 3-3

Chapter 3: Theory of Operation

A5 - Module Support

Digital Interface and Cooler Power Supplies

The backplane interface connections are made through the two edge-card connectors

that contain four basic areas of connections: cooler sense and power, sample-strobe signals, CPU bus signals, and mask-control signals.

Up to four lasers may be controlled by the laser-cooler power supply. Each of the lasers

is packaged with a thermoelectric cooler and a 10KΩ thermistor. The lasers are stabilized at a temperature between 15 and 35 degrees Celsius, determined during the plug-in calibration. The temperature is selected to optimize power and wavelength.

The detector cooler power supplies are a simplified version of the laser cooler power

supplies. All detectors are set to operate at -10 degrees Celsius. Up to two detector thermoelectric coolers can be controlled by the detector cooler power supplies.

Mask Generator

The mask generator converts parallel mask pattern bits provided by the mask RAM into

a serial bit pattern to drive the optical masking circuitry. Timing control for this operation is driven by a 160MHz clock, which is derived from a 40MHz clock. This 40MHz clock is synchronous with the pulse system.

Strobe Continuation

In order to minimize the transients caused by starting and stopping the sampling

system, dummy fill strobes are generated and supplied to the sampler when no data is to be taken. A shift register is used to produce the fill strobe with the proper timing relationship. This register is clocked by a 40MHz signal that is synchronous with the sampling system.

3-4 TFP2A FiberMaster Module-Level Sevice Manual

A6 - Printer Assembly

Printer-Power Distribution

The printer-power distribution board is used for cable management and +24V power-

supply control.

A7 - Display Assembly

Display

The display is a 7-inch-diagonal, 480-line-by-640-pixel raster CRT display monitor. To

obtain a three-color system, a liquid-crystal shutter is placed in front of the monochrome CRT. By driving the shutter at 60 Hz, and the CRT display monitor’s Z axis at a high (two times normal) dot rate, the red, green, and yellow combination color scheme is produced. The display monitor is broken into four major blocks. These blocks include CRT monitor, deflection and high-voltage circuitry, cell driver, and liquidcrystal shutter.

Chapter 3: Theory of Operation

A20/A30 - Optical Plug-in

The optical plug-in can contain up to two optical modules to support measurements of

different fiber types and different wavelengths. The optical plug-in provides the laser sources, optical receiver, and digitizer to supply measurement data to the TFP2A mainframe for making accurate distance and loss measurements on optical fiber. An optical switch supports a variety of masking modes for improved accuracy and resolution of singlemode and 1300nm multimode measurements.

‘

TFP2A FiberMaster Module-Level Service Manual 3-5

Chapter 3: Theory of Operation

3-6 TFP2A FiberMaster Module-Level Sevice Manual

4 Maintenance

This chapter contains the information you need to do periodic and corrective

maintenance on the FiberMaster OTDR. The following topics are covered:

❏ Inspection and cleaning ❏ Functional tests ❏ Performance verification ❏ Adjustments ❏ Troubleshooting and diagnostics ❏ Removal and installation procedures

If your instrument does not function properly, take corrective measures immediately;

otherwise additional problems may develop within the instrument.

Product Service

To assure prompt product service and maintenance for our instruments, Tektronix

has established field offices and service centers throughout the United States and outside the U.S. in countries where our products are sold. Contact your local service center, representative, or sales engineer for details regarding warranty, calibration, emergency repair, repair parts, scheduled maintenance, maintenance agreements, pick-up and delivery, and other services available through these centers. Or in the U.S. and Canada, telephone toll free 1-800-835-9433.

An emergency repair service is available to provide immediate attention if your

instrument malfunctions in an emergency situation. To receive this service, contact any Tektronix service center or call 1-800-835-9433.

Recalibration

Tektronix recommends that the TFP2A be sent to the factory or a qualified Tektronix

service center for recalibration every 12 months. To arrange for recalibration, contact any Tektronix service center or call 1-800-835-9433.

TFP2A FiberMaster Module-Level Service Manual 4-1

Chapter 4: Maintenance

Static-Sensitive Components

CAUTION

Static discharge can damage any semiconductor component in this instrument.

When performing any service that requires internal access to the instrument, take the

following precautions to avoid damaging internal modules and their components with electrostatic discharge (ESD).

1. Minimize handling of static-sensitive modules.

2. Transport and store static-sensitive modules in their static-protected containers or

on a metal rail. Label any package that contains static-sensitive modules.

3. Discharge the static voltage from your body by wearing a grounded antistatic wrist

strap while handling these modules. Service the modules only at a static-free workstation.

4. Do not allow anything capable of generating or holding a static charge on the

workstation surface.

5. Handle circuit boards by the edges whenever possible.

6. Do not slide the modules over any surface.

7. Avoid handling the modules in areas that have carpeted floors or work surfaces

capable of generating static charges.

4-2 TFP2A FiberMaster Module-Level Service Manual

Inspection and Cleaning Procedures

FiberMaster’s cabinet minimizes dust accumulation inside the instrument. Never

operate the OTDR without the cabinet installed. When storing or transporting the instrument, make sure the front cover is on to protect the front panel and display from dust and damage.

Inspect and clean your FiberMaster OTDR as often as operating conditions require.

For example, under average conditions (laboratory use), inspect and clean your instrument after every 1000 hours of operation. When using FiberMaster extensively in the field, inspect and clean it after every 500 hours of operation. Dirt acts as a thermal insulator and can cause overheating and component breakdown. It also provides an electrical conduction path that could cause instrument failure, especially under high-humidity conditions.

Exterior Inspection

Inspect the outside of the OTDR for damage, wear, and missing parts, using table 4-1

as a guide. OTDRs that appear to have been dropped or otherwise abused should be checked thoroughly to verify correct operation and performance.

Chapter 4: Maintenance

Table 4-1. External Inspection Checklist

Item Inspect For Repair Action

Cabinet, front panel Cracks, scratches, Replace defective module. cover, handle deformations, damaged

hardware or gaskets, proper operation of handle

Front-panel knobs Missing, damaged, or loose Repair or replace missing or

knobs damaged knobs.

Connectors Broken shells, cracked Replace defective modules.

insulation, deformed contacts. Clear or wash out dirt. Dirt in connectors.

Accessories Missing items or parts of Replace damaged or

items, bent pins, broken or missing items, frayed frayed cables, and damaged cables, and defective connectors. modules.

TFP2A FiberMaster Module-Level Service Manual 4-3

Chapter 4: Maintenance

Exterior Cleaning

CAUTION

To prevent getting moisture inside the OTDR during external cleaning, use only enough liquid to dampen the cloth or applicator.

1. Remove dust from the outside of the instrument by wiping with a lint-free cloth or

brushing the surface with a small brush. Use the brush to remove dust from around the front-panel controls.

2. Clean remaining dirt with a lint-free cloth dampened in a general-purpose

detergent-and-water solution. Do not use abrasive cleaners.

3. Clean the monitor screen with a lint-free cloth dampened with isopropyl alcohol.

Optical-Fiber Cleaning

As a rule, clean any fiber before connecting it to FiberMaster’s front panel, or at any

time you think it may be contaminated. Clean the connector using electronics-grade isopropyl alcohol on a lint-free swab, then blow dry with clean, canned air. If you know the connector is clean, blowing with air should be sufficient.

CAUTION

Cleaning and Changing the Front-Panel Connector

Never use any abrasive material to clean the fiber. Damage to the fiber results in deteriorated performance.

Newer FiberMaster optical modules have cleanable, universal front-panel connectors,

while older modules do not. The universal connector system is identified by the nomenclature FREE and LOCK printed on the adapter plate inside the door of the optical connector assembly. Clean both types of connectors before connecting a fiber, and when changing connector adapters on the universal connectors.

Clean FiberMaster’s old-style front-panel connector with electronics-grade isopropyl

alcohol and a small lint-free swab. Insert the end of the swab into the connector, roll it gently, then blow dry using canned air.

Clean or change the universal connector system following the steps below. The tools

you will need are:

❏ Flat-blade screwdriver ❏ Lint-free swab ❏ Pipe cleaner ❏ Electronics-grade isopropyl alcohol ❏ Optical-grade canned air

1. Lift the door of the optical connector assembly.

2. Using the flat-blade screwdriver, rotate the FREE-LOCK screw in either direction

until it is aligned vertically with the FREE position, then rotate it back to the LOCK position. This releases the connector from the universal interface assembly.

4-4 TFP2A FiberMaster Module-Level Service Manual

Chapter 4: Maintenance

3. Unscrew the connector by holding it around the connector knurling and turning it

counterclockwise until it rotates freely. Remove the connector.

4. Dampen the pipe cleaner with alcohol and draw it through the connector barrel.

5. Dampen a lint-free swab with alcohol and swab the ferrule. The ferrule must be

clean, otherwise it can deposit dirt into the optical connector.

6. Blow dry the connector barrel and the ferrule with canned air.

7. Dampen a second lint-free swab with alcohol and gently roll it over the end of the

fiber. Do not scrub; this can scratch the polished end.

8. Gently blow dry the fiber end with canned air.

9. Replace the connector over the universal interface. Applying light pressure,

rotate the connector barrel (the end of the connector) until it locks in the keyed position.

10. Screw the connector back in by holding it around the connector knurling and

turning it clockwise until finger tight.

11. Using the screwdriver, turn the FREE-LOCK screw to align it vertically with the

FREE position.

12. Push the connector assembly into the module until it stops. While holding the

connector in, rotate the FREE-LOCK screw back to the LOCK position. Release the connector.

universal interface (pigtail)

ferrule

fiber

connector knurling

connector

connector barrel

pipe

FREE – LOCK

screw

swab

cleaner

Figure 4-1. Cleaning and Changing the Universal Connector

TFP2A FiberMaster Module-Level Service Manual 4-5

Chapter 4: Maintenance

Interior Inspection

To gain access to the inside of the OTDR for inspection and cleaning, refer to the

removal and replacement procedures given later in this chapter.

Inspect the internal portion of your FiberMaster OTDR for damage and wear, using

table 4-2 as a guide. Repair any deficiencies found immediately.

CAUTION

To prevent damage from electrical arcing, make sure that circuit boards and components are dry before applying power to the OTDR.

Table 4-2. Internal Inspection Checklist

Item Inspect For Repair Action

Circuit boards Loose, broken, or corroded Remove failed module and

solder connections. Burned replace with a new module circuit board. Burned, broken, or cracked circuit-run plating.

Resistors Burned, cracked, broken, or Remove failed module and

blistered replace with a new module.

Solder connections Cold solder or rosin joints Resolder joint and clean with

isopropyl alcohol.

Capacitors Damaged or leaking cases. Remove damaged module

Corroded solder on leads or and replace with a new terminals. module.

Semiconductors Loosely inserted in sockets. Firmly seat loose

Distorted pins. semiconductors. Remove

devices with distorted pins, carefully straighten pins, (as required to fit socket) using long-nose pliers, and reinsert firmly. Ensure that straightening action does not cause pins to crack or break off.

Wiring and cables Loose plugs or connectors. Firmly seat connectors.

Burned, broken, or frayed Repair or replace modules wiring. that have defective wiring

or cables.

Chassis Dents, deformation, and Straighten, repair, or

damaged hardware replace defective hardware.

4-6 TFP2A FiberMaster Module-Level Service Manual

Interior Cleaning

Chapter 4: Maintenance

NOTE

If a module is clean upon inspection after steps 1 and 2, skip the remaining steps.

1. Blow dust out of interior using dry, low-pressure, deionized air (approximately

9 psi).

2. Remove any remaining dust with a lint-free cloth dampened in a 75% isopropyl

alcohol solution, and rinse with warm deionized water. Lint-free swabs are useful for cleaning in narrow spaces and on circuit boards.

3. If steps 1 and 2 do not remove all the dust or dirt, you can spray wash the OTDR

using a solution of 75% isopropyl alcohol as described in steps 4 through 8.

4. Expose the parts to be cleaned by removing easily accessible shields and panels

(refer to the removal and replacement procedures given later in this chapter).

5. Spray wash dirty parts with the isopropyl alcohol solution and wait 60 seconds for

the majority of the alcohol to evaporate.

6. Thoroughly rinse the parts using hot (120 to 140 degrees F) deionized water.

7. Dry all parts with low-pressure, deionized air.

8. Dry all components and assemblies in an oven or drying compartment with low-

temperature (125 to 150 degrees F) circulating air.

Lubrication

Components in the FiberMaster OTDR do not require lubrication.

TFP2A FiberMaster Module-Level Service Manual 4-7

Chapter 4: Maintenance

Terminal Interface

Some of the functional tests and performance verification procedures described in the

following pages use FiberMaster’s terminal interface. Access to this interface requires that you connect the OTDR to a VT-100-compatible dumb terminal, using a serial cable configured with a special connector to achieve the proper pin connections. You can make the connector yourself, using the following parts and tools:

❏ 25-pin DSUB male connector, solder cup, Tek part number 131-0570-00

(manufacturer: Cannon, part number DB-25P)

❏ 25-pin DSUB female connector, wirewrap, Tek part number 131-1437-00

(manufacturers: Cannon, part number DB25S-F179; or Souriau Inc., part number DB25S-631)

❏ Fine-tip soldering iron ❏ Wire cutters

1. Cut wirewrap pins 14 and 16 from the female connector.

2. Solder pin 2 on the female connector to pin 14 on the male connector

3. Solder pin 3 on the female connector to pin 16 on the male connector.

4-8 TFP2A FiberMaster Module-Level Service Manual

Chapter 4: Maintenance

4. Solder pin 1, pins 4 through 13, pin 15, and pins 17 through 25 on the female

connector straight across to the corresponding pins on the male connector, as shown in figure 4-2,

Male

Female

Pin 3

Pin 2

Pin 16

CAUTION

Pin 14

Figure 4-2. Terminal Interface Connector

Connect FiberMaster to the terminal by plugging the terminal interface connector into

the RS-232 port on FiberMaster’s back panel. Then plug an RS-232 cable into the connector and into the RS-232 connector on the terminal. The main menu of FiberMaster’s terminal interface displays on the terminal screen.

When using the TFP2A terminal interface to perform functional tests and perfomance verification, restrict menu use only to those procedures given in this manual. Most of the terminal interface menus are intended for factory use only, and some of the functions can damage the instrument if used improperly.

TFP2A FiberMaster Module-Level Service Manual 4-9

Chapter 4: Maintenance

Functional Tests

The purpose of these procedures is to confirm that Fibermaster is functioning

properly. These tests verify that the OTDR and its options are functioning. They do not verify that they operate within specified limits. Instrument operation within limits is checked in the

Mainframe Checks

Equipment required:

❏ External AT-compatible keyboard ❏ VT-100-compatible dumb terminal ❏ RS-232 cable with terminal interface connector ❏ CRT template (The template is located on a mylar sheet at the back of this

manual. To use, cut out the template along its outer edge.)

❏ Five-kilometer multimode or singlemode test fiber

1. Connect the FiberMaster’s RS-232 port to the terminal’s R-S232 port.

Performance Verification

section, which follows this section.

2. Plug the external keyboard into the keyboard connector on FiberMaster’s front

panel.

3. Press the POWER button on the FiberMaster. After power-up diagnostics are

complete, the start-up screen displays.

Figure 4-3. The Start-Up Screen

4-10 TFP2A FiberMaster Module-Level Service Manual

Chapter 4: Maintenance

4. Verify the software version numbers are correct.

5. Verify that the date and time are correct.

6. Check that the display characteristics (focus, color, size, etc.) are normal. The

corners of the display may be slightly out of focus, but must be legible.

7. Set the serial-port baud rates on the OTDR and the terminal to 9600 baud. Set the

FiberMaster’s baud rate as follows:

✔ Press the Change Settings softkey. ✔ Press the Next Menu softkey twice to go to the System Settings menu. ✔ Press the Next Param or Prev Param softkey until the RS-232 Baud Rate

parameter is highlighted.

✔ Turn the CURSOR knob to highlight the 9600 baud rate selection. ✔ Press the Exit softkey to return to the start-up screen.

8. Enter the Run Diagnostics menu by pressing the Help and Change Settings

softkeys simultaneously, then rotating the CURSOR knob.

9. Verify that there were no diagnostics failures during the power-on testing. If a

failure occurred during power-on, a Self Test softkey displays on the start-up screen, allowing direct entry to the Run Diagnostics menu. The failed test is noted on the Run Diagnostics menu screen.

10. Turn the CURSOR knob until the front-panel test is highlighted on the Run

Diagnostics menu. Press the Select Test softkey.

11. Press the Start Test softkey. Verify operation of all front-panel controls and

keyboard. After testing the front-panel controls, press softkey 1 then softkey 3 to exit the test.

12. Display CRT alignment pattern:

✔ At the terminal, the Main Menu of the terminal interface should be displayed.

Type 3 on the terminal keyboard to select item 3 on the menu, Diagnostics Menu.

✔ On the Diagnostics Menu, select item 3, Select Display Tests. ✔ On the Display Tests menu, select item 1, Display Hold Time. Enter the

number of seconds to display the test pattern that you will use to align the display. For example, to display the test pattern for two minutes, enter 120.

✔ Select item 5, Alignment Pattern, and the alignment pattern displays on the

CRT.

13. Place the CRT template over the display.

14. Verify that the alignment pattern closely matches the template (horizontal and

vertical lines only).

15. On the FiberMaster, press the Exit softkey to return to the start-up screen.

TFP2A FiberMaster Module-Level Service Manual 4-11

Chapter 4: Maintenance

16. Press theChange Settings softkey. The instrument enters the Waveform Settings

menu.

17. Press the Next Menu softkey. The Operator Settings menu displays. Press Next

Param or Prev Param softkey until the Fiber ID window is displayed on the screen.

18. Type in 12 to 15 characters from the external keyboard connected to the

FiberMaster, and check that the same characters are displayed in the Fiber ID window.

19. Press the Exit softkey to return to the start-up screen.

20. Select a wavelength by pressing the MODULE SELECT button until the LED next to

your selected optical module lights up.

21. Connect the test fiber to the connector on the selected optical module.

22. Press the START/STOP button to start data acquisition. The optical module LED

flickers to indicate that the laser is firing, and the acquisition screen displays.

23. Check that a waveform is acquired and displayed on the acquisition screen.

4-12 TFP2A FiberMaster Module-Level Service Manual

Internal RAM (if installed)

1. Connect the FiberMaster’s RS-232 port to the terminal’s RS-232 port, using the

specified cable.

2. Set the serial-port baud rates on the OTDR and the terminal to 9600 baud. Set the

FiberMaster’s baud rate as follows:

✔ Press the Change Settings softkey. ✔ Press the Next Menu softkey twice to go to the System Settings menu. ✔ Press the Next Param or Prev Param softkey until the RS-232 Baud Rate

parameter is highlighted.

✔ Turn the CURSOR knob to highlight the 9600 baud rate selection. ✔ Press the Exit softkey to return to the start-up screen.

3. On the terminal keyboard, type 3 to select the Diagnostics Menu item on the Main

Menu.

4. On the Diagnostics Menu, select item 4, Select Disk Tests.

5. Press 4 on the terminal keyboard to change the Toggle Active Drive selection to

the fixed drive.

Chapter 4: Maintenance

6. Press A on the terminal keyboard to select the Data Test option. The test stores a

hex value into all the RAM memory, then reads it back and compares it to the original value. Any addresses not matching are displayed on the screen. Successful completion of the test causes the message Data Test Passed to be reported.

7. On the terminal keyboard, type 0 twice to return to the Main Menu.

8. On FiberMaster, press the Mass Storage softkey.

9. Press the Next Menu softkey twice to go to the Format menu.

10. Press the Format Fixed softkey. A prompt displays on the screen to inform you

that if you format the fixed drive, all information on the drive is lost. Press the Yes softkey to begin formatting.

11. When formatting is complete, press Exit to go to the acquisition screen.

TFP2A FiberMaster Module-Level Service Manual 4-13

Chapter 4: Maintenance

Internal Printer Test (if installed)

1. If the start-up screen or the Run Diagnostics menu is not currently displayed, cycle

power to FiberMaster to display the start-up screen.

2. Press the HELP button and Change Settings softkey simultaneously to go to the

Run Diagnostics menu.

3. Turn the CURSOR knob to highlight the Printer test.

4. Press the Select Test softkey.

5. Press the START TEST softkey.

6. The printer prints a test pattern. Check for even intensity across the full width of the

print.

7. Press Exit to return to the start-up screen.

8. Check that the printer cover closes completely.

External Printer Test (if used)

1. From the start-up screen, press the Change Settings softkey.

2. Press the Next Menu softkey twice to go to the System Settings menu.

3. Press the Next Param softkey until the Hard Copy parameter is highlighted.

4. Turn theCURSOR knob to change the hardcopy device to the type of printer you use.

5. Press the Exit softkey.

6. Connect the printer cable to the appropriate connector on the back of the

FiberMaster (RS-232 or GPIB).

7. Press the HARD COPY button and check that the external printer prints a copy of the

display.

4-14 TFP2A FiberMaster Module-Level Service Manual

Disk Drive Test (if installed)

1. Insert a blank, unformatted floppy disk into the disk drive.

2. From the start-up screen, press the Mass Storage softkey.

3. Press the Next Menu softkey twice to go to the Format menu.

4. Press the Format softkey to format the floppy disk. (Note that if internal RAM is

installed in your instrument you must press the Format Removable softkey to format the floppy disk.)

5. A prompt displays, asking you to confirm the format operation. Press the Yes

softkey.

6. After the format is complete, remove the disk from the drive and insert it into the

floppy disk drive of an IBM PC or compatible.

7. At the PC, type the following command:

dir <drive designator>:

In place of <drive designator>, type the letter designator of the floppy disk drive, usually a or b.

Chapter 4: Maintenance

8. Verify that the response on the PC screen reads:

Volume in drive <drive designator>: is FIBERMASTER

If the PC does not display the statement above, there is a formatting problem with FiberMaster’s disk drive.

9. Remove the disk from the PC drive and return it to the TFP2A.

10. Return to the FiberMaster start-up screen by cycling power to the OTDR.

11. Enter the Run Diagnostics menu by pressing theChange Settings softkey and the

HELP button simultaneously.

12. Select the mass storage tests by turning the CURSOR knob until the test is

highlighted. Then press the Select Test softkey.

13. Run the mass storage tests by pressing the START TEST softkey.

14. Verify successful completion of the mass storage tests by pressing the More Info

softkey.

15. Press the OK softkey to return to the Run Diagnostics menu, then Exit to return to

the start-up screen.

TFP2A FiberMaster Module-Level Service Manual 4-15

Chapter 4: Maintenance

Performance Verification

The following performance checks describe procedures to verify that FiberMaster is

performing properly and meets the specifications listed in chapter 1. Optical plug-in module(s) must be installed in the TFP2A mainframe, with all covers in place, and warmed up for a minimum of 20 minutes before starting the performance verification.

Equipment Required

❏ 3/32 Allen wrench ❏ Two-kilometer singlemode or multimode test fiber ❏ Four-kilometer multimode test fiber ❏ 25-kilometer singlemode test fiber ❏ Jumper cables ❏ Tektronix DC508 (or equivalent) frequency counter ❏ Tektronix OA5002 (or equivalent) optical attenuator ❏ Tektronix OA5022 (or equivalent) optical attenuator ❏ Tektronix TFC200 power meter with 20-dB attenuator (FL module only) ❏ VT-100-compatible dumb terminal ❏ RS-232 cable with terminal interface connector (described in the previous

Functional Tests

❏ Data sheets (provided in appendix A)

Clock Frequency

Equipment required:

❏ 3/32 Allen wrench ❏ Tektronix DC508 (or equivalent) frequency counter

1. Press POWER to turn off power to the TFP2A.

2. Remove the bottom case half from the TFP2A mainframe by removing four Allen-

head screws, two on each side.

3. Press POWER to turn on the TFP2A.

4. Connect the DC508 frequency counter to the S40 test point located near the rear

corner of the control board.

section)

5. Verify that the frequency is 40 MHz ± 400 Hz.

6. Turn off power to the TFP2A and re-install the bottom cover of the TFP2A.

4-16 TFP2A FiberMaster Module-Level Service Manual

Verify Clock Phase

Equipment required:

❏ 3/32 Allen wrench ❏ 2465B oscilloscope

1. Connect the positive lead of a DMM to the VCO test point and the negative lead

ground.

2. Verify the DMM read 4.0 volts (+/-.25). The VCO adjust (C40320) may be adjusted

if required.

3. Connect channel A input of the 2465 oscilloscope to the PLOCK test point.

4. Connect channel B input of the 2465 oscilloscope to the SLOCK test point.

5. Set the 2465 horizontal time/div to 100 nsec/div. Set the 2465 vertical to 5 volts/div

on both channels.

6. Set the 2465 triggering to channel 1. Adjust the triggering to display the pulses from

the SLOCK and PLOCK test points.

Chapter 4: Maintenance

7. Verify the rising edges of these pulses are less than 5 nsec apart. If greater than 5

nsec, replace the control board

8. Remove all test leads from the TFP2A.

TFP2A FiberMaster Module-Level Service Manual 4-17

Chapter 4: Maintenance

Front-Panel Loss

Equipment required:

Front-panel loss

Backscatter from fiber under test

Backscatter from internal fiber

0 km

Figure 4-4. Front-Panel Loss

❏ Two-kilometer or longer singlemode or multimode test fiber ❏ One-meter jumper ❏ Data sheet (provided in appendix A)

All dynamic range specifications assume a loss of one dB or less at the front panel.

To check the front-panel loss, follow these steps:

1. Connect a four-kilometer test fiber to the FiberMaster using a one-meter test

jumper.

2. Turn on power to the instrument by pressing the POWER button.

3. Press the MODULE SELECT button to choose the laser source.

4. Set the pulse width to 20 meters (2 meters for 850 nm) and the range to 50

kilometers as follows:

✔ Press the Change Settings softkey. ✔ Press the Next Param or Prev Param softkey until the Pulse Width menu is

highlighted.

✔ Turn the CURSOR knob to highlight the 20-meter pulse-width selection (2

meters for 850 nm).

✔ Press Next Param to highlight the Maximum Range setting. ✔ Turn the CURSOR knob to select the 50-km range selection. ✔ Press the Exit softkey to return to the start-up screen.

5. Start an acquisition by pressing the START/STOP button.

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Chapter 4: Maintenance

6. Press the Splice Loss softkey to enter Splice Loss mode.

7. Move the distance cursor to the front-panel reflection at 0 kilometers. Expand the

view if necessary for precise cursor placement by pressing the EXPAND button.

8. If manual adjustments to the loss cursors are necessary, use the vertical and slope

LOSS knobs to adjust the left loss cursor to the internal fiber backscatter, and the

right loss cursor to the backscatter of the fiber under test. Press theCURSOR SELECT button to switch between the distance cursors.

9. Note the splice loss for the front-panel reflection and record on the data sheet.

10. If the front-panel loss exceeds one dB, check the connection at the front panel and

clean the connectors, or try a different jumper cable.

TFP2A FiberMaster Module-Level Service Manual 4-19

Chapter 4: Maintenance

Dynamic Range

Dynamic Range (dB)

~2.4 dB

Figure 4-5. Dynamic Range Measurements

~1.8 dB

3 σ

98%

SNR = 1

NOTE

Dynamic range is defined as the difference between the backscatter level at the start

of the fiber (extrapolated through the front-panel reflection to the front panel) and the noise level, as follows:

❏ Dynamic range, SNR = 1, measures the difference between the backscatter and

the RMS noise level. This is at about the 68.3% level of the noise.

❏ Dynamic range, SNR = 3 sigma, measures the difference between the

backscatter and the 99.5% of the noise level (i.e., one or two noise peaks may exceed this level when measuring 1000 data points of noise).

❏ Dynamic range, 98%, measures the difference between the backscatter and the

98% level of the noise.

There are two methods of measuring dynamic range given in the following pages.

Method 1 involves an automatic calculation of the noise floor, measured via FiberMaster’s terminal interface. This method requires a VT-100-compatible terminal and a special cable connection (described earlier in this chapter), and accurately establishes the noise floor. Method 2 does not need special equipment, but requires you to estimate the 98% level of the noise and can yield less precise results.

Dynamic Range Method 1, which provides an automatic calculation of the noise floor, varies slightly when testing an FL-series optical module (vs. an FS-, FG-, or FM-type module). Therefore, two versions of method 1 for testing dynamic range are given. The first one applies to the FS-, FG-, and FM-series modules, and the second applies to the FL series.

4-20 TFP2A FiberMaster Module-Level Service Manual

Chapter 4: Maintenance

FS/FG/FM-Series Dynamic Range Measurement—Method 1 Equipment required:

❏ VT-100-compatible dumb terminal ❏ RS-232 cable with terminal interface connector (described in the previous

Functional Tests

section)

❏ Two-kilometer or longer singlemode or multimode test fiber ❏ Data sheet (provided in appendix A)

1. Connect the FiberMaster’s RS-232 port to the terminal’s RS-232 port, using the

specified cable.

2. Set the serial-port baud rates on the OTDR and the terminal to 9600 baud. Set the

FiberMaster’s baud rate as follows:

✔ Turn power on to the instrument by pressing the POWER button. ✔ Press the Change Settings softkey. ✔ Press the Next Menu softkey twice to go to the System Settings menu. ✔ Press the Next Param or Prev Param softkey until the RS-232 Baud Rate

parameter is highlighted.

✔ Turn the CURSOR knob to highlight the 9600 baud rate selection. ✔ Press the Exit softkey to return to the start-up screen.

3. Connect the test fiber to the instrument using a one-meter jumper.

4. Select a wavelength by pressing the MODULE SELECT button until you reach the

desired wavelength.

5. Select pulse width and maximum range settings.

✔ Press the Change Settings softkey. ✔ Press the Next Param or Prev Param softkey until the Pulse Width menu is

highlighted.

✔ Turn the CURSOR knob to select the pulse width. ✔ Press Next Param to highlight the Maximum Range menu. ✔ Turn the CURSOR knob to select the range. ✔ Press the Exit softkey to return to the start-up screen.

6. At the terminal, the Main Menu is displayed. Type 1 on the terminal keyboard to

select item 1 on the Main Menu, RMS Settings Menu. The Waveform RMS Settings Menu is displayed.

7. Type 2 on the terminal keyboard to turn on Two-Point RMS.

TFP2A FiberMaster Module-Level Service Manual 4-21

Chapter 4: Maintenance

8. Make sure item 4 is set to RMS Reported Average (waveform baseline). If the

RMS Reported Average item is set to linear average, press 4 to switch to waveform baseline.

9. Type 0 to return to the Main Menu.

10. On the Main Menu, select item 2, Acquisition Diagnostics Menu.

11. On the Acquisition Menu, select item D, MISC ACQUISITION ON/OFF MENU 2.

12. On the MISC ACQUISITION ON/OFF MENU 2, select item 1 to turn on the Use

opposite laser plugin selection in acq option. This option causes the opposite laser source to the one selected (the laser source in the non-active plug-in module) to be used in the next acquisition. The active laser source then detects only noise, allowing the instrument to calculate the noise level for that wavelength.

13. Set the number of averages to 32,768.

✔ Press the Change Settings softkey. ✔ Press the Next Param or Prev Param softkey until the Maximum Averages

menu is highlighted.

✔ Turn the CURSOR knob clockwise to increase the number of averages to

32,768.

✔ Press the Exit softkey to return to the start-up screen.

14. Start an acquisition on the FiberMaster by pressing the START/STOP button.

15. Press the Two Point softkey to enter Two Point mode.

16. Set the distance cursors at approximately one kilometer in from the ends of the

displayed range. For example, if the maximum range is set to 25 kilometers, place the distance cursors at about 1 and 24 kilometers.

17. The FiberMaster calculates the RMS noise level and displays it in the upper right-

hand corner of the screen. The data might look like this:

RMS = 2352 [4.1] (-88 [-0.2])

The RMS (1 Sigma) noise level is given in dB in the first bracketed number; in this example, it is 4.1. Record the RMS noise level on the data sheet.

18. Repeat steps 5 and 14 through 17 for each pulse width and range as required.

19. On the terminal, the MISC ACQUISITION ON/OFF MENU 2 is still displayed. Type

1 on the terminal keyboard to turn off the Use opposite laser plugin selection in acq option.

20. Type 0 to go back to the Acquisition Menu, then 0 again to go to the Main Menu.

21. Type 1 to go to the Waveform RMS Settings Menu.

22. On the Waveform RMS Settings Menu, type 2 to turn off the Two Point RMS

option, then type 0 to return to the Main Menu.

4-22 TFP2A FiberMaster Module-Level Service Manual

Chapter 4: Maintenance

23. On the FiberMaster, set the maximum number of averages back to 1024.

✔ Press the Change Settings softkey. ✔ Press the Next Param or Prev Param softkey until the Maximum Averages

menu is highlighted.

✔ Turn the CURSOR knob counterclockwise to decrease the number of averages

to 1024.

✔ Press the Exit softkey to return to the acquisition screen.

24. Press the CURSOR SELECT button (if necessary) to select the right-hand distance

cursor.

25. Set the active loss cursor to a straight horizontal line at 0 dB, using the LOSS knobs.

26. Press the CURSOR SELECT button to activate the left-hand distance cursor. Turn the

CURSOR knob to move this cursor to 0 kilometers.

27. Use the LOSS knobs to align the active loss cursor with the backscatter.

28. Record the two-point loss figure on the data sheet. (The two-point loss is shown in

dB near the active distance cursor.)

29. Calculate the dynamic range by subtracting the 1 Sigma noise level recorded in

step 17 from the two-point loss recorded in step 28. Record the result on the data sheet.

30. Reset instrument settings and start a new acquisition for each pulse width and

range combination on the data sheet. Repeat steps 27 through 29 each time. You do not need to reset the 0 dB level at the right-hand loss cursor for each new acquisition.

31. Repeat steps 4 through 30 for each wavelength.

TFP2A FiberMaster Module-Level Service Manual 4-23

Chapter 4: Maintenance

FL-Series Dynamic Range Measurement—Method 1 Equipment required:

❏ VT-100-compatible dumb terminal ❏ RS-232 cable with terminal interface connector (described in the previous

Terminal Interface

section in this chapter)

❏ Two-kilometer or longer singlemode test fiber ❏ Data sheet (provided in appendix A)

1. Connect the FiberMaster’s RS-232 port to the terminal’s RS-232 port, using the

specified cable.

2. Set the serial-port baud rates on the OTDR and the terminal to 9600 baud. Set the

FiberMaster’s baud rate as follows:

parameter is highlighted.

✔ Turn the CURSOR knob to highlight the 9600 baud rate selection. ✔ Press the Exit softkey to return to the start-up screen.

3. Connect the test fiber to the instrument using a one-meter jumper.

4. Select a wavelength by pressing the MODULE SELECT button until you reach the

desired wavelength.

5. Select pulse width and maximum range settings.

✔ Press the Change Settings softkey. ✔ Press the Next Param or Prev Param softkey until the Pulse Width menu is

highlighted.

6. At the terminal, the Main Menu is displayed. Type 1 on the terminal keyboard to

select item 1 on the Main Menu, RMS Settings Menu. The Waveform RMS Settings Menu is displayed.

7. Type 2 on the terminal keyboard to turn on Two-Point RMS.

8. Make sure item 4 is set to RMS Reported Average (waveform baseline). If RMS

Reported Average is set to linear average, press 4 to switch to waveform baseline.

4-24 TFP2A FiberMaster Module-Level Service Manual

Chapter 4: Maintenance

9. Type 0 to return to the Main Menu.

10. On the Main Menu, select item H, FL Module Diagnostics Menu.

11. On the FL Module Diagnostics Menu, select item 6, MISC ACQUISITION ON/OFF

MENU.

12. On the MISC ACQUISITION ON/OFF MENU, select item 1 to turn on the Use

opposite laser plugin selection in acq (on) option. This option causes the opposite laser source to the one selected (the laser source in the non-active plugin module) to be used in the next acquisition. The active laser source then detects only noise, allowing the instrument to calculate the noise level for that wavelength.

13. Set the number of averages to 262,144.

✔ Press the Change Settings softkey. ✔ Press the Next Param or Prev Param softkey until the Maximum Averages

menu is highlighted.

✔ Turn the CURSOR knob clockwise to increase the number of averages to

262,144.

✔ Press the Exit softkey to return to the start-up screen.

14. Start an acquisition on the FiberMaster by pressing the START/STOP button.

15. Press the Two Point softkey to enter Two Point mode.

16. Set the distance cursors at approximately one kilometer in from the ends of the

displayed range. For example, if the maximum range is set to 25 kilometers, place the distance cursors at about 1 and 24 kilometers.

17. The FiberMaster calculates the RMS noise level and displays it in the upper right-

hand corner of the screen. The data might look like this:

RMS = 2352 [4.1] (-88 [-0.2])

The RMS (1 Sigma) noise level is given in dB in the first bracketed number; in this example, it is 4.1. The mean noise level appears in the second bracketed number; in the example it is -0.2. Record the RMS noise level and the mean noise level on the data sheet.

18. Repeat steps 5 and 14 through 17 for each pulse width and range as required.

19. On the terminal, the MISC ACQUISITION ON/OFF MENU is still displayed. Type

1 on the terminal keyboard to turn off the Use opposite laser plugin selection in acq (on) option.

20. Type 0 to go back to the FL Module Diagnostics Menu, then 0 again to go to the

Main Menu.

21. Type 1 to go to the Waveform RMS Settings Menu.

22. On the Waveform RMS Settings Menu, type 2 to turn off the Two Point RMS

option, then type 0 to return to the Main Menu.

TFP2A FiberMaster Module-Level Service Manual 4-25

Chapter 4: Maintenance

23. On the FiberMaster, set the maximum number of averages back to 1024.

✔ Press the Change Settings softkey. ✔ Press the Next Param or Prev Param softkey until the Maximum Averages

menu is highlighted.

✔ Turn the CURSOR knob counterclockwise to decrease the number of averages

to 1024.

✔ Press the Exit softkey to return to the acquisition screen.

24. Note the baseline difference numbers reported on the VT100 terminal. These are

used to adjust the baseline value to account for calibration offset.

25. Press the CURSOR SELECT button (if necessary) to select the right-hand distance

cursor.

26. Set the active loss cursor to a straight horizontal line at 0 dB, using the LOSS knobs.

27. Press the CURSOR SELECT button to activate the left-hand distance cursor. Turn the

CURSOR knob to move this cursor to 0 kilometers.

28. Use the LOSS knobs to align the active loss cursor with the backscatter.

29. Record the two-point loss figure on the data sheet. (The two-point loss is shown in

dB near the active distance cursor.)

30. Calculate the dynamic range by the following formula: scattering level + front-panel

loss - mean noise level - RMS noise level - baseline difference - 0.5. Record the result on the data sheet.

31. Reset instrument settings and start a new acquisition for each pulse width and

range combination on the data sheet. Repeat steps 27 through 29 each time. You do not need to reset the 0 dB level at the right-hand loss cursor for each new acquisition.

32. Repeat steps 4 through 31 for each wavelength.

4-26 TFP2A FiberMaster Module-Level Service Manual

Tektronix TFP2A Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

WARNING

TFP2A FiberMaster Module-Level Service Manual

Table of Contents

List of Illustrations

List of Tables

Safety Information

Definition of Terms and Symbols

Power Source

Grounding the Instrument

Danger Arising from Loss of Ground

Use the Proper Power Cord

Use the Proper Fuse

Do Not Operate in Explosive Atmospheres

Do Not Remove Covers or Panels

Laser Radiation

Repair

ATTENTION!

Product Description

Modular, Plug-In Laser Sources

Accurate, High-Speed Data Acquisition and Measurement

Automatic and Manual Event Marking

Extended Memory and Storage Capacity

Hardcopy Options

Remote Control Capability

Additional Features

Using this Manual

Warranty Information

Tektronix Service

Warranty Service

Self Service

For More Information

Specifications

Accessories and Options

Unpacking and Preparation for Use

Power Source and Power Requirements

CAUTION

Installing the Optical Module(s)

NOTE

Front-Panel Covers

Loading Paper into the Internal Printer

Laser Output

WARNING

Recalibration

Overview of FiberMaster Operation

Advanced Functions

Instrument Configuration

Mass Storage

Basic Operating Procedures

Power on

Read help

Select a wavelength

Set up the system

Start an acquisition

Move the distance cursor

Expand the view

Size the expansion window

Switch active cursors

Adjust loss cursors

Move the waveform

Select a waveform

Store a waveform

Event Table

Two-Point Mode

Splice Loss Mode

Return Loss/Exit Return Loss

Link Return Loss

Event Return Loss

Print

Mass Storage

3 Theory of Operation

4 Maintenance

Recalibration

CAUTION

Inspection and Cleaning Procedures

CAUTION

Cleaning and Changing the Front-Panel Connector