User, Programming and Service Guide Agilent 11896A Polarization Controller
Notice The information contained in this document is subject to change without notice. Agilent Technologies makes no warranty of any kind with regard to this material, including, but not limited to, the implied warranties of merchantability and tness for a particular purpose. Agilent Technologies shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material.
Certi cation Agilent Technologies certi es that this product met its published speci cations at the time of shipment from the factory. Agilent Technologies further certi es that its calibration measurements are traceable to the United States National Institute of Standards and Technology, to the extent allowed by the Institute's calibration facility, and to the calibration facilities of other International Standards Organization members.
Warranty This Agilent Technologies instrument product is warranted against defects in material and workmanship for a period of one year from date of shipment. During the warranty period, Agilent Technologies will, at its option, either repair or replace products which prove to be defective. For warranty service or repair, this product must be returned to a service facility designated by Agilent Technologies.
Assistance Product maintenance agreements and other customer assistance agreements are available for Agilent Technologies products. For any assistance, contact your nearest Agilent Technologies Service O ce.
Safety Symbols CAUTION WARNING The following safety symbols are used throughout this manual. Familiarize yourself with each of the symbols and its meaning before operating this instrument. The caution sign denotes a hazard to the instrument. It calls attention to a procedure which, if not correctly performed or adhered to, could result in damage to or destruction of the instrument. Do not proceed beyond a caution sign until the indicated conditions are fully understood and met.
General Safety Considerations WARNING WARNING WARNING WARNING Before this instrument is switched on, make sure it has been properly grounded through the protective conductor of the ac power cable to a socket outlet provided with protective earth contact. Any interruption of the protective (grounding) conductor, inside or outside the instrument, or disconnection of the protective earth terminal can result in personal injury.
How to Use This Manual This manual provides information about the Agilent 11896A polarization controller.
Contents 1. General Information Description . . . . . . . . . . . . . . . . . Instrument con guration . . . . . . . . . . Options . . . . . . . . . . . . . . . . Accessories . . . . . . . . . . . . . . . Polarization-dependent loss measurements . . Power meter PDL measurement system . . Swept-wavelength PDL measurement system Max/min PDL measurement system . . . . Theory of Operation . . . . . . . . . . . . . Speci cations and Characteristics . . . . . . . Serial Numbers . . . . . . . . . . . . . . .
Storage . . . . . . . . . Making connections . . . . . Summary . . . . . . . . . Inspection . . . . . . . . Visual inspection . . . . Optical performance testing Introduction . . . . . . Insertion loss . . . . . . Return loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3. Using the Agilent 11896A Polarization Controller Front-Panel Features . . . . . . . . . . . .
Program header options . . . . . . . . . . . . . . Program data syntax rules . . . . . . . . . . . . . . . Numeric program data . . . . . . . . . . . . . . Program message terminator . . . . . . . . . . . . Selecting multiple subsystems . . . . . . . . . . . . Initialization . . . . . . . . . . . . . . . . . . . Programming over GPIB . . . . . . . . . . . . . . . Interface capabilities . . . . . . . . . . . . . . . . Command and data concepts . . . . . . . . . . . . Addressing . . . . . . . . . . . . . . .
:STATus:PRESet . . . . . . . . :STATus:QUEStionable :CONDition . . :STATus:QUEStionable :ENABle . :STATus:QUEStionable :EVENt . . :SYSTem:ERRor . . . . . . . . :SYSTem:VERSion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-31 4-31 4-32 4-32 4-33 4-34 Performing a Veri cation Check . . . . . . . Verify startup . . . . . . . . . . . . . Verify the SCAN RATE function . . . . Verify the LOCAL function . . . . . . .
Regular orders . . . . . . . . . . . . . . . . . Hotline orders . . . . . . . . . . . . . . . . . . . A. Choosing the Scan Rate and Measurement Time Single wavelength PDL measurements . . . . . . . . Swept wavelength PDL measurements . . . . . . . . Depolarization application . . . . . . . . . . . . . B. Measurement Considerations Overall insertion loss . . . . . . . . . . Insertion loss variation with paddle position Optical return loss . . . . . . . . . . . Extinction ratio . . . . . . . . . . . .
Figures 1-1. Typical application setup using the Agilent 11896A polarization controller. . . . . . . . . . . . . . . . 1-2. Setup for single-wavelength PDL measurements using an optical power meter. . . . . . . . . . . . . . . . . 1-3. Setup for swept-wavelength PDL measurements using an optical spectrum analyzer. . . . . . . . . . . . . . 1-4. Example of swept-wavelength PDL test data. . . . . . . . 1-5. Setup for single-wavelength max/min PDL measurements. . 1-6. Example of max/min PDL measurement data.
Tables 1-1. 1-2. 2-1. 2-2. 2-3. 4-1. 4-2. 4-3. 4-4. 4-5. 5-1. 5-2. 5-3. A-1. Performance Speci cations . . . . . . . . . . . . . . . . Static-Safe Accessories . . . . . . . . . . . . . . . . . . Accessories Supplied with the Agilent 11896A . . . . . . . Agilent 11896A Power Requirements . . . . . . . . . . . AC Power Cables Available . . . . . . . . . . . . . . . . Standard Event Status Enable Register . . . . . . . . . . . Standard Event Status Register . . . . . . . . . . . . . .
Contents
1 General Information
General Information What you'll nd in this chapter 1-2 A description of the Agilent 11896A polarization controller. A list of options and accessories available. Agilent 11896A polarization controller speci cations and characteristics. Information about the controller's serial number label. Information about avoiding damage to the controller from electrostatic discharge.
Description The Agilent 11896A polarization controller provides manual and automatic polarization state adjustments over a wide wavelength range (1250 to 1600 nm). All possible states of polarization are achieved with extremely small optical insertion-loss variations (60.002 dB).
General Information Description Instrument con guration The standard Agilent 11896A polarization controller includes: FC/PC front-panel connector interfaces Agilent 11896A User, Programming, and Service Guide Options Accessories The following options are available: Option Description Option 010 Option 025 Deletes FC/PC front-panel connector interfaces. One meter pigtail ber with FC/PC connector interfaces.
General Information Description Polarization-dependent loss measurements Polarization-dependent loss (PDL) measurement systems can be created by combining the Agilent 11896A with instruments like the Agilent 8153A lightwave multimeter, the Agilent 71450A or Agilent 71451A optical spectrum analyzer and the Agilent 8509A/B lightwave polarization analyzer.
General Information Description Swept-wavelength PDL measurement system Figure 1-3 shows how to con gure the Agilent 11896A polarization controller and the Agilent 71451A optical spectrum analyzer for performing automatic swept-wavelength PDL measurements. Figure SWPTWAVE here. Figure 1-3. Setup for swept-wavelength PDL measurements using an optical spectrum analyzer.
General Information Description An example of swept-wavelength PDL test data, showing the amount of PDL simultaneously observed over a broad wavelength spectrum, is shown in Figure 1-4. Figure 1-4. Example of swept-wavelength PDL test data.
General Information Description Max/min PDL measurement system Figure 1-5 shows how to setup the Agilent 11896A polarization controller and the Agilent 8509A/B lightwave polarization analyzer for performing automatic single-wavelength max/min PDL measurements. Figure 1-5. Setup for single-wavelength max/min PDL measurements.
General Information Description An example of max/min PDL measurement data is shown in Figure 1-6. The states of polarization are displayed as Stokes parameters and PDL markers on the Poincare sphere at the points where maximum and minimum power values actually occur during the measurement. Figure 1-6. Example of max/min PDL measurement data.
Theory of Operation Figure 1-7. Agilent 11896A polarization controller block diagram. The transmitted signal enters the polarization controller and passes through the internal four- ber-loop assembly. The dimensions of each loop are optimized to approximate a quarter-wave retarder response over the polarization controller's speci ed wavelength range. Complete and continuous polarization adjustability is achieved by independently adjusting each loop over an angular range of 180 .
Speci cations and Characteristics This section contains speci cations and characteristics for the Agilent 11896A polarization controller. The speci cations in this chapter apply over the temperature range 0 C to +55 C (unless otherwise noted). All speci cations apply after the instrument's temperature has been stabilized after 1 hour continuous operation and self-calibration routines have been run. Fiber pigtail interfaces are assumed for all cases, except where otherwise stated.
General Information Speci cations and Characteristics Table 1-1. Performance Speci cations Performance Speci cations Operating wavelength range Insertion loss Overall insertion loss Variation with paddle position Variation with wavelength (1250{1600 nm) Variation with wavelength (any 100 nm range) Optical return loss Polarization extinction ratio Paddle adjustment 1250 to 1600 nm 1250 to 1600 nm <2.0 dB2 <60.02 dB2 60.3 dB 60.1 dB <1.5 dB3 <60.002 dB3 60.3 dB 60.
General Information Speci cations and Characteristics 1-13
Serial Numbers Agilent Technologies makes frequent improvements to its products to enhance their performance, usability, or reliability, and to control costs. Agilent Technologies service personnel have access to complete records of design changes to each type of equipment, based on the equipment's serial number. Whenever you contact Agilent Technologies about your polarization controller, have the complete serial number available to ensure obtaining the most complete and accurate information possible.
Electrostatic Discharge Information Electrostatic discharge (ESD) can damage or destroy electronic components. All work on electronic assemblies should be performed at a static-safe work station. Figure 1-8 shows an example of a static-safe work station using two types of ESD protection: Conductive table-mat and wrist-strap combination. Conductive oor-mat and heel-strap combination. Both types, when used together, provide a signi cant level of ESD protection.
General Information Electrostatic Discharge Information Figure 1-8. Example of a static-safe work station.
General Information Reducing ESD damage The following suggestions may help reduce ESD damage that occurs during testing and servicing operations. Before connecting any coaxial cable to an instrument connector for the rst time each day, momentarily ground the center and outer conductors of the cable. Personnel should be grounded with a resistor-isolated wrist strap before touching the center pin of any connector and before removing any assembly from the unit.
General Information
2 Installation and Preparation for Use
Installation and Preparation for Use What you'll nd in this chapter 2-2 Preparing the polarization controller for use. Turning on the controller. Making ber optic connections.
Preparing the Polarization Controller for Use Initial inspection Inspect the Agilent 11896A shipping container for damage. If the shipping container or cushioning material is damaged, keep it until you have veri ed that the contents are complete and you have tested the polarization controller mechanically and electrically. Table 2-1 lists the accessories shipped with the polarization controller.
Installation and Preparation for Use Preparing the Polarization Controller for Use Connecting the Agilent 11896A to a power source CAUTION The polarization controller is a portable instrument and requires no physical installation other than connection to a power source. Do not connect ac power until you have veri ed that the line voltage is correct and the proper fuse is installed. Damage to the equipment could result. Power requirements Table 2-2.
Installation and Preparation for Use Preparing the Polarization Controller for Use Figure 2-1. Checking the fuse. Power cable The polarization controller is equipped with a three-wire power cable, in accordance with international safety standards. When connected to an appropriate power line outlet, this cable grounds the instrument cabinet.
Installation and Preparation for Use Preparing the Polarization Controller for Use WARNING Failure to ground the polarization controller properly can result in personal injury. Before turning on the polarization controller, you must connect its protective earth terminals to the protective conductor of the main power cable. Insert the main power cable plug only into a socket outlet that has a protective earth contact.
Installation and Preparation for Use Preparing the Polarization Controller for Use Table 2-3.
Turning on the Agilent 11896A With the power cable inserted into the line module, turn the polarization controller on by rocking the front-panel switch to the \1" position. After a moment, numerals appear on the front-panel LCD. If the LCD fails to light, refer to \Performing a Veri cation Check" in Chapter 5.
Lightwave Connector Care Introduction Lightwave cable interfaces can be damaged by improper cleaning and connection procedures. Dirty or damaged lightwave interfaces can result in nonrepeatable or inaccurate measurements. This section will suggest some best practices to clean, care for, connect, and inspect lightwave connectors. Lightwave connectors are used to connect two ber ends together.
Installation and Preparation for Use Lightwave Connector Care Return loss is another important factor. It is a measure of re ection: the less re ection the better (the larger the return loss, the smaller the re ection). The best physically contacting connectors have return losses better than 40 dB, although 20 to 30 dB is more common.
Installation and Preparation for Use Lightwave Connector Care Cleaning and handling Proper cleaning and handling of lightwave connectors is imperative for achieving accurate and repeatable measurements with your Agilent Technologies lightwave equipment. Lightwave interfaces should be cleaned before each measurement using the techniques described in this handbook. Information on protecting and storing your connectors/cables and tips on how to properly mate connectors are also included in this section.
Installation and Preparation for Use Lightwave Connector Care Cleaning non-lensed lightwave connectors Equipment CAUTION Process CAUTION The following is a list of the items that should be used to clean non-lensed lightwave connectors.
Installation and Preparation for Use Lightwave Connector Care Cleaning lightwave adapters Equipment All of the items listed above for cleaning connectors may be used to clean lightwave adapters. In addition, small foam swabs may be used along with isopropyl alcohol and compressed air to clean the inside of lightwave connector adapters. NOTE As noted in a previous caution statement, the foam swabs can leave lmy deposits.
Installation and Preparation for Use Lightwave Connector Care Storage All of Agilent Technologies' lightwave instruments are shipped with either laser shutter caps or dust caps on the lightwave adapters that come with the instrument. Also, all of the cables that are shipped have covers to protect the cable ends from damage or contamination. These dust caps and protective covers should be kept on the equipment at all times except when in use.
Installation and Preparation for Use Lightwave Connector Care Making connections Proper connection technique requires attention to connector compatibility, insertion technique and torque requirements. Connectors must be the same connector type in order to ensure mechanical and optical compatibility. Attempting to connect incompatible connector types may prevent the connection from functioning properly and even cause damage to the ber surfaces.
Installation and Preparation for Use Lightwave Connector Care Summary When making measurements with lightwave instruments or accessories, the following precautions will help to insure good, reliable, repeatable measurements: Con rm connector type compatibility. Use extreme care in handling all lightwave cables and connectors. Be sure the connector interfaces are clean before making any connections. Use the cleaning methods described in this handbook.
Installation and Preparation for Use Lightwave Connector Care Optical performance testing Introduction Consistent measurements with your lightwave equipment are a good indication that you have good connections. However, you may wish to know the insertion loss and/or return loss of your lightwave cables or accessories.
Installation and Preparation for Use Return loss Return loss can be tested using a number of di erent test equipment con gurations. Some of these are: an Agilent 8703 lightwave component analyzer an Agilent 8702 analyzer with the appropriate source, receiver and lightwave coupler an Agilent 8504 precision re ectometer an Agilent 8153 lightwave multimeter with an Agilent 81543 return loss module Many other possibilities exist.
3 Using the Agilent 11896A Polarization Controller
Using the Agilent 11896A Polarization Controller What you'll nd in this chapter 3-2 Agilent 11896A series front-panel features. Agilent 11896A series rear-panel features. Instructions for manually operating the polarization controller.
Front-Panel Features The front panel of the polarization controller includes three main sections: Polarization adjustment Instrument state Data entry 3-3
Using the Agilent 11896A Polarization Controller Front-Panel Features The front panel includes a display and four knobs for adjusting the paddles. The right-most knob is also used to adjust the scan rate, the SAVE and RECALL register numbers, and the GPIB address when using the front-panel function keys. The Agilent 11896A front panel. 1 2 3 4 5 3-4 Display screen. Used to display paddle positions and instrument settings. Status indicators.
Using the Agilent 11896A Polarization Controller Front-Panel Features Error codes The controller has six error codes that can appear on the front panel twelve digit 7-segment LED display: Error Message Type of Error MOTOR ERROR Error parking the motor. Indicates a stuck paddle, faulty motor and so forth. Execution problem occurred in the SCPI controller such as the memory or a CPU register is corrupted. This message is displayed for 12 seconds and then the instrument will attempt to reboot.
Rear-Panel Features The Agilent 11896A rear panel.
Using the Agilent 11896A Precise manual adjustment of the four paddles in the polarization controller can be made using the front-panel knobs while watching the display. Each paddle can rotate 180 in 1000 discrete steps of 0.18 each. The three-segment display shows the relative step count, where zero corresponds to 0 and 999 corresponds to 180 . Nine save/recall registers enable rapid state of polarization hopping between nine di erent user-set states of polarization (SOP).
Using the Agilent 11896A Polarization Controller Using the Agilent 11896A Power-up function The power switch is located in the lower left-hand corner of the front panel. Turn the polarization controller on by setting the switch to the \1" position. When the polarization controller is turned on: All display segments are lit for approximately one second. The rmware revision number is displayed for approximately one second. All four paddles are set to the middle position (500).
Using the Agilent 11896A Polarization Controller Using the Agilent 11896A To continuously sweep all polarization states To continuously and randomly sweep all polarization states, press 4AUTOSCAN5. The scan time clock is reset to 00:00. This indicates the present scan time has been active 0 minutes, 0 seconds. Polarization scanning is initiated at the current scan rate. The elapsed scan time in minutes and seconds is displayed, along with the current scan rate.
Using the Agilent 11896A Polarization Controller Using the Agilent 11896A To save an instrument state To save the instrument state, press 4SAVE5. The number of the last Save register used is displayed. Use the right-most knob to select the desired register (1{9). To save the current instrument state in the displayed register, press 4ENTER5.
Using the Agilent 11896A Polarization Controller Using the Agilent 11896A To use the Local function When the polarization controller is under remote GPIB control, enable local control by pressing 4LOCAL5. To display or change the GPIB address To display or change the GPIB address, press 4LOCAL5. The current GPIB address is displayed. Use the right-most knob to select the desired address (1{30). To save the currently displayed address, press 4ENTER5.
Using the Agilent 11896A Polarization Controller Using the Agilent 11896A
4 Programming
Programming What you'll nd in this section This section introduces the basics for remote programming of a polarization controller. The programming instructions in this manual conform to the IEEE 488.2 Standard Digital Interface for Programmable Instrumentation. The programming instructions provide the means of remote control. You can perform the following basic operations with a computer and a polarization controller: Set up the instrument. Make measurements.
Programming Using the Agilent 11896A Changing the GPIB address The polarization controller's default (factory set) primary address is 20. NOTE The programming examples for individual commands in this manual are written in HP BASIC 5.0 for an HP 9000 Series 200/300 Controller.
Talking to the Instrument Computers acting as controllers communicate with the instrument by sending and receiving messages over a remote interface. Instructions for programming normally appear as ASCII character strings embedded inside the output statements of a \host" language available on your controller. The input statements of the host language are used to read in responses from the polarization controller.
Program Message Syntax To program the instrument remotely, you must have an understanding of the command format and structure expected by the instrument. The IEEE 488.2 syntax rules govern how individual elements such as headers, separators, program data, and terminators may be grouped together to form complete instructions. Syntax de nitions are also given to show how query responses are formatted. Output command The output command is entirely dependent on the programming language.
Programming Program Message Syntax Instructions Instructions (both commands and queries) normally appear as a string embedded in a statement of your host language, such as BASIC, Pascal, or C. Instructions are composed of two main parts: The header, which speci es the command or query to be sent. The program data, which provide additional information needed to clarify the meaning of the instruction.
Programming Program Message Syntax Program data Program data are used to clarify the meaning of the command or query. They provide necessary information, such as whether a function should be on or o . Each instruction's syntax de nition shows the program data, as well as the values they accept. The section \Program Data Syntax Rules" in this chapter has all of the general rules about acceptable values. When there is more than one data parameter, they are separated by commas (,).
Programming Program Message Syntax Compound command header Compound command headers are a combination of two program mnemonics. The rst mnemonic selects the subsystem, and the second mnemonic selects the function within that subsystem. The mnemonics within the compound message are separated by colons.
Programming Program Message Syntax Duplicate mnemonics Identical function mnemonics can be used for more than one subsystem. For example, the function mnemonic STATus may be used to set bits in either the status operation register or the status questionable register.
Programming Program Message Syntax Query command Command headers immediately followed by a question mark (?) are queries. After receiving a query, the instrument interrogates the requested function and places the answer in its output queue. The answer remains in the output queue until it is read or another command is issued. When read, the answer is transmitted across the bus to the designated listener (typically a controller).
Programming Program Message Syntax Program header options Program headers can be sent using any combination of uppercase or lowercase ASCII characters. Instrument responses, however, are always returned in uppercase. Program command and query headers may be sent in either long form (complete spelling), short form (abbreviated spelling), or any combination of long form and short form.
Programming Program Message Syntax Program data syntax rules Program data is used to convey a variety of types of parameter information related to the command header. At least one space must separate the command header or query header from the program data. Numeric program data Some command headers require program data to be expressed numerically. For example, :PADD:POS requires the desired paddle position range to be expressed numerically.
Programming Program Message Syntax Program message terminator The program instructions within a data message are executed after the program message terminator is received. The terminator may be either an NL (New Line) character, an EOI (End-Or-Identify) asserted in the GPIB interface, or a combination of the two. Asserting the EOI sets the EOI control line low on the last byte of the data message. The NL character is an ASCII linefeed (decimal 10).
Programming Program Message Syntax NOTE Multiple commands may be any combination of compound and simple commands. Initialization To make sure the bus and all appropriate interfaces are in a known state, begin every program with an initialization statement. HP BASIC provides a CLEAR command which clears the interface bu er: CLEAR 720 ! initializes the interface of the instrument When you are using GPIB, CLEAR also resets the polarization controller's parser.
Programming over GPIB This section describes the GPIB interface functions and some general concepts. In general, these functions are de ned by IEEE 488.2. They deal with general interface management issues, as well as messages which can be sent over the interface as interface commands. Interface capabilities The interface capabilities of the polarization controller as de ned by IEEE 488.1, are SH1, AH1, T5, L4, SR1, RL1, PP1, DC1, DT1, C0, and E2.
Programming Programming over GPIB Addressing To allow the instrument to go into remote mode when sent a GPIB command, send the command: ''REMOTE 7'' To place the instrument in remote mode, send the command: ''REMOTE 720'' NOTE There is no way to place the instrument in remote mode from the front-panel. Each device on the GPIB resides at a particular address, 0{30. The active controller speci es which devices talk and which listen.
Programming Programming over GPIB Communicating over the bus (HP 9000 series 200/300 controller) Since GPIB can address multiple devices through the same interface card, the device address passed with the program message must include not only the correct interface select code, but also the correct instrument address. Interface select code (selects interface) Each interface card has a unique interface select code.
Programming Programming over GPIB Lockout To disable front-panel control while a program is running, send the LOCAL LOCKOUT command. The instrument can be returned to local mode by sending the LOCAL command to the instrument. NOTE Cycling the power also restores front-panel control. Bus commands The following commands are IEEE 488.2 bus commands (ATN true). IEEE 488.2 de nes many of the actions which are taken when these commands are received by the instrument.
Programming Common Commands Common commands *CLS (Clear Status) The *CLS (clear status) common command clears the status data structures, including the device-de ned error queue. This command also clears the Request-for-OPC ag. If the *CLS command immediately follows a program message terminator, the output queue and the MAV (message available) bit are cleared.
Programming Common Commands *ESE (Event Status Enable) The *ESE command sets the bits in the Standard Event Status Enable Register. The Standard Event Status Enable Register contains a mask value for the bits to be enabled in the Standard Event Status Register. A one in the Standard Event Status Enable Register enables the corresponding bit in the Standard Event Status Register. A zero disables the bit.
Programming Common Commands *ESR (Event Status Register) The *ESR query returns the contents of the Standard Event Status Register. When you read the Event Status Register, the value returned is the total bit weights of all of the bits that are high at the time you read the byte. Table 4-2 shows each bit in the Event Status Register and its bit weight. Reading the register clears the Event Status Register.
Programming Common Commands *IDN (Identi cation Number) The *IDN query identi es the instrument type and software version by returning the following string: \HEWLETT-PACKARD 11896A 0 " Where: ::= the software revision of the instrument. An *IDN query must be the last query in a message. Any queries after the *IDN query in a program message are ignored. Query Syntax: *IDN? < > Returned Format: HEWLETT-PACKARD,11896A,0,X.
Programming Common Commands *RCL (Recall) The *RCL command restores the state of the instrument from the speci ed save/recall register. An instrument setup must have been stored previously in the speci ed register. *RCL 0 has the same e ect as *RST. Command Syntax: Example: *RST (Reset) f0j1j2j3j4j5j6j7j8j9g OUTPUT 720;\*RCL 3" The *RST command places the instrument in a known state. The instrument is placed in manual mode and all paddles are set to position 500.
Programming Common Commands *SRE (Service Request Enable) The *SRE command sets the bits in the Service Request Enable Register. The Service Request Enable Register contains a mask value for the bits to be enabled in the Status Byte Register. A one in the Service Request Enable Register enables the corresponding bit in the Status Byte Register. A zero disables the bit. Table 4-3 lists the bits in the Service Request Enable Register and what they mask. The *SRE query returns the current value.
Programming Common Commands *STB (Status Byte) The *STB query returns the current value of the instrument's status byte. The MSS (Master Summary Status) bit is reported on bit 6 instead of the RQS (request service) bit. The MSS indicates whether or not the device has at least one reason for requesting service. Refer to Table 4-4 for the meaning of the bits in the status byte. To read the instrument's status byte with RQS reported on bit 6, use the interface Serial Poll.
Programming Common Commands *TST (Test) The *TST query performs a self-test on the instrument. The result of the test is placed in the output queue. A zero indicates the test passed and a non-zero value indicates the test failed. If a test fails, refer to the troubleshooting section of the polarization controller service manual.
Programming Instrument Speci c Commands Instrument speci c commands :ABORt The :ABORt command stops the scanning. The instrument is placed in manual mode and the scan time is set to zero. The :INITiate:IMMediate command must be executed to restart the paddles scanning. Command Syntax: Example: :INITiate:IMMediate :ABORt OUTPUT 720;\:ABOR" The :INITiate:IMMediate command starts the paddles scanning.
Programming Instrument Speci c Commands :PADDle:POSition The :PADDle:POSition command sets the positions of one of the paddles when the instrument is in manual mode. To insure the paddle has reached its nal position, it is best to send either the *WAI or *OPC commands before issuing other commands. If the instrument is scanning, this command generates an error. The default is PADD1. The :POSition query returns the position of a paddle.
Programming Instrument Speci c Commands :SCAN:RATE The :SCAN:RATE command sets the scan rate of the paddles to one of eight possible values. Scan rate \1" is the slowest rate, scan rate \8" is the fastest scan rate. Setting the scan when the instrument is already scanning resets the scan timer. The :SCAN:RATE query returns the current scan rate. Command Syntax: :SCAN:RATE fMAXimum j MINimum j g Where: ::= the desired scan rate.
Programming Instrument Speci c Commands :SCAN:TIMer:CLEar The :SCAN:TIMer:CLEar command resets the scan timer to zero. (The commands *RST, INITiate:IMMediate, ABORT, and SCAN:RATE also reset the scan timer to zero.) Command Syntax: Example: :STATus:OPERation :CONDition :SCAN:TIMer:CLEar OUPUT 720;\:SCAN:TIM:CLE;" The :STATus:OPERation:CONDition query always returns zero for the Agilent 11896A. It is a required command for IEEE 488.2 and is implemented only for completeness.
Programming Instrument Speci c Commands :STATus:OPERation :EVENt The :STATus:OPERation:EVENt query always returns zero for the Agilent 11896A. It is a required command for IEEE 488.2 and is implemented only for completeness. Query Syntax: Example: :STATus:OPEReration:EVENt? OUTPUT 720;\:STAT:OPER:EVEN?" ENTER 720;Result PRINT Result :STATus:PRESet The :STATus:PRESet command presets the SCPI transition lters, the SCPI enable registers, and the SCPI error/event queue enable.
Programming Instrument Speci c Commands :STATus:QUEStionable :ENABle The :STATus:QUEStionable:ENABle command sets the questionable data enable register. The :STATus:QUEStionable:ENABle query returns a decimal value indicating the bits set in the questionable data enable register.
Programming :SYSTem:ERRor The :SYSTEM:ERROR query outputs the next error number in the error queue over the interface. This instrument has an error queue that is 30 errors deep and operates on a rst-in, rst-out basis. Repeatedly sending the query :SYSTEM:ERROR? returns the error numbers in the order they occurred until the queue is empty. Any further queries return zeros until another error occurs. If a string is used for the return variable, the error number and the error message will be returned.
Programming :SYSTem:VERSion The :SYSTem:VERSion query returns the version of SCPI with which this instrument complies.
5 Veri cation and Service Information
Veri cation and Service Information What you'll nd in this chapter 5-2 How to perform a quick veri cation check of the Agilent 11896A lightwave polarization controller. How to verify the Agilent 11896A speci cations. How to return the Agilent 11896A polarization controller for service. How to service the Agilent 11896A polarization controller.
Performing a Veri cation Check To verify the functionality of the Agilent 11896A polarization controller, use the following procedure. Verify startup 1. Turn on the polarization controller by setting the front-panel power switch to the \1" position. 2. Recall register zero (0) by pressing: 4RECALL5 Use the right-hand knob to select register zero (0) and then, press 4ENTER5. The display will initially read: HP 11896A V1.00 (The number following V, is the rmware revision number. The number 1.
Veri cation and Service Information Performing a Veri cation Check Verify the LOCAL function 4. Verify the Local function by pressing: 4LOCAL5 The display will read: HPIB ADDR:11 (The number 11 is used as an example, your display may be di erent.) Turn the right-hand knob. The GPIB address on the display will change over a range of 00 to 30. Verify the SAVE and RECALL functions 5. Verify the Save and Recall functions by pressing: 4RECALL5 Adjust the right-hand knob until \0" is displayed. 6.
Veri cation and Service Information Performing a Veri cation Check 12. Recall the position values in register 1 by pressing: 4RECALL5 Adjust the right-hand knob until \RECALL:1" is displayed. 13. Press 4ENTER5. The display will change to: 500:500:500:500 14. Recall the position values in register 2 by pressing: 4RECALL5 Adjust the right-hand knob until the display reads: ''RECALL:2'' 15. Press 4ENTER5. The display will change to: 510:510:510:510 Verify the event timer 16.
Veri cation and Service Information Performing a Veri cation Check If the veri cation check fails If the Agilent 11896A does not pass the veri cation check, you should review the procedure being performed when the problem occurred. A few minutes spent performing some simple checks may save waiting for your instrument to be repaired. Before calling Agilent Technologies or returning the unit for service, please make the following checks: 1. Is the line fuse good? 2. Does the line socket have power? 3.
Verifying the Agilent 11896A Speci cations To verify the speci cations of the Agilent 11896A polarization controller, use the following procedures. Insertion loss Insertion loss can be tested using a number of di erent test equipment con gurations.
Veri cation and Service Information Verifying the Agilent 11896A Speci cations Return loss Return loss can be tested using a number of di erent test equipment con gurations.
How to Return the Agilent 11896A for Service When an instrument is returned to an Agilent Technologies service o ce for servicing, it must be adequately packaged and have a complete description of the failure symptoms attached. When describing the failure, please be as speci c as possible about the nature of the problem. Include copies of additional failure information (such as instrument failure settings, data related to instrument failure, and error messages) along with the instrument being returned.
Veri cation and Service Information How to Return the Agilent 11896A for Service Instrument shipping preparation procedure 1. Write a complete description of the failure and attach it to the instrument. Include any speci c performance details related to the problem. The following information should be returned with the instrument. Type of service required. Date instrument was returned for repair. Description of the problem: Whether problem is constant or intermittent.
Veri cation and Service Information How to Return the Agilent 11896A for Service CAUTION Inappropriate packaging of instruments may result in damage to the instrument during transit. Wrap the instrument in antistatic plastic to reduce the possibility of damage caused by electrostatic discharge. For instruments weighing less than 54 kg (120 lb), use a double-walled, corrugated cardboard carton of 159 kg (350 lb) test strength.
Veri cation and Service Information How to Return the Agilent 11896A for Service Sales and service o ces Sales and service o ces Agilent Technologies has sales and service o ces located around the world to provide complete support for Agilent Technologies products. To obtain servicing information or to order replacement parts, contact the nearest Agilent Technologies Sales and Service O ce.
Veri cation and Service Information How to Return the Agilent 11896A for Service Table 5-1. Agilent 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.
Service Information What you'll nd in this section This section describes how to service the Agilent 11896A. It contains the following service information: General Information Adjustment Procedure Troubleshooting Replacement Procedures Replaceable Parts General information Serial-number information Whenever you contact Agilent Technologies about your lightwave polarization controller, have the complete serial number and option designation available.
Veri cation and Service Information Service Information WARNING Failure to ground the lightwave polarization controller properly can result in personal injury, as well as instrument damage. Before turning on the lightwave polarization controller, connect a three-wire power cable with a standard IEC 320-C13 (CEE 22-V) inlet plug to the lightwave polarization controller power receptacle. The power cable outlet plug must be inserted into a power-line outlet socket that has a protective earth-contact.
Veri cation and Service Information Service Information Required service tools Table 5-2 lists the tools that may be required to service the Agilent 11896A. Table 5-2. Required Tools Description Agilent Part Number Small Pozidriv screwdriver 8710-0899 Large Pozidriv screwdriver 8710-0900 Wire cutter 8710-0012 Long-nose pliers 8710-0030 5/16-nut driver 8720-0015 3/8-nut driver 8720-0005 5.
Veri cation and Service Information Service Information Replacement procedures This section describes procedures for replacing the assemblies in the Agilent 11896A polarization controller. To replace an assembly: Locate the desired assembly in Figure 5-1. Follow the steps for removing the desired assembly. Replace the assembly. Reassemble the polarization controller by reversing the procedure. When replacing the polarization controller, center the optical connectors with the dress panel holes.
Veri cation and Service Information Service Information To replace the polarization assembly 1. Remove the front-panel assembly as described in \To replace the front-panel assembly". 2. Gently unplug the power supply cable, line voltage cable, and ribbon cables (2) from the polarization assembly. Take care not to bend the pins. 3. Remove the polarization assembly by carefully sliding it up and towards the rear. To replace the power supply 1. 2. 3. 4. 5. To replace the GPIB connector 1. 2. 3. 4.
Veri cation and Service Information Service Information Replaceable parts This section contains information for identifying and ordering replacement assemblies and mechanical parts for the Agilent 11896A lightwave polarization controller. Replaceable parts table format Table 5-3 lists information for each major assembly and for each major mechanical and electrical part that is not part of a major assembly. The following information is listed in Table 5-3: 1. Agilent Technologies part number. 2.
Veri cation and Service Information Service Information Direct mail-order system Within the USA, Agilent Technologies can supply parts through a direct mail-order system. Advantages of using the system are as follows: Direct ordering and shipment from Agilent Technologies. No maximum or minimum on any mail order. (There is a minimum order amount for parts ordered through a local Agilent o ce when the orders require billing and invoicing.) Prepaid transportation.
Veri cation and Service Information Figure 5-1. Agilent 11896A assembly level replaceable parts. Table 5-3.
Veri cation and Service Information
A Choosing the Scan Rate and Measurement Time
Choosing the Scan Rate and Measurement Time Single wavelength PDL measurements When using an optical power meter, the scan rate depends on the averaging time (T) of the instrument. In most applications, the received power is large enough so a short averaging time can be used. This ensures the fastest measurement. For example, the shortest averaging time of the Agilent 8153A lightwave multimeter power sensor is 20 ms.
Choosing the Scan Rate and Measurement Time Table A-1. Selecting Averaging Time, Scan Rate and Measurement Time Optical Power Meter Averaging Time (T) Scan Rate Measurement Time 20 ms 5 10 s 50 ms 4 25 s 100 ms 3 50 s 200 ms 2 100 s Swept wavelength PDL measurements Typical parameters for the Agilent 71451A Option 002, white light source, and Option 003, swept PDL kit (with the Agilent 11896A), are shown below. Sweep times are in the range of 1 to 5 seconds.
Choosing the Scan Rate and Measurement Time Depolarization application When using scan rate 8, the polarization state at the output of the Agilent 11896A is changing fast enough to act as a depolarizer for detectors with a long averaging time. A detector averages over many polarization states during its averaging time and the polarization-dependent responsivity (PDR) of the detector is reduced or eliminated. A detector averaging time of two seconds is su cient to reduce the detector PDR by a factor of ten.
B Measurement Considerations
Measurement Considerations Overall insertion loss On the Agilent 11896A standard and Option 010, insertion loss is limited by the condition and cleanliness of the ber optic connectors. The insertion loss of the Agilent 11896A Option 010 also depends on which connector family is used. The insertion loss of the Agilent 11896A versions having connectors will measure approximately 2.0 dB when using clean, undamaged FC/PC connectors.
Measurement Considerations Insertion loss variation with paddle position When the paddles of the Agilent 11896A are rotated, ber bend losses and polarization dependent losses may result in small changes in insertion loss. On the Agilent 11896A standard and Option 010, the insertion variation is determined almost entirely by the polarization dependent loss (PDL) of the ber optic connector interface.
Measurement Considerations NOTE Even minor damage or contamination to the connector faces will result in a signi cant increase in return loss, therefore return loss is listed in Table 1-1 as a characteristic, non-warranted performance parameter. Extinction ratio The extinction ratio describes the ability of the Agilent 11896A polarization controller to adjust for all states of polarization. A speci c, extreme example is shown in Figure B-1.
Measurement Considerations Paddle angle repeatability Paddle angle repeatability is a measure of the paddles ability to accurately return to a previous physical position. Paddle angle repeatability cannot be used to quantify the state of polarization (SOP) repeatability because a given paddle rotation angle a ects SOP di erently, depending on the input SOP. Settling time Settling time is de ned as the worst-case time for the Agilent 11896A to recall and stabilize at a new set of paddle positions.
Measurement Considerations
Index
Index A B C :ABORt, 4-27 accessories, 1-4, 2-3 ac power cables, 2-6 connection, 2-4 address display/change, 3-11 addressing, 4-16 adjustment procedure, 5-16 Agilent maintenance contract, 5-6 Agilent Technologies Service O ces, 5-12 application setup, 1-3 assembly-level replaceable parts, 5-21 assembly replacement, 5-17 before servicing the Agilent 11896A, 5-6 blue repair tag, 5-10 bus command device clear (DCL), 4-18 interface clear (IFC), 4-18 calibration, recommended interval, 1-11 certi cation informa
connector care, 2-9{14 compatibility, 2-15 insertion technique, 2-15 interface, 2-9 loss, 2-9 continuous sweep of polarization states, 3-9 customer assistance, v D E F data entry keys, 3-4 data mode operation, 4-15 declaration of conformity, 1-13 depolarization application, A-4 description of the Agilent 11896A polarization controller, 1-3 device address, 4-5 device clear (DCL) command, 4-18 dimension speci cations, 1-12 direct mail-order system, 5-20 direct phone-order system, 5-20 display screen, 3-4
G H I L M GPIB changing the address, 4-3 connector replacement, 5-18 display/change address, 3-11 local function, 3-11 rear panel connector, 3-6 handling of connectors/cable ends, 2-11 header types, 4-7 hotline orders, 5-20 humidity, 1-12 *IDN (Identi cation Number), 4-22 initial inspection, 2-3 initialization, 4-14 :INITiate:IMMediate, 4-27 input power, 1-12 insertion loss, 1-12, 2-9, B-2 optical performance, 2-17 paddle position, B-3 veri cation, 5-7 instruction header, 4-6 instructions (command/query)
N O P nominal quarter-wave plates for paddles, B-5 non-operating temperature, 1-12 numeric program data, 4-12 *OPC (Operation Complete), 4-22 operating speci cations, 1-12 optical performance insertion loss, 2-17 return loss, 2-18 optical return loss, 1-12, B-3 options, 1-4 output command, 4-5 output queue, 4-10 packaging materials, 5-9 paddle adjustment, 1-12, 3-7 angle repeatability, B-5 position, B-3{5 :PADDle:POSition, 4-28 parser, 4-14 part ordering information, 5-19 PDL measurement polarization-depe
adjustment, 5-16 replacement, 5-18 power switch, 3-8 program message syntax, 4-5{14 Q R query command, 4-10 query instructions, 4-6 random sweep of polarization states, 3-9 *RCL (Recall), 4-23 rear panel features, 3-6 recall function veri cation, 5-4 recalling an instrument state, 3-10 recall/save registers, 3-7 regular orders, 5-20 regulatory information, 1-13 reliability considerations servicing, 5-15 remote control GPIB, 3-11 remote mode operation, 4-16 remote programming, 3-7 combining commands, 4-8 c
optical, B-3 optical performance, 2-18 veri cation, 5-8 rotation rates for paddles, B-5 *RST (Reset), 4-23 S safety information, 2-5 symbols, vi safety considerations, vii, 1-15 servicing, 5-14 sales and service o ces, 5-12 save function veri cation, 5-4 save/recall registers, 3-7 saving an instrument state, 3-10 *SAV (Save), 4-23 :SCAN:RATE, 4-29 scan rate, A-2{3 setting, 3-9 veri cation, 5-3 :SCAN:TIMer, 4-29 :SCAN:TIMer:CLEar, 4-30 selected device clear (SDC) command, 4-18 serial numbers, 1-14, 5-14 se
states of polarization (SOP), 3-7 Status Byte Register, 4-24{25 status indicators, 3-4 :STATus:OPERation:CONDition, 4-30 :STATus:OPERation:ENABle, 4-30 :STATus:OPERation:EVENt, 4-31 :STATus:PRESet, 4-31 :STATus:QUEStionable:CONDition, 4-31 :STATus:QUEStionable:ENABle, 4-32 :STATus:QUEStionable:EVENt, 4-32 *STB (Status Byte), 4-25 storage of connectors/adapters, 2-14 storage temperature, 1-12 swept-wavelength measurement time, A-3 PDL measurement, 1-6 scan rate, A-3 :SYSTem:ERRor, 4-33 :SYSTem:VERSion, 4-34
