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User Interface Reference

Keysight

N4374B Lightwave Component Analyzer, User’s Guide

The LCA Function Keys

1 If it is not already running, start the LCA server by pressing

, or by clicking the LCA server icon on the

desktop.loading the LCA macros.

a Press the “Macro Setup” button on the front panel of the

network analyzer.

b Select

c Select

d Select

e Press the [Macro Setup] key on the front panel of the

network analyzer.

f Select

•

: Brings the LCA user interface to the

foreground, to setup an LCA measurement.

•

: Perform a single sweep measurement

with the current measurement setup.
Pressing this function key when a single or
continuous measurement is running, stops this
measurement and starts a new, single sweep measurement.

•

: Perform continuous measurement sweeps with the

current measurement setup.
Pressing this function key during a single or continuous
measurement, stops the measurement.

•

: Start the optical power monitor. This uses the

current measurement setup to determine the wavelength and
the optical input for which the average optical power is
measured.

•

: If it is not already running, this starts the LCA

server. If it is already running, it brings the server to the
foreground.

For information on further function keys, please refer to the
documentation supplied with the network analyzer.

Содержание N4374B

Страница 1: ...Keysight N4374B Lightwave Component Analyzer User s Guide ...

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Страница 4: ... ping charges duties and taxes for products returned to Keysight from another country Keysight warrants that its software and firm ware designated by Keysight for use with an instrument will execute its programming instructions when properly installed on that instrument Keysight does not warrant that the operation of the instrument software or firmware will be uninterrupted or error free Limitatio...

Страница 5: ...27 Starting the LCA 27 Accessing the User s Guide 28 Performance Quick Check 29 Preparation 30 Network analyzer settings and electrical calibration 30 Verifying your Electrical Calibration 32 Verifying the Optical Connections and Optical CW Operation 34 Verifying the Electrical Connection and Electro optical Operation 37 Measurement Concepts 41 General Measurement Techniques and Considerations 42 ...

Страница 6: ... Optical Path Deembedding 66 RF Path Deembedding 67 Tools 69 Laser Source 69 Receiver 69 RF Power 70 Reset UI 70 Making Measurements 73 Starting the Lightwave Component Analyzer 74 Calibrating the Network Analyzer before Measurements 75 Measuring Opto Electrical OE Devices 77 Initializing the OE measurement 77 Making single ended OE measurements 82 Measuring Electro Optical EO Devices 83 Initializ...

Страница 7: ...rs 103 Replacing the Fuse 111 Troubleshooting 113 Checking the Operation of the Lightwave Component Analyzer 114 Event Log 115 Reinstalling and Updating the Software 117 Backing Up your LCA Data 118 Reinstalling the LCA Software 119 Updating the LCA software 119 Reinstalling the LCA software 119 Updating the ENA firmware 121 Definition of Terms 123 Definition of Terms 124 Specifications 131 Defini...

Страница 8: ...ical measurements at 1550 nm OO mode 141 Specifications for electrical to electrical measurements EE mode 142 Group delay uncertainty 143 General Characteristics 144 Assembled dimensions H x W x D Option 332 144 Weight 144 Power Requirements 144 Network analyzer 144 Storage temperature range 144 Operating temperature range 144 Humidity 144 Altitude operating 144 Recommended re calibration period 1...

Страница 9: ...Introduction 1 Introduction Documentation 8 General Safety Considerations 9 Optical Test Set Front and Rear Panels 16 ...

Страница 10: ...nalyzer Refer to it for using the network analyzer for electrical to electrical measurements or for the configuration of the network analyzer The documentation for the optical test set and the Lightwave Component Analyzer application Refer to this documentation for information on using the optical test set together with the network analyzer for optical to optical electrical to optical and optical ...

Страница 11: ...n and to maintain the product in a safe condition Safety symbols CAUTION The caution sign denotes a hazard It calls attention to a procedure which if not correctly performed or adhered to could result in damage to or destruction of the product Do not proceed beyond a caution sign until the indicated conditions are fully understood and met WARNING The warning sign denotes a hazard It calls attentio...

Страница 12: ...e Canadian Standards Association WARNING If this product is not used as specified the protection provided by the equipment could be impaired This product must be used in a normal condition in which all means for protection are intact only WARNING No operator serviceable parts inside Refer servicing to qualified service personnel To prevent electrical shock do not remove covers WARNING This is a Sa...

Страница 13: ... the cabinet If the total power dissipated in the cabinet is greater than 800 watts then forced convection must be used CAUTION Install the instrument so that the power switch is readily identifiable and is easily reached by the operator This is the instrument disconnecting device It disconnects the mains circuit from the mains supply before other parts of the instrument Alternatively an externall...

Страница 14: ...rder to meet the requirements of IEC 60825 1 we recommend that you stick the laser safety labels in your language onto a suitable location on the outside of the instrument where they are clearly visible to anyone using the instrument N4374B 100 102 101 102 Laser wavelength range 1310 20 nm 1550 20 nm Laser Type DFB DFB Laser Class according to IEC 60825 1 1M 1M Maximum CW output power of LCAa aCW ...

Страница 15: ...able the laser when there is no fiber attached to the optical output connector The laser is enabled by the software or by pressing the laser switch on the front panel The laser is on when the green LED above the switch is lit The use of the instruments such as microscopes or spectacles with this product will increase the hazard to your eyes The laser module has built in safety circuitry which will...

Страница 16: ...protective earth connection intentionally Do not remove protective covers Operating personnel must not remove instrument covers Component replacement and internal adjustments must be made only by qualified service personnel Instruments that appear damaged or defective should be made inoperative and secured against unintended operation until they can be repaired by qualified service personnel Defec...

Страница 17: ...s that you must not discard this electrical electronic product in domestic household waste Product Category With reference to the equipment types in the WEEE Directive Annex I this product is classed as a Monitoring and Control instrumentation product Do not dispose in domestic household waste To return unwanted products contact your local Keysight office or see http about keysight com en companyi...

Страница 18: ...he network analyzer please refer to the documentation supplied with the network analyzer 1 2 3 4 5 6 7 10 9 8 1 Power switch Turns on the optical test set To turn on the PNA press the PNA s power key 2 Port A Caution Be sure you do not exceed the RF power values and DC levels noted on the front panel of the instrument This is the RF input to the transmitter of the optical test set ...

Страница 19: ...can damage your eyesight Refer to Laser Safety on page 12 for safety instructions This is the output of the optical transmitter of the lightwave component analyzer 5 Optical Input 1 low power Caution Do not apply more than 7 dBm maximum safe average input power This input is the standard optical input to the optical test set for optical powers up to 4 dBm 6 Optical Input 2 high power Caution Do no...

Страница 20: ...measurement setup Perform continuous sweep measurements with the current measurement setup Start the optical power meter Start the LCA server if not already running 9 Network analyzer Port 2 This is an S parameter measurement port of the Network analyzer Depending on the S parameters of the measurement this can be either an RF input or an RF output 10 Network analyzer Port 1 This is an S parameter...

Страница 21: ...lyzer please refer to the documentation supplied with the network analyzer 1 USB The software on the network analyzer uses the USB port to control the optical test set 2 External Input Plug in an external laser source 3 Line power cable connector Plug in your power cable here 4 Line fuse Replace only with same type See Replacing the Fuse on page 111 1 2 3 4 ...

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Страница 23: ...Getting Started 2 Getting Started Unpacking the Lightwave Component Analyzer 22 Setting Up the Lightwave Component Analyzer 24 ...

Страница 24: ... optical adapter 1x 4374B 90A01 Getting started 1x 4373B 90CD1 LCA support CD 1x 1150 7896 Keyboard 1x 1150 7799 Mouse 1x 8121 1242 USB cable 1x E5525 10285 UK6 report 2x 8120 8862 N type male male RF cable 0 5m 1x 9320 6677 RoHS addendum for Photonic accessories 1x 9320 6654 RoHS addendum for Photonic T M products 1x 11852B CFG001 Minimum loss pad Additional option dependent shipping contents 021...

Страница 25: ...wave Component Analyzer User s Guide 23 If anything is missing or defective contact your nearest Keysight Technologies sales office If the shipment was damaged contact the carrier then contact the nearest Keysight Technologies sales office ...

Страница 26: ...Connect the optical patchcord 6 Repeat step 3 to step 5 for the optical input CAUTION The network analyzer and Lightwave Component Analyzer module are assembled as one analyzer unit Lifting this instrument requires two people using proper lifting techniques For the combined weight please consult the specifications General Characteristics on page 144 and the user s documentation for the network ana...

Страница 27: ...ke sure you connect the angled connector to the optical test set Connecting to the optical test set with a straight connector will damage it CAUTION Before you connect any fiber optic cable to the Lightwave Component Analyzer please ensure it has been properly cleaned Fiber optic connectors are easily damaged when connected to dirty or damaged cables and accessories When you use improper cleaning ...

Страница 28: ...s We recommend you use the patchcords supplied to minimize the number of straight connections Using the patchcords also keeps service costs down as the adaptor patchcord can be exchanged easily CAUTION Always use patchcords to connect to your DUT This protects the connectors of the optical test set by minimizing the number of connector changes CAUTION The contact connector on the optical test set ...

Страница 29: ...ng radiation If the Laser output is on the green LED on the front panel of the module is lit If the Laser output is off the green LED on the front panel of the module is unlit Starting the LCA 1 If it is not already running start the LCA server by loading the LCA macros a Press the Macro Setup button on the front panel of the network analyzer b Select c Select d Select If the LCA server is running...

Страница 30: ...htwave Component Analyzer User s Guide Accessing the User s Guide 1 If it is not already started start the LCA as described in Starting the LCA on page 27 2 Press in the LCA user interface to get to the electronic Version of the users guide ...

Страница 31: ...al CW Operation 34 Verifying the Electrical Connection and Electro optical Operation 37 This chapter shows how to Verify the optical and electrical connections to the N4374B Lightwave Component Analyzer Verify the performance of your N4374B Lightwave Component Analyzer Trouble shoot if you think there may be a malfunction Perform an acceptance test ...

Страница 32: ...etwork analyzer for information on cleaning electrical connections For more information on handling using and maintaining the flexible test port cables please refer to the User s and Service Guide Keysight Technologies N4697E F 1 85 mm Flexible Cables for Test Ports available on the Keysight website Network analyzer settings and electrical calibration 1 On the network analyzer make the following s...

Страница 33: ...lectrical calibration as described in Electrical calibration for single ended measurements on page 75 We recommend you use Electronic Calibration Modules for calibrating the Network Analyzer For more information on handling using and maintaining Electronic Calibration Modules please refer to the Reference Guide Keysight Technologies Electronic Calibration Modules available on the Keysight website ...

Страница 34: ...Click 7 Make a corrected measurement with the network analyzer 8 Inspect the results Electrical return loss S11 should be similar to S22 Both curves should be below 20dB over the full measurement range with only low frequency dependence on applied modulation frequency Transmission loss S12 should be similar to S21 Both curves should be within 0 1dB to 0 6dB over the full measurement range with onl...

Страница 35: ...s on the Electronic Calibration Modules and on the Optical Test Set If you need information on cleaning and inspection of RF connectors refer to the Connector Care section in the User s Guide for the network analyzer Perform a new electrical calibration and retest If the problem persists contact Keysight for support ...

Страница 36: ...put 1 7 dBm or input 2 17 dBm Use the FC PC adapter 1005 0256 to connect the straight ends of the optical patchcords together If you have option 022 Making sure the angled connector connects to the optical test set connect the angled angled optical patchcords N4373B 87906 to the optical output and input 1 7 dBm or input 2 17 dBm Use the FC APC adapter 1005 1027 to connect the angled ends of the op...

Страница 37: ...y on the front panel of the network analyszer then select to see 11 Press to start the LCA measurement setup 12 Select the OO measurement tab 13 Set the following parameters If you have option 102 Dual wavelength 1310nm 1550nm set Wavelength to the wavelength at which you are testing your DUTs 1310nm or 1550nm Laser power 2 dBm Optical input input1 7 dBm max or input 2 17 dBm max User Calibration ...

Страница 38: ... off and inspect all optical connectors with a microscope If the connectors on the N4374B Lightwave Component Analyzer seem to be damaged contact Keysight for repair If the connectors on the patchcord seem to be damaged contact Keysight for replacements With an external optical power meter you can verify the output power of the internal laser and the optical connection on the transmitter side If t...

Страница 39: ... the optical test set connect the two straight angled optical patchcords N4373B 87907 to the optical output and input 1 7 dBm or input 2 17 dBm Use the FC PC adapter 1005 0256 to connect the straight ends of the optical patchcords together If you have option 022 Making sure the angled connector connects to the optical test set connect the angled angled optical patchcords N4373B 87906 to the optica...

Страница 40: ...ength 1310nm 1550nm set Wavelength to the value at which you are testing your DUTs 1310nm or 1550nm Laser power 4 dBm Optical input input1 7 dBm max or input 2 17 dBm max User Calibration None 9 Click then 10 Right click the measurement trace and select Autoscale All in the context menu At the end of the measurement there should be a flat trace An ideal trace might look like this ...

Страница 41: ...es Inspect the electrical connectors on the N4374B Lightwave Component Analyzer and the Flexible Cables for Test Ports visually If electrical connectors seems to be damaged contact Keysight for repair or replacement Clean the electrical connectors on the N4374B Lightwave Component Analyzer and the Flexible Cables for Test Ports Perform a new electrical calibration and retest If the problem persist...

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Страница 43: ...al Measurement Techniques and Considerations 42 Signal Relationships in Opto electric Devices 46 Calibration Concept 50 Measuring 75 Ohm devices 52 Triggering Concepts 53 Measuring at Different Wavelengths and with the External Optical Source Input 54 ...

Страница 44: ...onent under test and a very accurate optical or electrical receiver measures the transmitted signal Since characterization over a range of modulation frequencies is required the frequency of modulation is normally swept over the bandwidth of interest Measurements are typically comprised of the appropriate ratio of microwave modulation current or power and lightwave modulation power Pmod Optical Mo...

Страница 45: ...Block Diagram Figure 1 demonstrates the basic concepts of lightwave component analysis An analysis of how various signals are used in the measurement process is found in Signal Relationships in Opto electric Devices on page 46 LW Source LW Receiver OO EE E O O E Display DUT Amp RF OO EO OE or EE ...

Страница 46: ... output optical modulation power Slope responsivity is used to describe how a change in input current produces a change in optical power Graphically this is shown in the figure below An LCA measures input modulating current and output modulation power and displays the ratio of the two in Watts Amp either linearly or in decibels Pout mW Iin mA Responsivity Rs W A ΔPout Iin Δ Rs dB 20log10 Rs W A W ...

Страница 47: ...ptical modulation power and output modulation current and displays the ratio of the two in Amps Watt OO measurements Characteristics of purely optical devices can also be measured In this case both the stimulus and response are modulated light The ratio measurement is simply one of gain or loss versus modulation frequency As the lightwave component analyzer is able to measure amplitude and phase d...

Страница 48: ...ing devices in the lightwave domain This is intended to show the basis on which EO and OE responsivity measurements are defined The figure below is a general representation of a lightwave system showing input and output signals in terms of terminal voltages input and output currents and optical modulation power S parameters are used to describe the transmitted and reflected signal flow within a de...

Страница 49: ... functions of the EO and OE devices are typically defined in terms of responsivities because signals in both the optical and electrical domain are used and optical signals do not lend themselves conveniently to S parameter definitions Initially the input impedance of the EO converter and the output impedance of the OE converter will be assumed to be Z0 thus S11 and S22 are zero and Using the above...

Страница 50: ...mically just as 0 dB represents an S21 of unity or gain of 1 Consequently source responsivity will be expressed in Watts per Amp which in decibels will be related to a conversion efficiency of 1 W A Similarly receiver conversion efficiency will be relative to 1 A W The individual responsivities can now be expressed individually in decibels Rr P Δ P Δ Rs Rs Rr a1 2 Power incident on the E O convert...

Страница 51: ...lity to accurately measure optical modulation power DP0 and modulation current DI1 2 The measurement of modulation current is derived from the system characteristic impedance and a measurement of electrical power The measurement of optical modulation power is based on a standard lightwave receiver whose characteristics are predetermined and known by the LCA Rr dB 20log10 Rr A W A W Rs dB 20log10 P...

Страница 52: ...est port cable connected to Port 2 This establishes the electrical calibration reference planes for the measurements Whenever there are additional electrical adapters or elements required for connecting the device under test these electrical paths can be accounted for by RF path deeembedding see RF Path Deembedding on page 67 The second stage is the calibration of the optical test set This is hand...

Страница 53: ... additional optical adapters or elements connecting to the device under test these optical paths can be accounted for by optical path deeembedding see Optical Path Deembedding on page 66 The systematic responses of these two stages of calibration can then be deembedded yielding the response of the device under test DUT See Signal Relationships in Opto electric Devices on page 46 for more detail ...

Страница 54: ...m environment and adds the minimum loss pad data to the deembedding data for the network analyzer This extends the calibration reference plain to the 75W DUT interface The files delivered with the LCA are typical data for the Keysight 11852B minimum loss pads By default they are located on the network analyzer at D Keysight Data AdapterCharacterization 11852B s2p If you want to use data for your i...

Страница 55: ... a DC power level equal to the selected optical output power of the LCA When the internal light source is not used EO measurement in Default mode the receiver deembedding is setup for a DC power level of 0 0 dBm During measurements started using the LCAsoftware the network analyzer does not respond to any keystrokes on the keypad The only way to stop a measurement during a sweep is to press the Ab...

Страница 56: ...orrection values between the closest internal wavelength and the wavelength you select it is important that you measure the Rx responsivity for every internal wavelength and your additional wavelengths The file LCA_RxCorr csv is located in the directory C Program Files Keysight LCA Table SN where SN is the serial number of the optical test set We do not recommend to change the values in the LCA_Tx...

Страница 57: ...measurements are applied to the transmitter side using the wavelength correction data in the file LCA_TxCorr csv The LCA expects the power value in the Power box to be the optical power at the Optical Output of the LCA test head To set the right power value if you are using an external source 1 Use a short patchcord to connect the Optical Output to the Optical Input 2 Switch to the Tools tab of th...

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Страница 59: ...User Interface Reference 5 User Interface Reference The LCA Function Keys 58 Default and Advanced Measurement Parameters 60 The Measurement Parameters 64 Tools 69 Saving and Loading Setups 61 ...

Страница 60: ...ith the current measurement setup Pressing this function key when a single or continuous measurement is running stops this measurement and starts a new single sweep measurement Perform continuous measurement sweeps with the current measurement setup Pressing this function key during a single or continuous measurement stops the measurement Start the optical power monitor This uses the current measu...

Страница 61: ... sweep This achieves the highest accuracy in EO and OO measurements If you do not need this accuracy you can also start the DUT measurements with the network analyzer s trigger functions In some cases it can become difficult to abort continuous measurements by pressing the Continuous or Single button since the network analyzer does not react to the keypad during measurements If the Sweeping window...

Страница 62: ... parameters for EO OE and OO measurements of devices with a simple stimulus and response path This includes devices like sources receivers or amplifiers Use the advanced parameters for more comprehensive control of your measurements For example to use the optical output as the DC light source to an optical modulator as part of an EO measurement ...

Страница 63: ...urements you are asked to specify the electrical calibration set to be saved with the setup This is the electrical calibration set to be used during user calibration measurements Only a link to the electrical calibration set is saved not the calibration data itself For more details see Measuring Opto Electrical OE Devices on page 77 or Measuring Optical Optical OO Devices on page 88 If User Calibr...

Страница 64: ...A setup The name of the electrical calibration set just used for this user calibration measurement will be saved in the LCA setup Before the LCA saves the setup it asks you whether you want to save the network analyzer state with your LCA setup Loading setups Click to retrieve an existing setup After loading a setup with user calibration mode set to Measure the electrical calibration set specified...

Страница 65: ...er Interface Reference Keysight N4374B Lightwave Component Analyzer User s Guide 63 For more details see Measuring Opto Electrical OE Devices on page 77 or Measuring Optical Optical OO Devices on page 88 ...

Страница 66: ...can enter the wavelength of the external source here This wavelength is used by the optical power meter Power dBm Set the optical output power of the internal laser source If you select to use the optional External Input enter the average optical output power at the LCA transmitter output connector Laser On This control which overrides the default behavior of the Lightwave Component Analyzer is on...

Страница 67: ... uses the factory calibration data only no additional user calibration data is used Measure runs an extra calibration measurement step during the measurement setup Before running the first measurement you need to ensure the instrument has a valid electrical calibration as described in Calibrating the Network Analyzer before Measurements on page 75 At the end of this calibration measurement you can...

Страница 68: ... short and long term signal stability of the modulator working point The pilot tone will affect measurements with IFBW settings of the network analyzer 1 5 kHz For IFBW settings of the network analyzer 3 kHz we recommended you do not use Continuous modulator bias optimization Use Every Sweep or Once instead Forward RF Power dBm Sets the RF power level for the source port Optical Path Deembedding E...

Страница 69: ...00nm Attenuation dB can be used alone or with the values for length and refractive index File lets you use the results of a measurement of the optical path to characterize the source or receiver optical path These results need to be in the form of a 2 port S parameter data files also known as Touchstone s2p data files Only the s21 values of the file are used for correction of the transmission prop...

Страница 70: ... convention of the LCA where any port can be an input or an output these values are directional This means port 1 of the connector is always connected to the network analyzer and port 2 is always connected to the DUT We recommend you use the AdapterChar macro supplied with the network analyzer This includes this directionality in its characterization Please refer to the online help on the Network ...

Страница 71: ...selected on the other tabs Laser Source Source Wavelength nm Set the wavelength of the laser source Power dBm Set the optical output power of the laser source Laser On Select to turn the laser source on Deselect to turn the laser source off External Input The External Input is an optional extra for the Lightwave Component Analyzer Select to use a laser source connected to the External Input on the...

Страница 72: ...source port For balanced measurements on 4 port network analyzers Ports 2 and 3 of the network analyzer are forward for EO measurements and reverse for OE measurements Increasing the forward RF power for OE measurements increases the optical modulation amplitude Reverse RF Power dBm Sets the RF power level for the receiver port We recommend the factory calibrated default value for the best results...

Страница 73: ...User Interface Reference Keysight N4374B Lightwave Component Analyzer User s Guide 71 ...

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Страница 75: ...e Component Analyzer 74 Calibrating the Network Analyzer before Measurements75 Measuring Opto Electrical OE Devices 77 Measuring Electro Optical EO Devices 83 Returning to Electrical Measurements 87 Measuring Optical Optical OO Devices 88 Measuring Optical Power 93 ...

Страница 76: ...l temperature Please refer to Measurement conditions on page 132 for information on settling 3 If it does not start automatically click on the icon on the desktop to start the network analyzer application 4 If it is not already running start the LCA server by pressing or by clicking the LCA server icon on the desktop See The LCA Function Keys on page 58 for information on displaying the LCA functi...

Страница 77: ...eters Keep the following points in mind during network analyzer electrical calibration To get the best S N ratio for your measurements use highest RF power your network analyzer can output without showing a source unlevelled error In many case this is more then the maximum specified output power of the network analyzer Decreasing the IF bandwidth improves the S N ratio of the measurement However d...

Страница 78: ...wave Component Analyzer or return to EE measurement mode as described in Returning to Electrical Measurements on page 87 to calibrate 1 Set your measurement parameters 2 From the Calibration menu select ECAL 3 Select Unknown Thru ON 4 Select 2 Port Cal 5 Optionally you can save the calibration with the instrument state file ...

Страница 79: ...ou must initialise the OE measurement You can see which measurement is currently initialised at the top left of the trace screen If you have already initialised the OE measurement you can connect your device under test and make the measurement by pressing or Please refer to the user guide and online help for the network analyzer for further information Initializing the OE measurement 1 Press 2 Sel...

Страница 80: ...f the modulator working point The pilot tone will affect measurements with IFBW settings of the network analyzer 1 5 kHz For IFBW settings of the network analyzer 3 kHz we recommended you do not use Continuous modulator bias optimization Use Every Sweep or Once instead Not using Continuous modulator bias optimization affects the accuracy of the internal transmitter calibration We recommend you inc...

Страница 81: ...directly If you have already characterized the device and have a s2p file for Deembedding Data select File and enter or select the file For accurate measurements you can also include the optical path in the test circuit without the DUT and select Measure or Load for User Calibration ...

Страница 82: ...ort open and enable the RF Path Deembedding Enter or select the file If you are using a 75 W minimum loss pad enable the RF Path Deembedding and make sure 75 Ohm is selected Enter or select the file with the characterisation of the minimum loss pad 8 Decide what sort of User Calibration you need Normally you do not need extra calibration that is select None The LCA measures to specifications under...

Страница 83: ...Load and select the file from the Windows Explorer window 9 Click to start the measurement preparation If you are performing a user calibration when the following screen is displayed make sure the optical output is connected to the optical input using the patchcord supplied The patchcord has the following part number Single mode angled angled connector N4373 87906 Single mode angled straight conne...

Страница 84: ...tings is selected if you also want to save the complete LCA setup See Saving and Loading Setups on page 61 for more information about LCA setups If you will have no need to reuse or refer to this calibration data click Making single ended OE measurements 1 Connect your device under test 2 When the message is displayed click or to start the measurement 3 To make further measurements with these sett...

Страница 85: ...n for single ended measurements on page 75 Before you make your first electro optical measurement you must initialise the EO measurement You can see which measurement is currently initialised at the top left of the trace screen If you have already initialised the EO measurement you can connect your device under test and make the measurement by pressing or Please refer to the user guide and online ...

Страница 86: ...omponents such as attenuators fiber optic cables or splitters between your device under test and the optical input open and enable Optical Path Deembedding Here you can enter the parameters for the optical path directly If you have already characterized the device and have a s2p file for Deembedding Data select File and enter or select the file ...

Страница 87: ...ters or probe heads between the output port and your device under test open and enable the RF Path Deembedding Enter or select the file If you are using a 75 W minimum loss pad enable the RF Path Deembedding and make sure 75 Ohm is selected Enter or select the file with the characterisation of the minimum loss pad 7 Click to start the measurement preparation ...

Страница 88: ... EO measurements 1 Connect your device under test 2 When the message is displayed click or to start the measurement 3 To make further measurements with these settings press or to start the measurement For information on further parameters please refer to User Interface Reference on page 57 DUT in out ...

Страница 89: ...ore you measure purely electrical devices with the network analyzer you need to initialize EE measurements Initializing the EE Measurement as described here removes all the fixturing information in the network analyzer that is specific to the optical test set 1 Press 2 Make sure the EE Measurement tab is selected 3 Click ...

Страница 90: ...nts see Electrical calibration for single ended measurements on page 75 Before you make your first opto electrical measurement you must initialise the OO measurement You can see which measurement is currently initialised at the top left of the trace screen If you have already initialised the OO measurement you can connect your device under test and make the measurement by pressing or Please refer ...

Страница 91: ...ure to select EverySweep or Continuous for Modulator Optimization Please note optimizing every sweep adds about 1 second to each measurement Continuous optimization uses a pilot tone Measuring with or without the pilot tone may affect your measurement We also recommend if you are using continuous optimization that you also perform a User Calibration The system is calibrated with a default setting ...

Страница 92: ...ainty specified but particularly for improved results at lower frequencies we recommend an extra calibration In this case for User Calibration select Measure If you want to reuse and existing saved calibration for User Calibration select Load and select the file from the Windows Explorer window 9 Click to start the measurement preparation If you are calibrating when the following screen is display...

Страница 93: ...returns to the original electrical calibration for the DUT measurements The currently used calibration is preselected b Select Reduce IFBW for user calibration measurement to reduce noise on the user calibration data The default bandwidth reduction factor is set in the file LCAConfig xml c Click to proceed d When asked whether you want to save the data If you can use this calibration data again cl...

Страница 94: ...asurements 1 Connect your device under test 2 When the message is displayed click or to start the measurement 3 To make further measurements with these settings press or to start the measurement For information on further parameters please refer to User Interface Reference on page 57 DUT in out ...

Страница 95: ...s the most recent measurement setup where this was specified or the input specified on the Tools tab For example if you want to measure the optical power on the high power optical input or at a different wavelength but your last OO measurement used Input 1 you need to 1 Press 2 On the Tools tab in Receiver for Optical Input select Input 2 3 On the Tools tab in Receiver specify the receiver wavelen...

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Страница 97: ... Fuse 111 This system should be serviced only by authorized personnel Using controls or adjustments or performing procedures other than those specified in the documentation supplied with your equipment can result in hazardous radiation exposure WARNING ...

Страница 98: ...trument covers when operating Ensure that the instrument is switched off throughout the cleaning procedures Use of controls or adjustments or performance of procedures other than those specified may result in hazardous radiation exposure Make sure that you disable all sources when you are cleaning any optical interfaces Under no circumstances look into the end of an optical device attached to opti...

Страница 99: ...cleaning recommendations you will discover that they contain several inconsistencies We want to suggest ways to help you clean your various optical devices and thus significantly improve the accuracy and repeatability of your lightwave measurements What do I need for proper cleaning Standard cleaning equipment Before you can start your cleaning procedure you need the following standard equipment D...

Страница 100: ...s Acetone for example will dissolve the epoxy used with fiber optic connectors To avoid damage only use isopropyl alcohol Cotton swabs We recommend that you use swabs such as Q tips or other cotton swabs normally available from local distributors of medical and hygiene products for example a supermarket or a chemist s shop You may be able to obtain various sizes of swab If this is the case select ...

Страница 101: ...o select for cleaning purposes has soft bristles which will not produces scratches The best way to use a pipe cleaner is to push it in and out of the device opening for example when cleaning an interface While you are cleaning you should slowly rotate the pipe cleaner Only use pipe cleaners on connector interfaces or on feedthrough adapters Do not use them on optical head adapters as the center of...

Страница 102: ...ication range about 50X up to 300X A microscope can be found in most photography stores or can be obtained through or specialist mail order companies Special fiber scopes are available from suppliers of splicing equipment Ideally the light source on your microscope should be very flexible This will allow you to examine your device closely and from different angles A microscope helps you to estimat...

Страница 103: ...ng please contact the manufacturer or your sales distributor Premoistened cleaning wipes Use pre moistened cleaning wipes as described in each individual cleaning procedure Cleaning wipes may be used in every instance where a moistened soft tissue or cotton swab is applied Lens cleaning papers Some special lens cleaning papers are not suitable for cleaning optical devices like connectors interface...

Страница 104: ...he fiber as any dust in the cap can scratch or dirty your fiber surface When you have finished cleaning put the dust cap back on or close the shutter cap if the equipment is not going to be used immediately Always keep the caps on the equipment when it is not in use All Keysight Technologies lightwave instruments and accessories are shipped with either laser shutter caps or dust caps If you need a...

Страница 105: ...y large particles Clean the device with a dry cotton swab Use compressed air to blow away any remaining filament left by the swab Heavy dirt If the above procedure is not enough to clean your instrument follow one of the procedures below If you are unsure of how sensitive your device is to cleaning please contact the manufacturer or your sales distributor Do not open the instruments as there is a ...

Страница 106: ...ed light beam you can use an infrared sensor card Hold the card approximately 5 cm from the output of the connector The invisible emitted light is projected onto the card and becomes visible as a small circular spot Preferred procedure Use the following procedure on most occasions 1 Clean the connector by rubbing a new dry cotton swab over the surface using a small circular movement 2 Blow away an...

Страница 107: ...dry pipe cleaner into the opening Rotate the pipe cleaner slowly as you do this 2 Blow away any remaining lint with compressed air Procedure for stubborn dirt Use this procedure when there is greasy dirt on the interface 1 Moisten a new pipe cleaner with isopropyl alcohol 2 Clean the interface by pushing and pulling the pipe cleaner into the opening Rotate the pipe cleaner slowly as you do this 3 ...

Страница 108: ... liquid and mechanical abrasion Take extra care when cleaning lenses with these coatings Lens assemblies consisting of several lenses are not normally sealed Therefore use as little alcohol as possible as it can get between the lenses and in doing so can change the properties of projection Preferred procedure Use the following procedure on most occasions 1 Clean the lens by rubbing a new dry cotto...

Страница 109: ...ment at all times except when your optical device is in use If you do discover filaments or particles the only way to clean a fixed connector interface and the input of the optical block is to use compressed air If there are fluids or oil in the connector please refer the instrument to the skilled personnel of the Keysight service team How to clean instruments with a physical contact interface Rem...

Страница 110: ...pressed air Procedure for stubborn dirt Use this procedure when there is greasy dirt on the interface 1 Moisten a new cotton swab with isopropyl alcohol 2 Clean the interface by rubbing the cotton swab over the surface using a small circular movement 3 Take a new dry soft tissue and remove the alcohol dissolved sediment and dust by rubbing gently over the surface using a small circular movement 4 ...

Страница 111: ...ar movement 3 Take a new dry soft tissue and remove the alcohol dissolved sediment and dust by rubbing gently over the surface using a small circular movement 4 Blow away any remaining lint with compressed air How to clean optical devices which are sensitive to mechanical stress and pressure Some optical devices such as Reference Reflectors are very sensitive to mechanical stress or pressure Do no...

Страница 112: ...d with compressed air If there are any streaks or drying stains on the surface repeat the cleaning procedure How to clean bare fiber ends Bare fiber ends are often used for splices or together with other optical components to create a parallel beam The end of a fiber can often be scratched You make a new cleave To do this 1 Strip off the cladding 2 Take a new soft tissue and moisten it with isopro...

Страница 113: ...the fuse holder from underneath 1 2 Pull the fuse holder and fuse clear of the back panel 3 Take the fuse out of the fuse cap and note the fuse rating 4 Make sure the replacement fuse has the same rating T1A 250V Keysight part number 2110 0007 5 Put the fuse into the fuse holder 6 Put the fuse and fuse cap into the receptacle in the rear of the case and press it into place 1 ...

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Страница 115: ...mponent Analyzer 114 Event Log 115 This system should be serviced only by authorized personnel Using controls or adjustments or performing procedures other than those specified in the documentation supplied with your equipment can result in hazardous radiation exposure WARNING ...

Страница 116: ... as described in the network analyzer user guide and online help 2 Power down both the network analyzer and the optical test set 3 Start the equipment and perform an electrical calibration of the network analyzer as described in Starting the Lightwave Component Analyzer on page 74 4 Perform the performance verification as described in Performance Quick Check on page 29 ...

Страница 117: ...n find this log in the bin subdirectory of the directory where the LCA program is installed If you want to refer to the log save a copy of it before you restart the LCA server The log file is cleared each time the LCA server is restarted If you have a problem with the LCA you can also send the event log file to your Keysight contact person to speed up diagnosis ...

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Страница 119: ...Reinstalling and Updating the Software 9 Reinstalling and Updating the Software Backing Up your LCA Data 118 Reinstalling the LCA Software 119 Updating the ENA firmware 121 ...

Страница 120: ...ta are kept in the Table and Information subdirectories of the directory in which the software is installed These two directories are backed up under the LCA directory on the D drive of your network analyzer These directories are not overwritten when performing the network analyzer s system recovery process Please refer to the user documentation of the network analyzer for information on backing u...

Страница 121: ... screen We recommend you use the default settings Reinstalling the LCA software Pre installing the framework and drivers Before reconnecting the optical test set to the network analyzer that is with the USB cable disconnected or before powering up the optical test set you need to pre install the USB drivers 4 On the CD ROM supplied with the LCA in the directory Reinstallation USB Driver start the ...

Страница 122: ...ctions on the screen We recommend you use the default settings Note the directory to which the LCA application is installed Restoring the hardware calibration files 1 On the network analyzers D drive open the directory LCA 2 Copy all folders with all their subfolders into the LCA installation directory C Program Files Keysight LCA default directory Starting the LCA Server 1 Run the network analyze...

Страница 123: ...ENA firmware To update the ENA firmware please follow the procedure described in the ENA firmware update documentation After updating the ENA firmware you also need to apply a patch to the LCA software Check the LCA support page on the web for these patches Each patch is related to a particular ENA firmware version ...

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Страница 125: ...Definition of Terms 10 Definition of Terms Definition of Terms 124 ...

Страница 126: ...l output Average output power range optical The nominal selectable range for Average output power optical Average output power stability optical The variation of the optical Average output power optical P over time calculated as where maxt and mint are the maximum and minimum value over time t Conditions Time period as specified after modulator auto bias modulator optimization is performed with th...

Страница 127: ...ween measured average over time optical power and true average optical power at the LCA optical input Measurement Comparison with an average power meter with averaging time set to 1 s Average power measurement range optical The range for the average optical power where the specification for Average power measurement uncertainty optical applies Decibel dBm dBo dBe A ratio in decibel dB is calculate...

Страница 128: ...ed measurements of the absolute frequency response under constant conditions the repeatability Rep at each modulation frequency is defined as twice the standard deviation StDevi of the measured responsivities Ri over the repetitions i Conditions fixed cables and unchanged connections Other conditions as specified Measurement using a stable DUT 10log10 R 1A W 2 20log10 R 1A W NOTE Differences of re...

Страница 129: ...hich the system specifications apply Conditions as specified Maximum safe average input power optical Maximum optical power that can be applied to the LCA optical input without permanent change of the LCA s characteristics Minimum measurable frequency response noise floor The average of the Responsivity measured by the LCA on a DUT with zero output expressed in Decibel dBm dBo dBe The value is cal...

Страница 130: ... receiver is designed to supply give measurement results OMI optical modulation index Specifies the Modulated optical power divided by Average output power optical Condition modulation frequency as specified NOTE Responsivity values are converted from Decibel dBm dBo dBe values to linear values by linear 10decibel 20 The average is converted back to decibels by decibel 20 log10 linear Popt t t Pmo...

Страница 131: ...ty specifies the maximum deviation between measured and actual phase difference Measurement Based on a reference RF O E receiver Relative frequency response uncertainty When taking the difference between measured Responsivity of a device under test and actual true responsivity in dBe over modulation frequency the system relative frequency response uncertainty is half the peak to peak difference Co...

Страница 132: ...lated optical power in Watt expressed in A W In both cases responsivity in Decibel dBm dBo dBe dBW A or dBA W is calculated as 20 log R O O measurement R is the difference between the Modulated optical power in dBm at the DUT output and at the DUT input expressed in dBo If expressed in dBe it is twice this number References 1 Guide to the Expression of Uncertainty in Measurement GUM BIPM IEC ISO e...

Страница 133: ...Specifications 11 Specifications Definitions 132 Transmitter and Receiver Specifications 134 General Characteristics 144 ...

Страница 134: ...ues are based on data from a representative set of instruments General characteristics Give additional information for using the instrument These are general descriptive terms that do not imply a level of performance Specifications require an angled connector at the source output and at optical input ports 1 and 2 of the optical receiver Angled contact connectors help you to control return loss Th...

Страница 135: ...ion using an Electronic Calibration Module Keysight 85092C at constant temperature 1 C Modulator bias optimization set to every sweep Measurement frequency grid equals electrical calibration grid DUT signal delay 0 1 IF BW Specified temperature range 20 C to 26 C After warm up time of 90 minutes Using high quality electrical and optical connectors and RF cables in perfect condition Using supplied ...

Страница 136: ...ical input 1 7 dBm Optical input 2 17 dBm Optical return loss typ b 27 dBo Average power measurement rangeb Optical input 1 25 dBm to 4 dBm Optical input 2 15 dBm to 14 dBm Average power measurement uncertainty typ b 0 5 dBo LCA optical output internal source Optical modulation index OMI at 1 GHz typ 30 at 5 dBm RF power Output wavelength Option 100 102 1310 20 nm Option 101 102 1550 20 nm Average...

Страница 137: ...r s Guide 135 a Excluding water absorption wavelength b Wavelength within range as specified for LCA optical output c After modulation optimization d Required source characteristics SMSR 35dB linewidth 10MHz power stability 0 1dB pp PER 20dB unmodulated single mode ...

Страница 138: ... typ Absolute frequency response uncertainty DUT response 18 dB W A a 1 3 dBe typ 2 2 dBe 1 3 dBe typ 2 2 dBe 1 3 dBe typ Frequency response repeatability typ DUT response 38 dB W A a 0 02 dBe 0 02 dBe 0 02 dBe Minimum measurable frequency Response noise floor b c 98 dB W A typ 103 dB W A 103 dB W A Phase uncertainty typ d DUT response 38 dB W A a 1 5 1 5 Group delay uncertainty Derived from phase...

Страница 139: ... typ Absolute frequency response uncertainty DUT response 18 dB W A a 1 3 dBe typ 2 2 dBe 1 3 dBe typ 2 2 dBe 1 3 dBe typ Frequency response repeatability typ DUT response 38 dB W A a 0 02 dBe 0 02 dBe 0 02 dBe Minimum measurable frequency Response noise floor b c 100 dB W A typ 103 dB W A 103 dB W A Phase uncertainty typ d DUT response 38 dB W A a 1 0 1 0 Group delay uncertainty Derived from phas...

Страница 140: ...quency response uncertainty DUT response 36 dB A W b 1 2 dBe typ 1 8 dBe 1 2 dBe typ c 1 8 dBe 1 2 dBe typ c Frequency response repeatability typ a DUT response 46 dB A W b 0 02 dBe 0 02 dBe 0 03 dBe Minimum measurable frequency Response noise floor a d e 83 dB A W typ 92 dB A W 92 dB A W Phase uncertainty typ a f DUT response 36 dB A W b 1 0 1 0 Group delay uncertainty Derived from phase uncertai...

Страница 141: ...quency response uncertainty DUT response 36 dB A W b 1 2 dBe typ 2 0 dBe 1 2 dBe typ c 2 1 dBe 1 2 dBe typ c Frequency response repeatability typ a DUT response 46 dB A W b 0 02 dBe 0 02 dBe 0 03 dBe Minimum measurable frequency Response noise floor a d e 83 dB A W typ 92 dB A W 90 dB A W Phase uncertainty typ a f DUT response 36 dB A W b 1 0 1 0 Group delay uncertainty Derived from phase uncertai...

Страница 142: ...MHz 50 MHz to 0 7 GHz 0 7 GHz to 4 5 GHZ Relative frequency response uncertaintya DUT response 13 dBe 6 5 dBo b 0 25 dBe typ 0 125 dBo typ 0 25 dBe 0 125 dBo 0 25 dBe 0 125 dBo Absolute frequency response uncertaintya DUT response 13 dBe 6 5 dBo b 1 0 dBe typ 0 5 dBo typ 1 0 dBe 0 5 dBo 1 0 dBe 0 5 dBo Frequency response repeatability typ a DUT response 13 dBe 6 5 dBo b 0 02 dBe 0 02 dBe 0 02 dBe ...

Страница 143: ...z 50 MHz to 0 7 GHz 0 7 GHz to 4 5 GHZ Relative frequency response uncertaintya DUT response 13 dBe 6 5 dBo b 0 25 dBe typ 0 125 dBo typ 0 25 dBe 0 125 dBo 0 25 dBe 0 125 dBo Absolute frequency response uncertaintya DUT response 13 dBe 6 5 dBo b 1 0 dBe typ 0 5 dBo typ 1 0 dBe 0 5 dBo 1 0 dBe 0 5 dBo Frequency response repeatability typ a DUT response 13 dBe 6 5 dBo b 0 02 dBe 0 02 dBe 0 02 dBe Mi...

Страница 144: ...ghtwave Component Analyzer User s Guide Specifications for electrical to electrical measurements EE mode All specifications of the E5071C 245 Network Analyzer apply Please see the corresponding Network Analyzer data sheet and User s Guide ...

Страница 145: ...lay uncertainty Is calculated from the specified phase uncertainty and from the aperture for aperture see below Aperture Determined by the frequency span and the number of points per sweep GD Range The maximum group delay is limited to measuring no more than 180 degrees of phase change within the selected aperture see the equation for Group Delay GD s Phase change deg Aperture Hz 360 ΔGD s Phase u...

Страница 146: ... 3 kg 60 2 lbs Packaged product Option 332 47 3 kg 104 3 lbs Power Requirements 90 to 132 VAC or 198 to 264 VAC automatic switched 47 to 63 Hz 2 power cables E5071C max 350 VA Optical test set max 40 VA Network analyzer Option 332 E5071C 245 Storage temperature range 40 C to 70 C Operating temperature range 5 C to 35 C Humidity 15 to 80 relative humidity non condensing Altitude operating 0 2000 m ...

Страница 147: ...aser sources listed above are classified as Class 1M according to IEC 60825 1 2007 All laser sources comply with 21 CFR 1040 10 except for deviations pursuant to Laser Notice No 50 dated 2007 June 24 LCA electrical input Type N f LCA electrical output Type N f LCA optical input 1 9mm single mode angled 1 with Keysight universal adapter LCA optical input 2 9mm single mode angled 1 with Keysight uni...

Страница 148: ...Specifications 146 Keysight N4374B Lightwave Component Analyzer User s Guide Mechanical Outline Drawings dimensions in mm ...

Страница 149: ...Regulatory and Warranty Information 12 Regulatory and Warranty Information Regulatory Information 148 Declaration of Conformity 149 Warranty 150 ...

Страница 150: ... Regulatory Information Compliance with Canadian EMC Requirements This ISM device complies with Canadian ICES 001 Cet appareil ISM est conforme à la norme NMB 001 du Canada Table 1 Notice for Germany Noise Declaration Acoustic Noise Emission LpA 50 dB Operator position Normal operation per ISO 7779 ...

Страница 151: ...374B Lightwave Component Analyzer User s Guide 149 Declaration of Conformity Use any of the following web links to search the latest Declaration of Conformity DoC http www keysight go conformity or http regulations about keysight com DoC search htm ...

Страница 152: ...range of additional expert test and measurement services for your equipment including initial start up assistance onsite education and training as well as design system integration and project management Our repair and calibration services will get your equipment back to you performing like new when promised You will get full value out of your Keysight equipment throughout its lifetime Your equipm...

Страница 153: ...test equipment solutions with confidence www keysight com find mykeysight Keysight Open Keysight Open simplifies the process of connecting and programming test systems to help engineers design validate and manufacture electronic products Keysight offers open connectivity for a broad range of systemready instruments open industry software PC standard I O and global support which are combined to mor...

Страница 154: ...4433 Canada tel 877 894 4414 fax 800 746 4866 China tel 800 810 0189 fax 800 820 2816 Europe tel 31 20 547 2111 Japan tel 81 426 56 7832 fax 81 426 56 7840 Korea tel 080 769 0800 fax 080 769 0900 Latin America tel 305 269 7500 Taiwan tel 0800 047 866 fax 0800 286 331 Other Asia Pacific Countries tel 65 6375 8100 fax 65 6755 0042 Email tm_ap keysight com ...

Страница 155: ...tral Electro optical converters www keysight com find ref Optical test instruments accessories www keysight com comms oct accessories Firmware and driver download www keysight com Technical Support Drivers Firmware Software Keysight photonic discussion forum www keysight com find photonic_forum For Network analyzer related literature please visit Keysight Network Analyzers www keysight com find na...

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Страница 157: ...ion The N4374B consists of an E5071C 245 4 5GHz ENA and an optical test set which is mechanically connected to the ENA To protect your network analyzer investments the Keysight offers the integration of an E5071C ENA with the optical test set ...

Страница 158: ...m source optical test set N4374B 102 1310 nm and 1550 nm source optical test set Configuration Independent Options N4374B 010 Time domain option N4374B 050 External optical source input N4374B 021 Straight connector interface external 0 5 m patch cord N4374B 022 Angled connector interface external 0 5 m patch cord Service and Repair R1280A 1 year return to Keysight warranty extended to 3 or 5 year...

Страница 159: ... 901 Australia New Zealand 8120 4419 8164B 902 Continental Europe 8120 1689 8164B 903 United States 120 V 8120 1378 8164B 906 Switzerland 8120 2104 8164B 912 Denmark 8120 3997 8164B 917 Republic of South Africa and India 8120 4211 8164B 918 Japan 8120 4753 8164B 919 Israel 8120 5182 8164B 922 China 8120 8376 8164B 927 Brazil and Thailand 8120 8871 ...

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Страница 161: ...16 18 electro optical see EO EO measurement 83 initializing 83 making single ended 86 specification 136 137 theory of operation 44 event log 115 F fiber adapters cleaning 105 frequency dependent interference 26 front panel 16 function keys 18 58 fuse 19 replacing 111 G ground see protective earth group delay 143 H humidity 144 I input 1 65 70 input 2 65 70 installing 24 in cabinet 11 power switch ...

Страница 162: ... earth 10 14 R radiation exposure 11 rear panel 19 recycling 15 symbol 10 reinstalling 119 return loss angled connectors 27 RF path deembedding 67 RF port see electrical port ripple 26 S s n ratio 75 safety class 10 serviceable parts 10 setting up see installing shipment contents 22 network analyzer 22 smoothing 75 software reinstalling 119 s parameter theory 46 stepped sweep 75 straight connector...

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Страница 164: ...This information is subject to change without notice Keysight Technologies 2017 Edition 4 0 October 2017 www keysight com ...

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