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4-10

Reference

Cleaning Connections for Accurate Measurements

Cleaning Connections for Accurate 
Measurements 

Today, advances in measurement capabilities make connectors and connec-
tion techniques more important than ever. Damage to the connectors on cali-
bration and verification devices, test ports, cables, and other devices can 
degrade measurement accuracy and damage instruments. Replacing a dam-
aged connector can cost thousands of dollars, not to mention lost time! This 
expense can be avoided by observing the simple precautions presented in this 
book. This book also contains a brief list of tips for caring for electrical connec-
tors.

Choosing the Right Connector

A critical but often overlooked factor in making a good lightwave measure-
ment is the selection of the fiber-optic connector. The differences in connec-
tor types are mainly in the mechanical assembly that holds the ferrule in 
position against another identical ferrule. Connectors also vary in the polish, 
curve, and concentricity of the core within the cladding. Mating one style of 
cable to another requires an adapter. Agilent Technologies offers adapters for 
most instruments to allow testing with many different cables. 

Figure 4-2 on 

page 4-11

 shows the basic components of a typical connectors.

The system tolerance for reflection and insertion loss must be known when 
selecting a connector from the wide variety of currently available connectors. 
Some items to consider when selecting a connector are: 

• How much insertion loss can be allowed? 

• Will the connector need to make multiple connections? Some connectors are 

better than others, and some are very poor for making repeated connections. 

• What is the reflection tolerance? Can the system take reflection degradation? 

• Is an instrument-grade connector with a precision core alignment required? 

• Is repeatability tolerance for reflection and loss important? Do your specifica-

book.book  Page 10  Monday, January 7, 2002  2:12 PM

Содержание 83491

Страница 1: ...Agilent 83491 2 3 4A Clock Recovery Modules User s Guide book book Page i Monday January 7 2002 2 12 PM ...

Страница 2: ... improper or inadequate maintenance by Buyer Buyer supplied software or interfac ing unauthorized modifica tion or misuse operation outside of the environmental specifications for the product or improper site preparation or maintenance No other warranty is expressed or implied Agilent Technologies specifically dis claims the implied warranties of merchantability and fitness for a particular purpos...

Страница 3: ...the equipment could be impaired This instrument must be used in a normal condition in which all means for protection are intact only WAR N I N G To prevent electrical shock disconnect the Agilent 83491 2 3 4A from mains before cleaning Use a dry cloth or one slightly dampened with water to clean the external case parts Do not attempt to clean internally WAR N I N G No operator serviceable parts in...

Страница 4: ...iv General Safety Considerations book book Page iv Monday January 7 2002 2 12 PM ...

Страница 5: ... 83491A Specifications 3 3 Agilent 83492A Specifications 3 4 Agilent 83493A Specifications 3 6 Agilent 83494A Specifications 3 7 Agilent 83491 2 3 4A Operating Specifications 3 9 Regulatory Information 3 10 Declaration of Conformity 3 11 4 Reference Front Panel Optical Adapters 4 2 In Case of Difficulty 4 3 Error Messages 4 5 Electrostatic Discharge Information 4 8 Cleaning Connections for Accurat...

Страница 6: ...book book Page 2 Monday January 7 2002 2 12 PM ...

Страница 7: ...1 To install the module 1 3 To connect cables to an Agilent 83492A 1 7 Installation book book Page 1 Monday January 7 2002 2 12 PM ...

Страница 8: ...nectors are easily damaged when connected to dirty or damaged cables and accessories The Agilent 83492A 83493A and 83494A front panel input connectors are no exception When you use improper cleaning and handling techniques you risk expensive instrument repairs damaged cables and compromised measurements Before you connect any fiber optic cable to an Agilent 83492A 83493A or 83494A module refer to ...

Страница 9: ...fice Agilent Technologies will arrange for repair or replacement of damaged or incomplete shipments without waiting for a settlement from the transporta tion company Notify the Agilent Technologies customer engineer of any prob lems 1 Make sure that the serial number listed on the module s rear panel label matches the serial number listed on the shipping document Figure 1 1 Serial number label 2 I...

Страница 10: ...the Agilent 83492 3 4A module s front panel Input connector On Agilent 83492A module s the input connector used depends on the wavelength of the input signal Refer to To connect cables to an Agilent 83492A on page 1 7 5 Connect the supplied adapter cable as shown in Figure 1 3 WAR N I N G Light energy can radiate from the front panel OUTPUT connectors on Agilent 83492A 83493A and 83494A modules Th...

Страница 11: ...ithout first touching the frame of the instrument Be sure that the instrument is properly earth grounded to prevent buildup of static charge C AUT IO N Agilent 83492 3 4A Modules Maximum safe signal input level is 3 dBm 7 On the Agilent 83480A press the Trigger key and then the Source softkey Then select trigger 2 the Agilent 83491 2 3 4A module for the trigger source 8 On the Agilent 83491 2 3 4A...

Страница 12: ...ed A red light does not indicate a problem A red light shows that the adjacent red data rate label is selected A green light shows that the adjacent green data rate label is selected Repeatedly pressing the SELECT key cycles through the selections in one color before switching to the opposite color On Agilent 83491A modules for example the first selec tion cycle shows 155 Mb s selected The second ...

Страница 13: ... on the wavelength of the signal Signals in the 750 nm to 860 nm wavelength range are input to the left connector and output from the right connector Signals in the 1000 nm to 1600 nm wave length range are input to the right connector and output from the left connec tor Figure 1 5 Input and output connections versus wavelength book book Page 7 Monday January 7 2002 2 12 PM ...

Страница 14: ...book book Page 8 Monday January 7 2002 2 12 PM ...

Страница 15: ...To Display a Signal 2 11 To Compensate for Module Insertion Loss 2 12 Using Probes with an Agilent 83491A 2 13 To compensate for a passive probe 2 14 To compensate an Agilent 54701A active probe 2 14 To compensate for other devices 2 15 Operation book book Page 1 Monday January 7 2002 2 12 PM ...

Страница 16: ...ame via a connec tor located on the module s rear panel An external front panel cable passes the data signal with some insertion loss to the receiver module Table 2 1 Module Features Agilent Module Input Connector Selectable Rates Mb s 83491A 50Ω electrical 155 622 1060 1250 2120 2488 2500 83492A Multimode fiber 62 5 125 µm 155 622 1060 1250 2120 2488 2500 83493A Single mode fiber 9 125 µm 155 622...

Страница 17: ...1603B or 71612B error performance analyzers Multimode module and single mode reference receivers Agilent Technologies does not recommend using the Agilent 83492A multi mode module with single mode reference receivers such as the Agilent 83481A 83482A or 83485A B modules Connecting multimode to sin gle mode fibers causes large reflections and insertion loss because of the reduction of the optical f...

Страница 18: ...th the Agilent 83480A digital communica tions analyzer the Agilent 83491 2 3 4A modules do not include Channel keys or menus Also there are no GPIB programming commands for these modules However GPIB programming commands are available for the Agilent 86100A digital commumica tions analyzer book book Page 4 Monday January 7 2002 2 12 PM ...

Страница 19: ...2 5 Operation Front Panel Features Front Panel Features Figure 2 2 Agilent 83491 2 3 4A front panels book book Page 5 Monday January 7 2002 2 12 PM ...

Страница 20: ...a fully regenerated version of the input signal It is intended for monitoring purposes only and not for rigorous eye mask compliance testing The frequency response does not conform to the requirements for eye mask testing as described in ITU T G 957 and Bellcore GR 253 CORE On Agilent 83492A and 83493A modules this port is ampli tude stabilized for input signals greater than approximately 23 dBm O...

Страница 21: ...he available adapters Recovered Clock The recovered clock signal is routed directly to the Agilent 83480A mainframe through the module s rear panel This output has a lower jitter modulation bandwidth than the front panel CLOCK Auxiliary Output Because of the reduced jitter modulation bandwidth on the mainframe trigger signal a more complete view of the jitter on the waveform data is obtained Multi...

Страница 22: ...2 8 Operation Block Diagrams Block Diagrams Figure 2 3 Agilent 83491A Block Diagram Figure 2 4 Agilent 83492A and 83493A Block Diagram book book Page 8 Monday January 7 2002 2 12 PM ...

Страница 23: ...2 9 Operation Block Diagrams Figure 2 5 Agilent 83494A Block Diagram book book Page 9 Monday January 7 2002 2 12 PM ...

Страница 24: ...2 10 Operation Block Diagrams Figure 2 6 Agilent 83494A Option 106 Block Diagram book book Page 10 Monday January 7 2002 2 12 PM ...

Страница 25: ...using a data trigger are less reliable than using a recovered clock Signals triggered on data can also vary depending upon the trigger level Green and red data rate lights The data rate indicator lights on the Agilent 83491 2 3A and Agilent 83494A Option 106 change color between red and green to show which data rate is selected A red light does not indicate a problem A red light shows that the adj...

Страница 26: ...s built in power meter or an external power meter 3 Reconnect the cable to the clock recovery module 4 Disconnect the cable from the reference receiver module s input connector 5 Measure the signal using a power meter You can use either the Agilent 83480A s built in power meter or an external power meter 6 Subtract the two measurements to determine the insertion loss of the module Insertion loss _...

Страница 27: ...robes have standard attenuation factors such as divide by 10 divide by 20 or divide by 100 Because the following procedures include compensation for insertion loss of the clock recovery module do not perform the procedure To Compensate for Module Insertion Loss on page 2 12 The following probes are available for use with Agilent 83491A clock recovery modules Agilent N1020A TDR probe This passive p...

Страница 28: ...ate probe To compensate an Agilent 54701A active probe 1 Connect the Agilent 83491A output to the electrical measurement channel input 2 Connect the probe to the Input connector on the Agilent 83491A clock recovery module 3 Connect the probe power cable to the Probe Power connector on the reference receiver module 4 Attach the probe tip to the CAL hook that is located near the floppy disk drive 5 ...

Страница 29: ...xternal offset to compensate for the actual characteristics of the device If you do not know the actual charac teristics you can refer to the typical specifications that came with the device 1 Press the reference receiver module s front panel channel SETUP key 2 Press External scale 3 Press Atten units Ratio Attenuation 1 1 and then Units Ampere Volt Watt or Unknown 4 Press Ext gain and enter the ...

Страница 30: ...2 16 Operation Using Probes with an Agilent 83491A book book Page 16 Monday January 7 2002 2 12 PM ...

Страница 31: ... 4 Agilent 83493A Specifications 3 6 Agilent 83494A Specifications 3 7 Agilent 83491 2 3 4A Operating Specifications 3 9 Regulatory Information 3 10 Declaration of Conformity 3 11 Specifications and Regulatory Information book book Page 1 Monday January 7 2002 2 12 PM ...

Страница 32: ...operation Specifications Specifications described warranted performance Characteristics Characteristics provide useful nonwarranted information about the func tions and performance of the instrument Characteristics are printed in italics Calibration cycle Agilent Technologies warrants instrument specifications over the recom mended calibration interval To maintain specifications periodic recalibra...

Страница 33: ...B when measured per TIA EIA OFSTP 4A b Operating power level applies over temperature range 25 C 5 c Better than 10 10 BER when tested with PRBS 223 1 pattern 10 dBm to 3 dBm 10 dBm to 3 dBm Insertion loss through path DC through 2500 MHz 7 dB Output jitter all rates d d Measured on an oscilloscope eye diagram with PRBS 223 1 test pattern 0 0125 UIrms Maximum continuous electrical power before dam...

Страница 34: ...rnal Output 50 to 70 kHz 4 to 5 MHz Clock recovery rates NRZ coding 155 52 Mb s 622 08 Mb s 1062 50 Mb s 1250 Mb s 2125 00 Mb s 2488 32 Mb s 2500 00 Mb s 0 1 0 1 0 1 0 1 0 1 0 1 0 1 Data triggering characteristic 50 Mb s to 2500 Mb s Operating input power level c d 750 nm to 860 nm Triggering operation all rates 10 10 BER all rates e 1000 nm to 1600 nm Triggering operation all rates 10 10 BER all ...

Страница 35: ... terminated with 33 dB return loss Return loss with fully filled 62 5 µm core multimode fiber may be slightly lower c Source extinction ratio 8 2 dB when measured per TIA EIA OFSTP 4A d Operating power level applies over temperature range 25 C 5 e Better than 10 10 BER when tested with PRBS 223 1 pattern f Better than 10 10 BER when tested with PRBS 223 1 pattern g Measured on an oscilloscope eye ...

Страница 36: ... Mb s 0 1 0 1 0 1 0 1 0 1 Data triggering characteristic 50 Mb s to 2500 Mb s Operating input power level b c Triggering operation all rates 10 10 BER all rates d b Source extinction ratio 8 2 dB when measured per TIA EIA OFSTP 4A c Operating power level applies over temperature range 25 C 5 d Better than 10 10 BER when tested with PRBS 223 1 pattern 20 dBm to 3 dBm 17 dBm to 3 dBm Output jitter a...

Страница 37: ... 155 52 Mb s 622 08 Mb s 2488 32 Mb s 2666 06 Mb s Options 106 and 107 9953 00 Mb s Standard 10312 500 Mb s Option 103 10664 228 Mb s Option 106 10709 225316 Mb s Option 107 0 1 0 1 0 1 0 1 0 03 0 03 0 03 0 03 Data triggering characteristic 50 Mb s to 2500 Mb s Operating input power level b c Triggering operation 9953 00 Mb s 10312 500 Mb s 10664 228 Mb s and 10709 225316 Mb s Triggering operation...

Страница 38: ...eristic 2 5 GHz through 10 GHz characteristic 10 dB 8 dB a Tested with FC PC adapter Optical output terminated without 33 dB return loss b Source extinction ratio 8 2 dB when measured per TIA EIA OFSTP 4A c Operating power level applies over temperature range 25 C 5 d Better than 10 10 BER when tested with PRBS 223 1 pattern e Measured on an oscilloscope eye diagram with PRBS 223 1 test pattern Ta...

Страница 39: ...0 C to 55 C 40 C to 70 C Altitude Operating Non operating 4600 m 15 000 ft 15 300 m 50 000 ft Humidity Operating Non operating up to 90 relative humidity at 35 C up to 90 relative humidity at 35 C Net weight approximately 1 2 kg 2 6 lb Shipping weight approximately 2 1 kg 4 6 lb Dimensions H x W x D 131 66 mm x 80 14 mm x 266 9 mm 5 18 in x 3 15 in x 10 5 in Power Requirements Supplied by mainfram...

Страница 40: ...ion Geraeuschemission LpA 70 dB LpA 70 dB Operator position am Arbeitsplatz Normal position normaler Betrieb per ISO 7779 nach DIN 45635 t 19 Notice for Canada Compliance with Canadian EMC Requirements This ISM device complies with Canadian ICES 001 Cet appareil ISM est conforme a la norme NMB du Canada book book Page 10 Monday January 7 2002 2 12 PM ...

Страница 41: ...3 11 Specifications and Regulatory Information Declaration of Conformity Declaration of Conformity book book Page 11 Monday January 7 2002 2 12 PM ...

Страница 42: ...3 12 Specifications and Regulatory Information Declaration of Conformity book book Page 12 Monday January 7 2002 2 12 PM ...

Страница 43: ...y 4 3 Error Messages 4 5 Electrostatic Discharge Information 4 8 Cleaning Connections for Accurate Measurements 4 10 Returning the Instrument for Service 4 20 Agilent Technologies Service Offices 4 23 Reference book book Page 1 Monday January 7 2002 2 12 PM ...

Страница 44: ...S 10 81000AI FC PCa a The FC PC adapter is the standard adapter supplied with the instrument 81000FI D4 81000GI SC 81000KI DIN 81000SI ST 81000VI Biconic 81000WI Dust Covers FC connector 1005 0594 Diamond HMS 10 connector 1005 0593 DIN connector 1005 0595 ST connector 1005 0596 SC connector 1005 0597 book book Page 2 Monday January 7 2002 2 12 PM ...

Страница 45: ...turned on Is the rear panel line switch set to on Will the mainframe power up without the plug in module installed If the mainframe still does not power up refer to the optional Agilent 83480A Agilent 54750A Service Guide or return the mainframe to a qualified service department If the plug in does not operate Is the plug in module firmly seated in the mainframe slot Are the knurled screws at the ...

Страница 46: ... status of the plug in modules is listed near the bottom of the display in the box labeled Plug ins If the model number of the plug in module is listed next to the appropriate slot number then the mainframe has identified the plug in If known is displayed instead of the model number of the plug in module remove and reinsert the plug in module in the same slot If known is still displayed the mainfr...

Страница 47: ...pe of this book Additional error messages are listed in the Agilent 83480A Agilent 54750A User s Guide for the mainframe Memory error occurred in plug in_ Try reinstalling plug in The mainframe could not correctly read the contents of the memory in the plug in Remove and reinstall the plug in module Each time a plug in is installed the mainframe re reads the memory in the plug in module Verify the...

Страница 48: ...ainframe hardware problem Refer to the Agilent 83480A Agilent 54750A Service Guide If a plug in is installed in the slot there is a plug in module hardware problem Return the plug in module to a qualified service department ID error occurred in plug in_ Service is required The information read from the memory of the plug in module does not match the hardware in the plug in module This can be cause...

Страница 49: ...r use with the Agilent 54710A 54720A Plug in is not supported System firmware upgrade is needed The mainframe may need to have the latest operating system firmware installed Options 001 and 002 provide this firmware on a 3 5 inch diskette To load the new firmware follow the instructions provided with the diskette If you do not have the optional diskette contact your local Agilent Technologies serv...

Страница 50: ... work on electronic assemblies should be performed at a static safe work station The following figure shows an example of a static safe work station using two types of ESD protection Conductive table mat and wrist strap combination Conductive floor mat and heel strap combination Figure 4 1 Static safe work station book book Page 8 Monday January 7 2002 2 12 PM ...

Страница 51: ... suggestions may help reduce ESD damage that occurs during testing and servicing operations Personnel should be grounded with a resistor isolated wrist strap before re moving any assembly from the unit Be sure all instruments are properly earth grounded to prevent a buildup of static charge Table 4 1 Static Safe Accessories Agilent Part Number Description 9300 0797 Set includes 3M static control m...

Страница 52: ... that holds the ferrule in position against another identical ferrule Connectors also vary in the polish curve and concentricity of the core within the cladding Mating one style of cable to another requires an adapter Agilent Technologies offers adapters for most instruments to allow testing with many different cables Figure 4 2 on page 4 11 shows the basic components of a typical connectors The s...

Страница 53: ...etween performance reli ability and cost If properly maintained and cleaned this connector can withstand many repeated connections However many instrument specifications require tighter tolerances than most connectors including the FC PC style can deliver These instruments cannot tolerate connectors with the large non concentricities of the fiber common with ceramic style ferrules When tighter ali...

Страница 54: ...connector The nickel silver allows an active centering process that permits the glass fiber to be moved to the desired position This process first stakes the soft nickel silver to fix the fiber in a near center location then uses a post active staking to shift the fiber into the desired position within 0 2 µm This process plus the keyed axis allows very precise core to core alignments This connect...

Страница 55: ... particles or finger oil can have a significant effect on connector performance Where many repeat connections are required use of a connector saver or patch cable is recommended Figure 4 5 shows the end of a clean fiber optic cable The dark circle in the center of the micrograph is the fiber s 125 µm core and cladding which carries the light The surrounding area is the soft nickel silver ferrule F...

Страница 56: ...rmance when making measurements on a fiber optic system Never use metal or sharp objects to clean a connector and never scrape the connector Avoid matching gel and oils Figure 4 5 Clean problem free fiber end and ferrule Figure 4 6 Dirty fiber end and ferrule from poor cleaning book book Page 14 Monday January 7 2002 2 12 PM ...

Страница 57: ...tor gently insert it in as straight a line as possible Tipping and inserting at an angle can scrape material off the inside of the connector or even break the inside sleeve of connectors made with ceramic material When inserting a fiber optic connector into a connector make sure that the fi ber end does not touch the outside of the mating connector or adapter Avoid over tightening connections Unli...

Страница 58: ...to determine connector degradation A smooth polished fiber end should pro duce a good return loss measurement The quality of the polish establishes the difference between the PC physical contact and the Super PC con nectors Most connectors today are physical contact which make glass to glass connections therefore it is critical that the area around the glass core be clean and free of scratches Alt...

Страница 59: ...provide the proper steps for cleaning fiber optic cables and Agilent Technologies universal adapters The initial cleaning using the alcohol as a solvent gently removes any grit and oil If a caked on layer of material is still present this can happen if the beryllium copper sides of the ferrule retainer get scraped and deposited on the end of the fiber during insertion of the cable a second cleanin...

Страница 60: ... or lens paper 4 Clean the fiber end with the swab or lens paper Do not scrub during this initial cleaning because grit can be caught in the swab and become a gouging element 5 Immediately dry the fiber end with a clean dry lint free cotton swab or lens paper 6 Blow across the connector end face from a distance of 6 to 8 inches using filtered dry compressed air Aim the compressed air at a shallow ...

Страница 61: ...t the instrument to different types of fiber optic cables Figure 4 8 Universal adapters 1 Apply isopropyl alcohol to a clean foam swab Cotton swabs can be used as long as no cotton fibers remain after cleaning The foam swabs listed in this section s introduction are small enough to fit into adapters Although foam swabs can leave filmy deposits these deposits are very thin and the risk of other con...

Страница 62: ... repaired under the terms of the warranty or contract the warranty is at the front of this manual If the instrument is no longer under warranty or is not covered by an Agilent Technologies mainte nance plan Agilent Technologies will notify you of the cost of the repair after examining the unit When an instrument is returned to a Agilent Technologies service office for servicing it must be adequate...

Страница 63: ...esult from using packaging materials other than the original materials Never use styrene pellets as packaging material They do not adequately cushion the instrument or prevent it from shifting in the carton They may also cause instrument damage by generating static electricity 3 Pack the instrument in the original shipping containers Original materials are available through any Agilent Technologie...

Страница 64: ...e the pink antistatic Air Cap to reduce static electricity Wrapping the instrument several times in this ma terial will protect the instrument and prevent it from moving in the carton 4 Seal the carton with strong nylon adhesive tape 5 Mark the carton FRAGILE HANDLE WITH CARE 6 Retain copies of all shipping papers book book Page 22 Monday January 7 2002 2 12 PM ...

Страница 65: ... Technologies Service Numbers Austria 01 25125 7171 Belgium 32 2 778 37 71 Brazil 11 7297 8600 China 86 10 6261 3819 Denmark 45 99 12 88 Finland 358 10 855 2360 France 01 69 82 66 66 Germany 0180 524 6330 India 080 34 35788 Italy 39 02 9212 2701 Ireland 01 615 8222 Japan 81 426 56 7832 Korea 82 2 3770 0419 Mexico 5 258 4826 Netherlands 020 547 6463 Norway 22 73 57 59 Russia 7 095 797 3930 Spain 34...

Страница 66: ...book book Page 24 Monday January 7 2002 2 12 PM ...

Страница 67: ...ctor care 4 10 cotton swabs 4 17 customer assistance iii D damaged shipment 1 3 DATA Auxiliary Output connector 2 6 2 7 data rate indicator lights 1 6 data rates 2 2 multiple of 2 11 declaration of conformity iii 3 11 dust caps 4 18 E electrostatic discharge 1 2 4 8 EMC requirements 3 10 error messages 4 5 error performance analyzers use with 2 3 ESD reducing damage caused by ESD 4 9 static safe w...

Страница 68: ...ting 1 4 returning for service 4 20 S safety information iii 1 3 2 4 sales and service offices 4 23 SELECT key 1 5 2 6 serial number 1 3 service 4 20 returning for 4 20 sales and service offices 4 23 shipping procedure 4 20 single mode fiber 2 7 specifications 3 2 Agilent 83491A 3 3 Agilent 83492A 3 4 Agilent 83493A 3 6 Agilent 83494A 3 7 defined 3 2 operating 3 9 temperature range 3 2 swabs 4 17 ...

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