Keysight Technologies N774 C Series User Manual Download Page 74

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Keysight N774xC Series Multiport Power Meter User’s Guide

User Interface Reference

Reset Network Configuration

The

Configure LAN

tab also allows you to reset all LAN parameters to the

factory default. To do so;
1 Click the

Advance Options

button available on

Configure LAN

tab. The

Advance Network Options

page will appear.

2 Click on the

Reset

button to reset all LAN parameters to the factory

default.

WARNING

Your browser connection to the instrument may be broken after

executing the reset network configuration operation. If so, reconnect

to the instrument using the new hostname or IP address.

Summary of Contents for N774 C Series

Page 1: ...User s Guide Keysight N774xC Series Multiport Power Meter N7744C 4 port Optical Power Meter N7745C 8 port Optical Power Meter ...

Page 2: ...ERMS COVERING THE MATERIAL IN THIS DOCUMENT THAT CONFLICT WITH THESE TERMS THE WARRANTY TERMS IN THE SEPARATE AGREEMENT WILL CONTROL Safety Notices CAUTION A CAUTION notice denotes a hazard It calls attention to an operating procedure practice or the like that if not correctly performed or adhered to could result in damage to the product or loss of important data Do not proceed beyond a CAUTION no...

Page 3: ...ting temperature range The instrument should be protected from temperature extremes and changes in temperature that may cause condensation within it The operating temperature is from 5 C to 40 C The storage temperature is from 40 C to 70 C Before Applying Power Verify that all safety precautions are taken The power cable inlet of the instrument serves as a device to disconnect from the mains in ca...

Page 4: ...adian and United States of America standards respectively The RCM mark is a registered trademark of the Australian Communications and Media Authority The KC mark is the Korean certification mark This equipment is Class A suitable for professional use and is for use in electromagnetic environments outside of the home The recycling symbol indicates the general ease with which the instrument can be r...

Page 5: ...on of Conformity Safety Symbol Description This product complies with WEEE Directive 2002 96 EC marking requirements The affixed label indicates that you must not discard this electrical electronic product in domestic household waste Product Category With reference to the equipment types in WEEE Directive Annex I this product is classed as a Monitoring and Control instrumentation product Do not di...

Page 6: ...6 Keysight N774xC Series Multiport Power Meter User s Guide ...

Page 7: ...nsiderations General Information 14 Operating Environment 15 Handling the Instrument 17 Storage Carrying and Shipment 17 Rack Mount the Instrument 17 2 Getting Started Initial Inspection 20 Initial Inspection 20 Claims and Repackaging 20 Return Shipments to Keysight Technologies 20 Deleting User Data 21 Power Supply Requirements 22 Line Power Requirements 22 N774xC Series of Multiport Power Meters...

Page 8: ...he Keysight N7744 45C Multiport Power Meters 28 Removing Quad adapter Interfaces from the Keysight N7744 45C Multiport Power Meter 29 Electrical Connectors 30 LAN Interface 31 The LAN LED 31 The LAN Reset button 31 USB Interface 32 Powering Up the Instrument 33 Connecting the Instrument 34 Connecting over USB 34 Connecting over LAN 35 N774xC User Interface 38 ...

Page 9: ...k 42 Dynamic range logging mode 43 Frequency Response 43 Linearity 43 Maximum safe input power 44 Minimum averaging time 44 Noise pp dark 44 Noise 2 sigma dark 44 Operating humidity 45 Operating temperature 45 Operating temperature and humidity 45 Polarization dependent responsivity PDR 45 Port separation static 46 Port separation dynamic 46 Power range 46 Range settling time one range step 47 Rel...

Page 10: ...ctrical Offsets Zero 62 How to Choose the Range Mode 63 How to Set the Range 64 How to Set the Averaging Time 64 How to Set Automatic Gain for Averaging Modulated Signals 65 How to Choose the MinMax Function 65 How to Use External Triggers 65 How to Use Auxiliary Functions 67 How to Get Current Instrument Settings 67 How to Identity a Module 68 How to Capture an Image of the Graph 68 How to Save R...

Page 11: ...nce Cleaning Instructions 76 Safety Precautions 76 Why is it important to clean optical devices 76 What materials do I need for proper cleaning 77 General Cleaning Procedure 79 Additional Cleaning Information 80 Firmware Upgrades 81 Requirements 81 Contact Keysight Technologies 82 ...

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Page 13: ...Keysight N774xC Series Multiport Power Meter User s Guide 1 General Operating Considerations General Information 14 Operating Environment 15 Handling the Instrument 17 ...

Page 14: ...er disconnect the power cord either at the rear power inlet or at the AC line power source receptacle One of these must always be accessible If the instrument is in a cabinet it must be disconnected from the line power by the system s line power switch WARNING Ensure the proper usage for the instrument The protection provided by the instrument may be impaired The operator of this instrument is adv...

Page 15: ... can circulate through it freely Operating Position When operating the instrument choose a location that provides at least 75 mm 3 inches of clearance at the rear and at least 25 mm 1 inch of clearance at each side Failure to provide adequate air clearance may result in excessive internal temperature reducing instrument reliability The instrument should not be operated when resting on its rear or ...

Page 16: ...16 Keysight N774xC Series Multiport Power Meter User s Guide 1 General Operating Considerations Figure 1 Operating Position of the Instrument 25 mm 1 inch 25 mm 1 inch 75 mm 3 inches ...

Page 17: ...trument You can mount the instrument in a standard 19 inch rack cabinet using one of two optional kits each of which includes instructions and mounting hardware Depending on whether one or two N77xxC instruments are to be mounted different mounting kits are required N7799C 1CM Rack Mount Kit 1 HU for 2 instruments Includes low profile rails Requires Filler Kit N7799C 0CM for single device See Figu...

Page 18: ...eysight N774xC Series Multiport Power Meter User s Guide 1 General Operating Considerations Figure 2 Instrument s Mounted on a Rack A Single Instrument Mounted on a Rack B Two Instruments Mounted on a Rack ...

Page 19: ...Started Initial Inspection 20 Power Supply Requirements 22 Input and Output Connectors 26 Input and Output Connectors 26 Optical Connections 28 Electrical Connectors 30 LAN Interface 31 Powering Up the Instrument 33 Connecting the Instrument 34 N774xC User Interface 38 ...

Page 20: ...waiting for settlement of the claim against the carrier Return Shipments to Keysight Technologies If the instrument is to be shipped to an Keysight Technologies Sales Service Office attach a tag showing owner return address model number and full serial number and the type of service required The original shipping carton and packing material may be reusable but the Keysight Technologies Sales Servi...

Page 21: ...FRAGILE to encourage careful handling In any correspondence refer to instrument by model number and serial number Deleting User Data If you need to delete all your logged data and user configurations press and hold the LAN Reset button approx 5 sec to reset the instrument and all your logged data and user configurations will be deleted ...

Page 22: ...hree wire power cable When connected to an appropriate AC power receptacle this cable earths the instrument cabinet The power switch allows you to switch between stand by mode and power on mode Figure 3 Power LED on the Front Panel of the Instrument CAUTION Please note that the switch on the front panel of the instrument does not stop the flow of power to the instrument If you need to turn off the...

Page 23: ... 23 Getting Started 2 When the instrument is in stand by mode the Power LED is orange When the instrument is powered on the Power LED is green The AC power requirements are summarized on the rear panel of the instrument Figure 4 AC Power Requirement Markings ...

Page 24: ...is is complemented by the ease of integrating multiple instruments into a single setup with parallel programming over the LAN or USB connections A single N7744C N7745C is only one rack unit high and a half rack unit wide With this new power meter comes the trusted N7740 fiber connectivity concept which is a quadruple adapter with a snap on quick locking mechanism The device to be tested can be con...

Page 25: ...o easy to synchronize with Keysight tunable laser sources to make spectral measurements The functionality for time dependent measurement has been extended with sampling at up to 1 MHz and data logging of up to 1 million samples for each port For further details on its application and key features refer to the product datasheet available on www keysight com ...

Page 26: ...ction provides information on the front and rear panels of N774xC multiport power meters Figure 5 shows the front panel of N7744C 4 port power meter Figure 5 Front Panel of the N7744C 4 port power meter Figure 6 shows the front panel of N7745C 8 port power meter Figure 6 Front Panel of the N7745C 8 port power meter ...

Page 27: ...t N774xC Series Multiport Power Meter User s Guide 27 Getting Started 2 Figure 7 shows the rear panel of N7744 45C series multiport power meter Figure 7 Rear Panel of the N7744 45C series multiport power meter ...

Page 28: ... bare fiber connections to power meters the length of fiber extending from the fiber holder must be carefully adjusted to avoid scratching the power meter optics Optical Inputs Quad Adapter Optical Connectors NOTE Before you attach a quad adapter or fiber you should make sure they are clean This is important for accurate measurements The fibers do not contact the optical inputs all contact with th...

Page 29: ... it clicks securely into place without pressing the release levers Removing Quad adapter Interfaces from the Keysight N7744 45C Multiport Power Meter Figure 9 Removing Quad Adapter Interface 1 Press the release levers on both sides of the quad adapter to release it from the front panel of the power meter 2 You can now remove the optical connectors from the quad adapter NOTE There are release lever...

Page 30: ...wo BNC connectors on the rear panel of your instrument These are the Trigger Out and the Trigger In connectors CAUTION The Trigger In is a TTL input A maximum of 5 V can be applied as an external voltage to this input connector The Trigger Output is a TTL output Do not apply an external voltage to this connector ...

Page 31: ...ument is connected directly to a PC The LAN Reset button This recessed button has two functions Pressing the button briefly invokes a preset of the instrument and restores default measurement settings This is equivalent to the programming command SYSTem PRESet Pressing and holding the button for 5 seconds will reset the LAN parameters to the factory default This includes removing the password This...

Page 32: ...t is a USB device with a USB Type B connector which is available on the rear side of the instrument NOTE It is recommended to use the Keysight IO Libraries Suite to enable instrument communication for a variety of development environments It is available at http keysight com find iolibs USB Type B Connector ...

Page 33: ...owering Up the Instrument When you power on the instrument the LEDs on the front panel show the various stages of the instrument Power LAN Status Yellow Standby mode Searching for LAN Warming Up Green ON Connected with LAN Blinking Green Communicating over LAN USB Red Not connected ...

Page 34: ... on the instrument 2 Connect the PC to the instrument using a USB cable 3 The operating system will detect and display the new instrument as a new drive 4 Double click on this new drive It will show a shortcut to start the user interface 5 Double click on this shortcut This will open the user interface of the instrument in a browser ...

Page 35: ...ning start the Keysight Connection Expert software The Discovery Service automatically discovers LAN instruments on the same subnet as the PC on which the service is running 3 To add LAN instruments to the Connection Expert My Instruments list a Click select LAN Instrument from the context list This opens the list of discovered LAN instruments b Click the check box for each instrument you want to ...

Page 36: ...y add LAN instruments outside of the local subnet a Click select LAN Instrument from the context list This opens the list of discovered LAN instruments b Click the Enter Address tab c Enter the LAN address or host name and select the protocol used to communicate with the instrument d Click OK ...

Page 37: ...Keysight N774xC Series Multiport Power Meter User s Guide 37 Getting Started 2 5 Linux or macOS can use the zeroconf mdns discovery service with tools like Avahi GNU Linux or Bonjour Mac ...

Page 38: ...le of N7745C multiport power meter user interface that displays the instrument s connection settings The below figure is also valid for N7744C multiport power meter Figure 10 N774xC User Interface For details on the N7744 45C user interface and how to use it to control the instrument refer to User Interface Reference on page 51 ...

Page 39: ...ions 42 Data logging capability 42 Drift dark 42 Dynamic range logging mode 43 Frequency Response 43 Linearity 43 Maximum safe input power 44 Minimum averaging time 44 Noise pp dark 44 Noise 2 sigma dark 44 Operating humidity 45 Operating temperature 45 Operating temperature and humidity 45 Polarization dependent responsivity PDR 45 Port separation static 46 Port separation dynamic 46 Power range ...

Page 40: ...ser s Guide 3 Definition of Terms Return loss 47 Specification wavelength range 48 Spectral ripple power meter due to interference 48 Storage conditions 48 Total uncertainty 48 Uncertainty at reference conditions 49 Wavelength range 49 Warm up time 49 ...

Page 41: ...uct performance that is usually met but not guaranteed Typical values are based on data from a representative set of instruments Generally all specifications are valid within the specified temperature range after warm up at the stated operating conditions and measurement settings Operating Conditions The environmental conditions for system operation The system must not be operated outside these co...

Page 42: ...xplicitly subject to variation Data logging capability Maximum number of power readings per port that can be captured during a logging operation Drift dark Specifies the maximum deviation from zero of the measured power with no optical input dark over time excluding Noise pp dark on page 44 power expressed in Watts Measurement From the dark measurement result Pi a polynomial fit Fi is calculated T...

Page 43: ...rift dark on page 42 RSS is calculated in linear units Watts Frequency Response Specifies the frequency fresp up to which the power meter s transfer function is above a defined cutoff level The transfer function is the measured optical amplitude on a modulated sinusoidal optical input divided by the actual amplitude over modulation frequency expressed in dB Conditions Cutoff level as specified Oth...

Page 44: ...on page 42 for the N7744C and the N7745C only Powers expressed in Watts Conditions All ports dark Averaging time as specified Other conditions as specified Measurement As for Drift dark From the measured Pi and the fitted curve Fi the noise curve Ni Pi Fi is calculated The noise N is N maxi Ni mini Ni Noise 2 sigma dark Specifies twice the standard deviation of the measured dark power with zero in...

Page 45: ...mperature range for which the specifications apply if not differently stated The instrument must not be operated outside this range If previously stored beyond this range wait for acclimation before turning on the instrument Operating temperature and humidity The ambient temperature range and humidity range of the tunable laser source for which the specifications apply Polarization dependent respo...

Page 46: ...d Port separation dynamic Specifies the difference between step power input Pstep with positive or negative slope applied to one port and the maximum measured power change Dchng positive or negative on any other port without applied power dark Excluding Noise pp dark see Noise pp dark on page 44 and Drift dark see Drift dark on page 42 Powers expressed in dBm dynamic port separation SD expressed i...

Page 47: ... Relative port to port uncertainty Specifies half the maximum difference between the measured powers of different ports when applying the same stimulus Measured powers expressed in dBm the relative port to port uncertainty U expressed in dB Figure 13 Relative port to port uncertainty Conditions As specified Return loss The ratio between the incident power and the power reflected back from the inst...

Page 48: ...ation SOP Connector as specified Other conditions as specified Measurement Using a laser source without spectral ripple or with known monitored spectral ripple and linewidth 100 MHz and stepping the wavelength over the specified range The periodic part in the measurement result is separated by subtracting the polynomial 2nd order fit low frequency part Storage conditions Allowed temperature and hu...

Page 49: ...n the calibration chain from the national calibration laboratory to the test meter expressed in percent Powers expressed in Watts U 100 M P 1 Conditions Reference conditions as specified Wavelength range The range of wavelengths for which the power meter is calibrated or that can be set at the attenuator and for which the specifications apply if not differently stated Warm up time Time after power...

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Page 51: ...Keysight N774xC Series Multiport Power Meter User s Guide 4 User Interface Reference N774xC Series User Interface 52 Controlling N774xC Instruments 54 How to Use Auxiliary Functions 67 ...

Page 52: ...rious tabs that help the user to control the N7744 45C instruments Home This tab displays the various instrument settings For details refer How to Get Current Instrument Settings on page 67 Control Instrument This tab allows you to set the parameters to control the instrument For details refer to Controlling N774xC Instruments on page 54 Get Image This tab allows you to capture a screen of the Con...

Page 53: ... settings For details refer to How to Save Recall the User Interface Settings on page 68 Configure LAN This tab displays the current LAN configuration of the instrument In addition this tab also allows you to edit the current LAN configuration of the instrument For details refer to How to Configure LAN on page 72 Help This tab opens the instrument s help ...

Page 54: ...s that the user interface will show the measured power of all available 4 or 8 channels depending upon the N774xC instrument type The blue highlighted region on the channel scale denotes the measured power level The following image shows the N7745C interface displaying measured power of 8 channels The Control Instrument tab also allows you to configure an individual channel To do so click on the c...

Page 55: ...e 4 Display Wavelength and Power Displays the instrument s current power wavelength and power unit of the selected channel For further details on power and it s unit refer to How to Measure Power on page 58 For further details on wavelength refer to How to Set the Wavelength on page 59 ...

Page 56: ...the power unit 1 Click on the wavelength button 2 Use the left or right arrows to move the position of the cursor pointer to the either left or right 3 Use the up or down arrows to increase or decrease the wavelength 4 Click on the unit button to change the unit The allowed units for Power are W dBm or dB Power Vs Time Graph The Control Instrument tab displays a graph that shows the relationship b...

Page 57: ...n time interval Start Stop Graph Measurement You can start or stop the graph measurement at any point of time To do so go to Settings and then click on the Start Stop toggle button By default this option is enabled However once you disable this button you will notice that the measurements in the graph are stopped until it is enabled Exporting Measurement Results You can export the numerical measur...

Page 58: ...igured to wait for external software or hardware triggers How to Set the Power Unit The Power Unit setting allows you to select either W dBm or dB as the units in which power is displayed or returned For returning large amounts of logged data the fastest data transfer is achieved using W units What are the Power Units The SI unit for power measurement is Watt W You can also measure power in dB or ...

Page 59: ...g is not critical There are two ways to set the wavelength value You can set the wavelength directly on clicking the Wavelength button see Display Wavelength and Power on page 55 or You go the Settings Measurement Settings and then set the wavelength How to Set the Calibration Offset This is a calibration offset that you can enter to compensate for external optical circuitry for example an attenua...

Page 60: ...selected the following equations are used to calculate the power level in dB or where PdB is the returned relative power Pmeasured is the absolute power level see How to Set the Calibration Offset on page 59 and REF is the reference level How to Set the Reference Value to the Current Power Value In addition to entering a new reference value you can change the reference value to the current power v...

Page 61: ...channel s current power level If you choose this mode the reference of the channel continuously updates to the current power value measured by the other channel The following equations describe how the power in dB is calculated if you reference another channel or where PdB is the relative power PmeasuredA is the absolute power level see How to Set the Calibration Offset on page 59 measured by the ...

Page 62: ...rage electrical offset level for the current environmental conditions For the best results you must Allow the instrument time to acclimatize around 24 hours Allow the instrument time to warm up around 20 minutes Make sure that the optical input is not receiving any light or use the zeroing adapter If you are using multi mode fiber optic cable you must disconnect the cable and cover the input to th...

Page 63: ... light or the Power Meter receives ambient light because the input connector is uncovered When zeroing is finished the busy display stops You can now proceed with your measurements When environmental conditions are stable the zero setting will remain valid over long times and the same settings will be active after rebooting the instrument How to Choose the Range Mode You can choose either of two r...

Page 64: ...ws the upper power limit at the available power ranges The lowest measurable power in each range is determined by the noise level which depends on the range setting and the averaging time How to Set the Averaging Time This is the length of time over which a signal is averaged to produce a measured value Longer averaging times increase the accuracy and improve the noise rejection The averaging time...

Page 65: ...ected channel Note that this measurement is independent from the graphical plot The difference between these values delta P is returned in place of P the power value This mode is intended principally for polarization dependent measurements but can be used for other types of measurement Reset MinMax Use this option to reset the minimum value measured and the maximum value measured How to Use Extern...

Page 66: ...ts the function and if LOOP is not 1 then multiple functions will be performed without waiting for further triggers Threshold THR The input trigger allows to specify the minimum maximum threshold values along with the threshold units and pre trigger value 4 Set the output trigger functions The power meter ports can be configured individually to generate output triggers for the following events Dis...

Page 67: ...s tab displays the following settings Description Displays the instrument description such as instrument s model no serial no firmware version and description of the current instrument VISA Instrument Address Displays VISA instrument addresses of the current instrument LAN Details Displays LAN configuration details of the current instrument NOTE Please note that the Home tab does not allows the us...

Page 68: ...ification indicator available on the N774xC Home tab The Status LED on the front panel of the connected module will start flashing How to Capture an Image of the Graph The Get Image tab on the N774xC user interface allows you to capture the current screen of the Control Instrument tab and save it as a PNG image How to Save Recall the User Interface Settings The Save Recall tab on the N774xC user i...

Page 69: ...e target file and click Open The settings will be loaded in the instrument Logging In Out of the N774xC User Interface The login screen allows the authorized users to control the N774xC instruments When the users type in their password and click Enter their credentials are validated and if correct they are logged in If you want to create a new password or change an existing password click on Chang...

Page 70: ...ssword the default password is blank 3 Enter the new password 4 Click the Change Password button The password will be changed Use the new password for logging in to the N774xC web page What If You Forget Your Password If you forget your password please follow the instructions to reset the LAN button See The The LAN Reset button on page 31 Update Rate and Data Points You can use the Update Rate and...

Page 71: ...ent settings 3 Click on Save button Reboot Device A firmware reboot is required if it becomes unresponsive or returns errors To perform a reboot 1 Go to Settings and click Reboot A Reboot Device dialog will appear 2 Click on the Reboot System button This action will restart the firmware and take at least 30 seconds Please wait until the reboot process is completed NOTE The new refresh rates will o...

Page 72: ... displays the currently used LAN settings It display the following networking parameters IP address configuration IP address Subnet mask Default gateway DNS server s Hostname Domain Edit LAN Settings The Configure LAN tab also allows you to edit the currently used LAN settings To do so 1 Click on the Edit button The Edit Network Configuration page will appear as shown in the figure below ...

Page 73: ...may be broken after executing either of the operations below If so reconnect to the instrument using the new hostname or IP address NOTE For IP address and DNS server configuration you can select the Use Automatic Configuration check box to automatically select the IP address and DNS server NOTE It can take up to 30 seconds for changes to these settings to take effect You may need to refresh the C...

Page 74: ...default To do so 1 Click the Advance Options button available on Configure LAN tab The Advance Network Options page will appear 2 Click on the Reset button to reset all LAN parameters to the factory default WARNING Your browser connection to the instrument may be broken after executing the reset network configuration operation If so reconnect to the instrument using the new hostname or IP address ...

Page 75: ...Keysight N774xC Series Multiport Power Meter User s Guide 5 Maintenance Cleaning Instructions 76 Additional Cleaning Information 80 Firmware Upgrades 81 Contact Keysight Technologies 82 ...

Page 76: ...ing procedures To prevent electrical shock disconnect the instrument from the 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 After cleaning do not switch on the instrument when there is no termination to the optical output connector to the optical fiber or to the attached device The laser radiation is no...

Page 77: ...ollowing standard equipment Dust and shutter caps Isopropyl alcohol Cotton swabs Soft tissues Compressed air Dust and shutter caps All of Keysight Technologies lightwave instruments are delivered with either laser shutter caps or dust caps on the lightwave adapter All cables come with covers to protect the cable ends from damage or contamination We suggest these protected coverings should be kept ...

Page 78: ...o much pressure may scratch the surface and could cause your device to become misaligned It is advisable to rub gently over the surface using only a small circular movement Swabs should be used straight out of the packet and never used twice This is because dust and dirt in the atmosphere or from a first cleaning may collect on your swab and scratch the surface of your optical device Soft tissues ...

Page 79: ...o clean the instrument housing Do not open the instruments as there is a danger of electric shock or electrostatic discharge Opening the instrument can cause damage to sensitive components and in addition your warranty will be voided General Cleaning Procedure Light dirt If you just want to clean away light dirt observe the following procedure for all devices Use compressed air to blow away large ...

Page 80: ...Power Meter User s Guide 5 Maintenance Additional Cleaning Information For additional information on cleaning and safety matters for optical devices refer the following document https literature cdn keysight com litweb pdf 5989 4473EN pdf ...

Page 81: ...firmware for the N774xC multiport power meters instruments you require a PC running Windows 10 on it To update the firmware you need to download the current firmware which consist of two components Firmware Upload Utility The latest firmware version bin file CAUTION Ensure to execute the firmware update procedure only under conditions of reliable power and I O connectivity to the instrument For ex...

Page 82: ...y the firmware update file on your local PC After the firmware has been updated the instrument will automatically restart itself with the new software During the update process the Status and the Active LED will flash periodically 4 Check the firmware version Go to instrument s user interface Home tab and check for the firmware version Contact Keysight Technologies To locate a sales or service off...

Page 83: ......

Page 84: ...This information is subject to change without notice Keysight Technologies 2020 Edition 1 1 July 2020 www keysight com ...

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