Tektronix OA 5000 Measuring Insertion Loss

Setting the Reference Level

User Reference

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The reference mode has two primary applications:

1. Reading total attenuation(insertion loss)

2. Approximating signalpower

The total attenuationof any attenuator is the sum of the attenuation caused

by the connections(the insertion loss) and the attenuation caused by the

active element. Since the insertionloss is dependent on many factors, it is

hard to determine this valueprecisely. Some of the factors that affect inser-

tion lossare the condition of the connectors, the cleanliness of the connec-

tors, and the mode pattern of the fiber.Nonetheless, you can measure

insertion loss.

Step 1: Connect a stable source toan optical power meter using two

optical cablesthat have been j oinedwith an in-line adapter.

Step 2: Measure the power on a suitable opticalpower meter and

measure the optical power indBm.

Step 3: Disconnect the cables at the in-lineadapter and connect them

to the opticalattenuator (which should be set at minimum attenuation).

Step 4: Measure the resultant power in dBm.

The insertion loss(within the connector uncertainty) is the difference be-

tween the power reading with only the opticalcables and the reading with

the cables plus the attenuator.The insertion loss specification for the

OA 5000 attenuators is ≤2.0 dB. The total attenuationis the insertion loss

plus the attenuation levelshown on the OA 5000. Thus, by setting the refer-

ence level to the valueof the insertion loss and enabling the reference

display mode, the OA5000 can display the total attenuation of the attenua-

tion system.

Measuring InsertionLoss

Contents

Main Page WARRANTY Page ECDeclarationofConformity Page Welcome Page Contents A Quick Tour User Reference Programming Appendices Page List of Figures List of Tables Safety Symbols and Terms Specific Precautions Page Page Page Page Installation CAUTION Removing the OA 5000 A Quick Tour Preset the OA 5000 Storing and Recalling Settings Setting a Reference Value Settings at Power Up Page Page Operator Overview The User Reference Section Operator Overview 2 --- 2 Figure 2-1: OA 5002 Front Panel User Reference Enabling/Disabling Attenuation WARNING Page Setting Attenuation Levels Specifying the Wavele ngth Setting the Attenuation Level Page Page Setting the GPIB Address Page Setting the Reference Level Measuring Insertion Loss Approximating Signal Power Page Storing and Recalling Attenuation Levels Page Page Page Setting Up the Instrument Controllers Using the GPIB Interface GPIB Requirements Setting the GPIB Address Page Command Syntax Clearing the OA 5000 ATT:DB 10 Command and Query Structure Commands Queries Headers in QueryResponses Command Entry Abbreviating Commands Concatenating Commands Message Terminators Argument Types Block Arguments Numeric Arguments Syntax Diagrams Page Commands Common Commands and Queries Device Commands and Queries ADJusting? (Query Only) ALLev? (Query Only) Page BLRN *CAL? (Query Only) *CLS (No Query Form) DESE DISable DISPlay *ESE *ESR? (Query Only) EVEnt? (Query Only) EVMSG? (Query Only) EVQty? (Query Only) FACTORY (No Query Form) HEADer *IDN? (Query Only) *LRN?orSET? *OPC *PSC RECall (No Query Form) REFerence *RST (No Query Form) *SRE *STB? (Query Only) STORe (Store Attenuation) *TST? (Query Only) VERBOSE *WAI (No Query Form) WAVelength Status and Events Registers Status Registers The Standard Event Status Register (SESR) The Status Byte Register (SBR) Enable Registers The Device Event Status Enable Register (DESER) The Event Status Enable Register (ESER) The Service Request Enable Register (SRER) The Enable Registers and the *PSC Command The Output Queue The Event Queue Queues Event Handling Sequence Status and Events Conflicts 3 --- 4 0 Programming Messages Page Page Page Page Page Appendix A: Accessories Standard Accessories Optional Accessories Page Appendix B: Specifications Page Page Page Appendix C: Interface Specifications Interface Messages Page GPIB Function Subsets Page Appendix D: Using the *OPC Query/Command Page Appendix E: Packing for Shipment Page Appendix F: Maintenance Cleaning the Optical Ports Page Changing the Optical Port Connectors Page Page Page Appendix G: Product Verification Equipment List Power Up Display Modes GPIB Address Setting Attenuation Range Shutter Attenuation and the DISABLE button 1310 nm: Page 1550 nm: 850 nm (except OA 5002): Page Appendix H: Replaceable Parts Item Names Parts Ordering Information Using the Replaceable Parts List Indentation System Abbreviations Page AppendixH: Replaceable Parts A --- 3 4 Appendices CROSS INDEX --- MFR. CODE NUMBER TO MANUFACTURER AppendixH: Replaceable Parts OA 5000 Series User Manual A --- 3 5 Page Page Page Index A B C D E F G H N O P Q R T U V W