Safety Symbols Safety Symbols The following safety symbols are used throughout this manual. Familiarize yourself with each of the symbols and its meaning before operating this instru- ment. C A U T I O N 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.
HP 86120A simultaneously measures multiple laser lines, you can characterize wavelength-division-multiplexed (WDM) systems and the multiple lines of Fabry-Perot lasers. Characterize laser lines easily With the HP 86120A you can quickly and easily measure any of the following parameters: • Peak wavelength and power • Average wavelength •...
Page 5
The HP 86120A’s front-panel INPUT connector is no exception. When you use improper cleaning and handling techniques, you risk expensive instrument repairs, damaged cables, and compromised measurements. Before you connect any fiber-optic cable to the HP 86120A, refer to “Cleaning Connec- tions for Accurate Measurements” on page 2-38.
General Safety Considerations General Safety Considerations This product has been designed and tested in accordance with IEC Publica- tion 1010, Safety Requirements for Electronic Measuring Apparatus, and has been supplied in a safe condition. The instruction documentation contains information and warnings which must be followed by the user to ensure safe operation and to maintain the product in a safe condition.
Printing History Printing History HP Part Number Edition Date 86120-90001 First March 1996 Typographical Conventions The following conventions are used in this book. Formatting Information key type Keys or text located on the keyboard or instrument. softkey type Key names that are displayed on the instrument’s screen.
Warranty Warranty This Hewlett-Packard instrument product is warranted against defects in material and workmanship for a period of one year from date of shipment. During the warranty period, Hewlett-Packard Company 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 Hewlett-Packard.
Step 2. Check the Fuse 1-6 Step 3. Connect the Line-Power Cable 1-7 Step 4. Connect a Printer 1-9 Step 5. Turn on the HP 86120A 1-10 Step 6. Enter Your Elevation 1-12 Step 7. Select Medium for Wavelength Values 1-13 Step 8.
Page 14
Getting Started Getting Started The instructions in this chapter show you how to install your HP 86120A. You should be able to finish these procedures in about ten to twenty minutes. After you’ve completed this chapter, continue with Chapter 2, “Making Mea- surements”.
Page 15
The HP 86120A’s front-panel INPUT connector is no exception. When you use improper cleaning and handling techniques, you risk expensive instrument repairs, damaged cables, and compromised measurements. Before you connect any fiber-optic cable to the HP 86120A, refer to “Cleaning Connec- tions for Accurate Measurements” on page 2-38.
If your shipment is damaged or incomplete, save the packing materials and notify both the shipping carrier and the nearest Hewlett-Packard sales and Service office. HP will arrange for repair or replacement of damaged or incomplete shipments without waiting for a settlement from the transportation company.
Page 17
Getting Started Step 1. Inspect the Shipment Table 1-1. Options and Accessories Available for the HP 86120A Item Quantity HP Part Number Option 010 Delete FC/PC connector — — Option 022 Replace flat physical contact interface with — — angled physical contact interface...
3. Use a small flat-blade screwdriver to open the pull-out fuse drawer. 4. Verify that the value of the line-voltage fuse in the pull-out drawer is correct. The recommended fuse is an IEC 127 5×20 mm, 6.3A, 250 V, HP part number 2110-0703.
Getting Started Step 3. Connect the Line-Power Cable Step 3. Connect the Line-Power Cable W A R N I N G This is a Safety Class 1 Product (provided with a protective earthing ground incorporated in the power cord). The mains plug shall only be inserted in a socket outlet provided with a protective earth contact.
Page 20
HP 86120A can be used while sitting on its rear feet. You can order additional ac power cables for use in different geographic areas. Refer to “AC Line-Power...
Step 4. Connect a Printer Step 4. Connect a Printer The HP 86120A can print hardcopies of measurement results on a printer. The output is ASCII text. If you don’t have a printer, continue with “Step 5. Turn on the HP 86120A” on page 1-10.
The front-panel LINE switch disconnects the mains circuits from the mains supply after the EMC filters and before other parts of the instrument. 2. If the HP 86120A fails to turn on properly, consider the following possibilities: • Is the line fuse good? •...
Page 23
When the instrument is first turned on, the display briefly shows the instrument’s firm- ware version number. In the unlikely event that you have a problem with the HP 86120A, you may need to indicate this number when communicating with Hewlett Packard.
Getting Started Step 6. Enter Your Elevation Step 6. Enter Your Elevation In order for your HP 86120A to accurately measure wavelengths and meet its published specifications, you must enter the elevation where you will be per- forming your measurements.
Step 7. Select Medium for Wavelength Values Step 7. Select Medium for Wavelength Values Because wavelength varies with the material that the light passes through, the HP 86120A offers wavelength measurements in two mediums: vacuum and standard air. 1. Press the Setup key.
Getting Started Step 8. Turn Off Wavelength Limiting Step 8. Turn Off Wavelength Limiting After the Preset key is pressed, the input wavelength range is limited to mea- suring lasers between 1200 nm and 1650 nm. You can easily expand the input range to the full 700 nm to 1650 nm range with the following steps: 1.
Hewlett-Packard service office. For a list of offices, refer to “Hewlett-Packard Sales and Service Offices” on page 7-20. If the instrument is still under warranty or is covered by an HP maintenance contract, it will be repaired under the terms of the warranty or contract (the warranty is at the front of this manual).
Getting Started Returning the Instrument for Service Preparing the instrument for shipping 1. Write a complete description of the failure and attach it to the instrument. Include any specific performance details related to the problem. The following information should be returned with the instrument. •...
Page 29
Getting Started Returning the Instrument for Service corrugated cardboard carton of 159 kg (350 lb) test strength. • The carton must be large enough to allow 3 to 4 inches on all sides of the instrument for packing material, and strong enough to accommodate the weight of the instrument.
Page 30
Getting Started Returning the Instrument for Service 1-18...
Page 32
• +10 dBm maximum total displayed input power • Laser linewidths assumed to be less than 10 GHz • If you change the elevation where you will be using your HP 86120A, refer to “Calibrating Measurements” on page 2-34. • Press the green Preset key to return the HP 86120A to its default state.
Page 33
Making Measurements Making Measurements &RQWHQWV# Measuring Wavelength and Power 2-4 To display peak wavelength and power 2-8 To display multiple laser lines 2-8 To display average wavelength and total power 2-8 To use the full wavelength range 2-9 To control the power bar 2-9 Changing the Units and Measurement Rate 2-10 To change the units of measure 2-11 To select single measurement acquisition 2-11...
The figure on this page shows the peak wavelength mode. The figure on the next page shows the list-by-wavelength display mode where the signals are displayed in order from shortest to longest wavelengths. In either mode, the HP 86120A can measure up to 100 laser lines simultaneously. Display after “Peak WL” key pressed...
Page 35
Making Measurements Measuring Wavelength and Power Peak WL mode displays one signal When Peak WL is pressed, the display shows the largest amplitude line in the spectrum. The word PEAK is shown on the screen. If multiple laser lines are present at the input, the number of lines located will be shown along the right side of the screen.
Page 36
Total power and average wavelength can be measured In the third available display mode, the HP 86120A displays the average wave- length as shown in the following figure. The displayed power level is the total input power to the instrument. It is the sum of the powers of each laser line; it is not a measure of the average power level of the laser lines.
Page 37
Spurious signals below 1200 nm may be displayed whenever low-power laser lines (power levels near the HP 86120A’s specified sensitivity) are present at the input. For example, a low-power laser line at 1550 nm has a second har- monic line at 775 nm.
Page 38
Making Measurements Measuring Wavelength and Power To display peak wavelength and power 1. Connect the fiber-optic cable to the front-panel OPTICAL INPUT connector. 2. To display the peak wavelength and power, do one of the following: • Press the green Preset key. •...
Page 39
Making Measurements Measuring Wavelength and Power To use the full wavelength range 1. Press the Setup key. 2. Press MORE and then WL LIM. 3. Press LIM OFF to remove the limits on wavelength range. All responses in the full 700 nm to 1650 nm range are now displayed. To control the power bar 1.
However, should a faster update be desired, for example when real-time feedback is required to tune a laser to its designated channel, the HP 86120A can be set to update approximately four times per second. This reduces both wavelength resolution and accuracy but can be beneficial in some applications.
Making Measurements Changing the Units and Measurement Rate You can specify that the instrument perform a measurement only when the front-panel Single key is pressed. This is the single-acquisition measurement mode, and it is useful for capturing and preserving data. After capturing the data, you can display it using many of the procedures included in this chapter.
Page 42
Making Measurements Changing the Units and Measurement Rate To increase measurement speed 1. Press the Setup key. 2. Press the UPDATE softkey. 3. Select either NORMAL or FAST. 2-12...
Defining Laser-Line Peaks Defining Laser-Line Peaks The HP 86120A uses two rules to identify valid laser-line peaks. Understand- ing these rules is essential to getting the most from your measurements. For example, these rules allow you to “hide” AM modulation sidebands or locate laser lines with small amplitudes.
Page 44
Making Measurements Defining Laser-Line Peaks Peak excursion The peak excursion defines the rise and fall in amplitude that must take place in order for a laser line to be recognized. The rise and fall can be out of the noise, or in the case of two closely spaced signals, out of the filter skirts of the adjacent signal.
Page 45
Limiting the input wavelength range The HP 86120A’s preset condition limits the wavelength measurement range from 1200 nm to 1650 nm. You can expand the wavelength range to cover the entire 700 nm to 1650 nm range. Although wavelength range limiting reduces...
Page 46
Pressing the green PRESET key changes the peak excursion and peak threshold values to their default settings. It also turns wavelength range limiting on. Turning the HP 86120A’s power off and then on does not change these set- tings. 2-16...
Page 47
Making Measurements Defining Laser-Line Peaks If too many lines are identified If the following message is displayed, too many laser lines have been identified: E15 MAX NUMBER OF SIGNALS FOUND The maximum number of laser lines that the instrument can measure is 100. If this mes- sage appears, decrease the peak threshold value or increase the peak excursion value.
This is especially true in wavelength-division- multiplexed (WDM) systems where channel spacing must be adhered to. The HP 86120A can display the wavelength and amplitude of any laser line relative to another. In fact, the following types of relative measurements can be made compared to the reference: •...
Page 49
Making Measurements Measuring Laser Separation The HP 86120A displays separation on this spectrum as shown in the follow- ing figure. Notice that the 1541.747 nm laser line is selected as the reference. It is shown in absolute units. The wavelengths and powers of the remaining responses are shown relative to this reference.
Page 50
Making Measurements Measuring Laser Separation To measure channel separation 1. Press the front-panel Preset key. 2. Press List by WL. 3. Press the Delta On key. Use the Off key to turn off the measurement. 4. Select the type of separation to observe: •...
Measuring Laser Drift Measuring Laser Drift In this section, you’ll learn how the HP 86120A can be used to monitor drift (changes to a laser’s wavelength and amplitude over time). Drift is measured simultaneously for every laser line that is identified at the input. The HP 86120A keeps track of each laser line’s initial, current, minimum, and max-...
Page 52
Making Measurements Measuring Laser Drift If measurement updating stops or the values become blanked If, in the middle of a measurement, the number of laser lines present changes, the mea- surement stops until the original number of lines returns. You’ll notice that a CLEAR soft- key appears and one of the following message is displayed: E46 NUM LINES <...
Page 53
Making Measurements Measuring Laser Drift To measure drift 1. Press the front-panel Preset key. 2. Press Peak WL, List by WL, or List by Power to select the display style for observing drift. 3. Press Appl’s and then DRIFT. Pressing DRIFT sets the current laser-line values as the reference from which to compare all drift.
Page 54
Making Measurements Measuring Laser Drift or minimum values. To restart the drift measurements, press RESET. This resets the reference values. 2-24...
Signal-to-noise measurements are especially important in WDM sys- tems because there is a direct relation between signal-to-noise and bit error rate. The HP 86120A displays signal-to-noise measurements in the third col- umn. For example, the selected signal in the following figure has a signal-to- noise ratio of 23.4 dB/nm.
Page 56
Location of noise measurements Automatic interpolation When the signal-to-noise “auto” function is selected, the HP 86120A first determines the proximity of any adjacent signal. If the next closest signal is ≤200 GHz (approximately 1.6 nm at 1550 nm) away from the signal of interest, then the noise power is measured half way between the two channels and an equal distance to the other side of the signal of interest.
Page 57
PRBS data and SONET formats, there is significant low-frequency ampli- tude modulation of the laser. This modulation raises the noise floor of the HP 86120A significantly. The signal-to-noise measured can be limited to about 15 dB while measur- ing lasers modulated by repetitive data formats.
Page 58
Making Measurements Measuring Signal-to-Noise Ratios To measure signal-to-noise 1. Press the front-panel Preset key. 2. Press List by WL. 3. Press Appl’s and then S/N. 4. To select the wavelength reference for measuring the noise, do the following steps: a. Press WL REF, and •...
Measuring Coherence Length Coherence length is a measure of the distance over which a laser’s light retains the phase relationships of its spectrum. The HP 86120A measures coherence length of Fabry-Perot semiconductor diode lasers. The HP 86120A cannot measure coherence length of light emitting diodes (LEDs) or distributed feed- back (DFB) lasers.
Page 60
Making Measurements Measuring Coherence Length The amplitudes of the peaks decreases exponentially from the largest peak at zero path delay. The exponential decay constant is defined as the coherence length, Lc. The curve that connects the tops of the envelope peaks is given by the following equation: –...
Page 61
Making Measurements Measuring Coherence Length The smaller the alpha factor, the shorter the coherence length. Alpha factor ----- - Beta factor The beta factor is defined as the height of the fringe visibility envelope mid- way between the zero optical path delay peak and the next peak relative to the height of the envelope peak at zero path delay.
Making Measurements Measuring Modulated Lasers Measuring Modulated Lasers A laser that is amplitude modulated at low frequencies (for example, modu- lated in the audio frequency range) can cause spurious wavelengths to be dis- played below and above the correct wavelength. The power of these spurious wavelengths is below that of the correct wavelength.
Measuring Total Power Greater than 10 dBm Measuring Total Power Greater than 10 dBm The maximum total power that can be measured by the HP 86120A is 10 dBm. However, with the addition of an external attenuator, more power can be applied.
Because all measurements made inside the HP 86120A are performed in air, the density of air, due to elevation, affects the wavelength results. You must calibrate the HP 86120A by entering the elevation. Elevations from 0 to 5000 meters can be entered. The elevation correction is immediately applied to the current measurement even if the instrument is in the single measurement acquisition mode.
Page 65
Entries jump in 500 meter steps from 0 m to 5000 m. In order for the HP 86120A to meet its published specifications, the eleva- tion value selected with the softkeys must be within 250 meters of the ac- tual elevation.
(up to 100). The measurement values printed depend on the settings of the instrument when the Print key is pressed. The following is an example of a typical printout: HP 86120A SER US36151025 Firmware Ver. 1.000 List By Wavelength 8 Lines Power Offset 0.0 dB...
Page 67
Making Measurements Printing Measurement Results To create a hardcopy 1. Connect the printer to the HP 86120A’s rear-panel PARALLEL PRINTER PORT connector. 2. Press Print. You can use the ABORT and CONT softkey to stop and restart a print job that is in progress.
Use dry connections. Dry connectors are easier to clean and to keep clean. Dry connections can be used with physically contacting connectors (for exam- ple, Diamond HMS-10/HP, FC/PC, DIN, and ST). If a dry connection has 40 dB return loss or better, making a wet connection will probably not improve (and can degrade) performance.
Page 69
Making Measurements Cleaning Connections for Accurate Measurements Table 2-2. Cleaning Accessories Item HP Part Number Isopropyl alcohol 8500-5344 Cotton swabs 8520-0023 Small foam swabs 9300-1223 Compressed dust remover (non-residue) 8500-5262 Table 2-3. Dust Caps Provided with Lightwave Instruments Item HP Part Number...
Page 70
Making Measurements Cleaning Connections for Accurate Measurements Visual inspection of fiber ends Although it is not necessary, visual inspection of fiber ends can be helpful. Contamina- tion or imperfections on the cable end face can be detected as well as cracks or chips in the fiber itself.
Page 71
To test insertion loss and return loss To test insertion loss, use an appropriate lightwave source and a compatible lightwave receiver to test insertion loss. Examples of test equipment configu- rations include the following equipment: • HP 71450B/51B/52B optical spectrum analyzers with Option 002 built-in 2-41...
Page 72
• HP 8702 analyzer with the appropriate source, receiver, and lightwave cou- pler • HP 8504 precision reflectometer • HP 8153 lightwave multimeter with a source and power sensor module in conjunction with a lightwave coupler • HP 81554SM dual source and HP 81534A return loss module...
Page 74
Programming Programming Programming This chapter explains how to program the HP 86120A. The programming syn- tax conforms to the IEEE 488.2 Standard Digital Interface for Programmable Instrumentation and to the Standard Commands for Programmable Instru- ments (SCPI). Where to begin…...
Page 75
Programming Programming &RQWHQWV Addressing and Initializing the Instrument 3-4 To change the HP-IB address 3-5 Making Measurements 3-6 Commands are grouped in subsystems 3-8 Measurement instructions give quick results 3-10 The format of returned data 3-15 Monitoring the Instrument 3-16...
Addressing and Initializing the Instrument Addressing and Initializing the Instrument The HP 86120A’s HP-IB address is configured at the factory to a value of 20. You must set the output and input functions of your programming language to send the commands to this address. You can change the HP-IB address from the front panel as described in “To change the HP-IB address”...
Page 77
Pressing the green Preset key does not change the HP-IB address. Set single acquisition mode An advantage of using the *RST command is that it sets the HP 86120A into the single measurement acquisition mode. Because the READ and MEASure data queries expect this mode, their proper operation is ensured.
Making measurements remotely involves changing the HP 86120A’s settings, performing a measurement, and then returning the data to the computer. The simplified block diagram of the HP 86120A shown here lists some of the avail- able programming commands. Each command is placed next to the instru- ment section it configures or queries data from.
Page 79
But, because only 8,192 data values are collected in fast-update measure- ment mode, the ability to resolve closely spaced signals is reduced. After collecting the uncorrected data, the HP 86120A searches the data for the first 100 peak responses. (Searching starts at 1700 nm and progresses towards 700 nm).
Programming Making Measurements Commands are grouped in subsystems The HP 86120A commands are grouped in the following subsystems. You’ll find a description of each command in Chapter 4, “Programming Commands”. Subsystem Purpose of Commands Measurement Instructions Perform frequency, wavelength, wavenumber, and coherence length measurements.
Page 81
Programming Making Measurements 7DEOH 6041 &RPPDQGV#IRU#&DSWXULQJ#'DWD Desired Command to Configure Measurement Command to Query Data Measurement (partial listing) Wavelength (nm) CONFigure, FETCh, READ, and MEASure MEASure:ARRay:POWer:WAVelength? Frequency (THz) CONFigure, FETCh, READ, and MEASure MEASure:ARRay:POWer:FREQuency? –1 CONFigure, FETCh, READ, and MEASure MEASure:ARRay:POWer:WNUMber? Wavenumber (m Coherence Length (m)
This is equivalent to using the NORMAL and FAST softkeys. :MEASure command MEASure configures the HP 86120A, captures new data, and queries the data all in one step. For example, to measure the longest wavelength, send the fol-...
Page 83
Programming Making Measurements Specifying SCALar places the display in the single wavelength format and returns a single value to the computer. Specifying ARRay places the display in the List by Power or List by WL modes; an array of data is returned to the com- puter.
Page 84
Programming Making Measurements In the example above, the data in the power and wavelength arrays are returned in the same order so that powers can be matched to wavelengths. Also, because new data is not collected, FETCh is especially useful when char- acterizing transient data.
Page 85
According to the SCPI command reference, ARRay command causes an instrument to take multiple measurements. (A <size> parameter indicates the number of measure- ments to take.) However, the HP 86120A’s ARRay command refers to the measurements performed for one measurement sweep; this results in an array of measured signals.
Page 86
Programming Making Measurements For example, suppose that you wanted to set the elevation correction value and then send an :INIT:IMM command. The following programming fragment results in an error –213 “Init ignored”. This occurs because the :ELEVation command causes the recalculation of the data which is like sending the :INIT:IMM command.
Making Measurements The format of returned data Measurements are returned as strings All measurement values are returned from the HP 86120A as ASCII strings. When an array is returned, the individual values are separated by the comma character. Determine the number of data points...
Monitoring the Instrument Monitoring the Instrument Almost every program that you write will need to monitor the HP 86120A for its operating status. This includes querying execution or command errors and determining whether or not measurements have been completed. Several sta- tus registers and queues are provided to accomplish these tasks.
Programming Monitoring the Instrument Status registers The HP 86120A provides four registers which you can query to monitor the instrument’s condition. These registers allow you to determine the following items: • Status of an operation • Availability of the measured data •...
Page 90
Programming Monitoring the Instrument 3-18...
Page 91
Monitoring the Instrument The Status Byte Register can be read using either the *STB? common com- mand or the HP-IB serial poll command. Both commands return the decimal- weighted sum of all set bits in the register. The difference between the two methods is that the serial poll command reads bit 6 as the Request Service (RQS) bit and clears the bit which clears the SRQ interrupt.
Page 92
Programming Monitoring the Instrument Table 3-4. Bits in Questionable Status Register Definition 0, 1, and 2 not used POWer - indicating that the instrument is measuring too high of a power. 3 through 8 not used Maximum signals - indicating that the instrument has found the maximum number of signals.
Page 93
Programming Monitoring the Instrument Enabling register bits with masks Several masks are available which you can use to enable or disable individual bits in each register. For example, you can disable the Hardcopy bit in the OPERation Status Register so that even though it goes high, it can never set the summary bit in the status byte high.
Page 94
This summary bit sets the MAV bit (bit 4) in the Status Byte Register. The method used to read the Output Queue depends upon the programming language and environment. For example, with HP Basic, the output queue may be read using the ENTER statement.
HP 86120A command strings. For more detailed information regarding the HP-IB, the IEEE 488.2 standard, or the SCPI standard, refer to the following books: Hewlett-Packard Company. Tutorial Description of Hewlett-Packard In- terface Bus, 1987.
Page 96
Programming Reviewing SCPI Syntax Rules SCPI command are grouped in subsytems In accordance with IEEE 488.2, the instrument’s commands are grouped into “subsystems.” Commands in each subsystem perform similar tasks. The fol- lowing subsystems are provided: Measurement Instructions Calculate1 Subsystem Calculate2 Subsystem Calculate3 Subsystem Display Subsystem...
Page 97
Programming Reviewing SCPI Syntax Rules The mnemonic is the first four characters of the keyword unless the fourth character is a vowel, in which case the mnemonic is the first three char- acters of the keyword. This rule is not used if the length of the keyword is exactly four characters. Table 3-5.
Page 98
Programming Reviewing SCPI Syntax Rules Sending common commands If a subsystem has been selected and a common command is received by the instrument, the instrument remains in the selected subsystem. For example, if the program message ”DISPLAY:MARK:MAX:LEFT;*CLS;DISP:MARK:MAX:RIGH” is received by the instrument, the Display subsystem remains selected. If some other type of command is received within a program message, you must reenter the original subsystem after the command.
Page 99
Programming Reviewing SCPI Syntax Rules If a measurement cannot be made, no response is given and an error is placed into the error queue. For example, *RST FETCh:POW? will timeout the controller and place a Data stale or corrupt error ino the error queue.
Page 100
The answer remains in the output queue until it is read or another command is issued. For example, the query OUTPUT 720;”:CALCULATE2:POINTS?” places the number of points in the data set in the output queue. In HP BASIC, the controller input statement: ENTER 720;Range passes the value across the bus to the controller and places it in the variable Range.
Example 5. Measure signal-to-noise ratio 3-42 Example 6. Increase a source’s wavelength accuracy 3-44 These programs are provided to give you examples of using HP 86120A remote programming commands in typical applications. They are not meant to teach general programming techniques or provide ready-to-use solutions.
Page 103
Tempo subroutine This subroutine, which is only found in example 3, pauses the program for a few seconds while the HP 86120A measures the drift on a laser. The argument in the example sets the pause for 10 seconds. 3-31...
This program measures the power and wavelength of a DFB laser. It first sets the HP 86120A in the single-acquisition measurement mode. Then, it triggers the HP 86120A with the MEASure command to capture measurement data of the input spectrum. Because the data is stored in the instrument’s memory, it can be queried as needed.
Page 105
Programming Example Programs COM /Instrument/ @Mwm ASSIGN @Mwm TO 720 Set_ese PRINT USING "37A,33A";"Multi-Wavelength Meter Identity is : ";FNIdentity$ OUTPUT @Mwm;":INIT:CONT OFF" ON TIMEOUT 7,5 CALL Err_mngmt OUTPUT @Mwm;":MEAS:SCAL:POW:WAV?" ENTER @Mwm;Current_wl OUTPUT @Mwm;":FETC:SCAL:POW?" ENTER @Mwm;Current_pwr OFF TIMEOUT PRINT USING "20A,4D.3D,3A,19A,M2D.2D,4A";"The wavelength is : ";Current_wl /1.0E-9;"...
Page 106
First, the program sets the HP 86120A in the single-acquisition measurement mode. Then, it triggers the HP 86120A with the MEASure command to capture measurement data of the input spectrum. Because the data is stored in the instrument’s memory, it can be queried as needed.
Page 107
Programming Example Programs Err_mngmt:SUB Err_mngmt COM /Instrument/ @Mwm DIM Err_msg$[255] INTEGER Cme CLEAR 7 REPEAT OUTPUT @Mwm; "*ESR?" ENTER @Mwm;Cme OUTPUT @Mwm; ":SYST:ERR?" ENTER @Mwm;Err_msg$ PRINT Err_msg$ UNTIL NOT BIT(Cme,2) AND NOT BIT(Cme,4) AND NOT BIT(Cme,5) AND Err$,"+0") Subend:SUBEND Set_ese:SUB Set_ese COM /Instrument/ @Mwm OUTPUT @Mwm;...
Page 108
This program measures the drift of a Fabry Perot laser. It measures drift in both power and wavelength of each line. First, the program sets the HP 86120A in the continuous-acquisition measurement mode. Then, it mea- sures drift using commands from the CALCulate3 subsystem.
Page 109
Programming Example Programs ! Query reference wavelengths and powers OUTPUT @Mwm;":CALC3:DATA? WAV" ENTER @Mwm USING "#,K";Current_ref_wl(*) OUTPUT @Mwm;":CALC3:DATA? POW" ENTER @Mwm USING "#,K";Current_ref_pwr(*) ! Turn off drift reference state Cmd_opc(":CALC3:DRIF:REF:STAT OFF") Err_mngmt(":CALC3:DRIF:REF:STAT OFF") ! Turn on drift max min calculation Cmd_opc(":CALC3:DRIF:DIFF:STAT ON") Err_mngmt(":CALC3:DRIF:DIFF:STAT ON") Tempo(10)
Page 110
Programming Example Programs Err_mngmt:SUB Err_mngmt(OPTIONAL Cmd_msg$) COM /Instrument/ @Mwmt DIM Err_msg$[255] INTEGER Cme CLEAR @Mwm REPEAT OUTPUT @Mwm;"*ESR?" ENTER @Mwm;Cme OUTPUT @Mwm;":SYST:ERR?" ENTER @Mwm;Err_msg$ IF NPAR>0 AND NOT POS(Err_msg$,"+0") THEN PRINT "This command ";Cmd_msg$;" makes the following error :" IF NOT POS(Err_msg$,"+0") THEN PRINT Err_msg$ UNTIL NOT BIT(Cme,2) AND NOT BIT(Cme,4) AND NOT BIT(Cme,5) AND POS(Err_msg$,"+0") Subend:SUBEND...
Page 111
Programming Example Programs Example 4. Measure laser-line separation This program measures the line separations on a Fabry Perot laser. It mea- sures separation (delta) between power and wavelength of each line using commands from the CALCulate3 subsystem. Refer to the introduction to this section for a description of each subroutine that is contained in this program.
Page 112
Programming Example Programs OFF TIMEOUT FOR I=1 TO Nb_pt-1 PRINT USING "6A,2D,17A,M4D.3D,31A,S2D.2D,4A";"Line :";I;" wavelength is : ";(Delta_wl(I)+((NOT I=1)*Delta_wl(1)))/ 1.0E-9;" nm. Absolute line level is : ";Delta_pwr(I)+(NOT I=1)*Delta_pwr(1);" dBm" PRINT USING "17A,2D,6A,M4D.3D,23A,2D,6A,S2D.2D,3A";"Delta Wl to line ",I+1," is : ";(Delta_wl(I+1)-(NOT I=1)*Delta_wl(I))/ 1.E-9;" nm, Delta Pwr to line ",I+1," is : ";(I=1)*(Delta_pwr(I+1))+(NOT I=1)*(Delta_pwr(I+1)- Delta_pwr(I));"...
Page 113
Programming Example Programs Cmd_opc:SUB Cmd_opc(Set_cmd$) COM /Instrument/ @Mwm OUTPUT @Mwm;Set_cmd$ OUTPUT @Mwm;"*OPC?" ENTER @Mwm;Opc_done$ SUBEND 3-41...
Page 114
Programming Example Programs Example 5. Measure signal-to-noise ratio This program measures signal-to-noise ratios on a Fabry Perot laser. It mea- sures the ratio for each line using commands from the CALCulate3 subsystem. Refer to the introduction to this section for a description of each subroutine that is contained in this program.
Page 115
Programming Example Programs FOR I=1 TO Nb_pt PRINT USING "7A,2D,17A,M4D.3D,25A,S2D.2D,22A,2D.2D,3A";"Line : ";I;" wavelength is : ";Current_wl(I)/1.0E-9;" nm, absolute level is : ";Current_pwr(I);" dBm, with a SNR of : ";Snr_pwr(I);" dB" NEXT I STOP Error_msg: ! PRINT "The program is aborted due to : ";ERRM$ Err_mngmt:SUB Err_mngmt(OPTIONAL Cmd_msg$) COM /Instrument/ @Mwmt DIM Err_msg$[255]...
Sources. Essentially, the HP 86120A’s accuracy is transferred to the tunable laser source. The absolute accuracy of the tunable laser source is increased from <±0.1 nm to <±0.005 nm which is the HP 86120A’s absolute accuracy (at 1550 nm). In order to run this program, the tunable laser source’s firmware must support the automatic alignment command, WAVEACT.
Page 117
Programming Example Programs COM Current_wl,Diff_wl.Target_wl,Previous_diff,Diff_diff Current_wl=0 Diff_wl=0 Target_wl=0 Previous_diff=O Diff_diff=0 ASSIGN @Tls TO 724 ASSIGN @Mwm TO 720 ! Initialize instrument Identity$[50] Identity$="" OUTPUT @Tls;"*CLS" OUTPUT @Tls;"*IDN?" ENTER @TLS;identity$ PRINT "TLS IS A ";identity$ OUTPUT @Mwm;"*RST" OUTPUT @Mwm;"*CLS" OUTPUT @Mwm;"*IDN?" ENTER @Mwm;Identity$ PRINT "MWM IS A ";identity$ ! Ask user for desired wavelength...
Programming Lists of Commands Lists of Commands 7DEOH 60:1 3URJUDPPLQJ#&RPPDQGV#+4#RI#8, Command Description Code Codes: S indicates a standard SCPI command. I indicates an instrument specific command. Common Commands *CLS Clears all event registers and the error queue. *ESE Sets the bits in the standard-event status enable register *ESR? Queries value standard-event status register.
Page 119
Places the instrument in the average-wavelength mode. Data queries return the power-weighted average frequency, wavelength, or wavenumber or total power. :CALCulate2:WLIMit[:STATe] Limits input wavelength range of the HP 86120A. CALCulate3 Subsystem :CALCulate3:DATA? Queries the data resulting from delta, drift, and signal-to-noise measurements.
Page 120
Programming Lists of Commands 7DEOH 60:1 3URJUDPPLQJ#&RPPDQGV#+6#RI#8, Command Description Code Codes: S indicates a standard SCPI command. I indicates an instrument specific command. :CALCulate3:DRIFt:MAXimum[:STATe] Sets the drift calculation to return the maximum power (frequency) values measured. :CALCulate3:DRIFt:MINimum[:STATe] Sets the drift calculation to return the minimum power (frequency) values measured.
Page 121
SYSTem Subsystem :SYSTem:ERRor? Queries an error from the error queue. :SYSTem:HELP:HEADers? Queries an ASCII listing of all HP 86120A remote commands. :SYSTem:PRESet Performs the equivalent of a front-panel PRESET key press. :SYSTem:VERSion Queries the version of SCPI with which this instrument is compliant.
Page 122
Programming Lists of Commands 7DEOH 60:1 3URJUDPPLQJ#&RPPDQGV#+8#RI#8, Command Description Code Codes: S indicates a standard SCPI command. I indicates an instrument specific command. TRIGger Subsystem :ABORt Stops the current measurement sequence. :INITiate:IMMediate Places the instrument into the initiated state and initiates a new measurement sequence.
Page 123
:MEASure:ARRay:POWer:WNUMber COH LEN :MEASure:LENGth:COHerence:CLENgth Cont :INITiate:CONTinuous ON UNIT:POWer DRIFT :CALCulate3:DRIFt[:STATe] ELEV :SENSe:CORRection:ELEVation EXIT none FAST See UPDATE HP-IB none LIM OFF :CALCulate2:WLIMit[:STATe] OFF LIM ON :CALCulate2:WLIMit[:STATe] ON List by Power :CONFigure:ARRay:POWer List by WL :MEASure:ARRay:POWer:WAVelength :CALCulate3:DRIFt:MINimum[:STATe] and MAX-MIN :CALCulate3:DRIFt:MAXimum[:STATe] UNIT:POWer...
Page 124
Programming Lists of Commands Table 3-8. Keys Versus Commands (2 of 3) Equivalent Command NEXT PK :DISPlay:MARKer:MAXimum:NEXT NEXT WL :DISPlay:MARKer:MAXimum:RIGHt :MEASure:ARRay:POWer:WAVelength NORMAL See UPDATE :CALCulate3:DELTa:POWer[:STATe] :CALCulate3:DELTa:POWer[:STATe] PEAK :DISPlay:MARKer:MAXimum See NEXT PK, NEXT WL, PEAK, PREV PK, and PREV WL Peak WL PK EXC :CALCulate2:PEXCursion PK THLD...
Page 125
Programming Lists of Commands Table 3-8. Keys Versus Commands (3 of 3) Equivalent Command :MEASure:ARRay:POWer:FREQuency UNITS :UNIT:POWer UPDATE Measurement Instructions and :CALCulate1:TRANsform:FREQuency:POINts USER :CALCulate3:SNR:AUTO OFF USER WL :CALCulate3:SNR:REFerence[:WAVelength] UNIT:POWer VACUUM :SENSe:CORRection:MEDium VACuum See CM, NM, and THZ WL LIM CALCulate2:WLIMit[:STATe] WL REF See AUTO, USER, and USER WL 3-53...
Page 128
Programming Commands Programming Commands Programming Commands This chapter is the reference for all HP 86120A programming commands. Commands are organized by subsystem. Table 4-1. Notation Conventions and Definitions Convention Description < > Angle brackets indicate values entered by the programmer.
Common commands can be received and processed by the instrument whether they are sent over the HP-IB as separate program mes- sages or within other program messages.
Page 131
Programming Commands Common Commands 6\QWD[# *ESE <integer> *ESE? <integer> is an mask from 0 to 255. 'HVFULSWLRQ The event status enable register contains a mask value for the bits to be enabled in the event status register. A bit set to one (1) in the event status enable register enables the corresponding bit in the event status register to set the event summary bit in the status byte register.
Page 132
Programming Commands Common Commands *ESR? The *ESR (event status register) query returns the value of the event status register. 6\QWD[# *ESR? 'HVFULSWLRQ When you read the standard event status register, the value returned is the total of the bit weights of all of the bits that are set to one at the time you read the byte.
Page 133
The maximum length of the identification string is 50 bytes. 4XHU\#5HVSRQVH# The following identification string is returned. The last entry in the string is the firmware version number; this value may vary between instruments. HEWLETT-PACKARD, 86120A, 0, 1.000 ([DPSOH# DIM Id$[50] OUTPUT 720;”*IDN?”...
Page 134
This command is useful when the computer is sending commands to other instruments. The computer can poll the event status register to check when the HP 86120A has completed the operation. Use the *OPC? query to ensure all operations have completed before continuing the program. By following a command with an *OPC? query and an ENTER statement, the program will pause until the response (ASCII “1”) is returned by the instrument.
Page 135
Programming Commands Common Commands Table 4-4. Conditions Set by *RST Reset Item Setting Display mode single wavelength Wavelength range limiting Measurement acquisition single Wavelength calibration vacuum Elevation correction value 0 meters Wavelength units Amplitude units Amplitude offset 0 dB Peak threshold 10 dB Peak excursion 15 dB...
Page 136
Programming Commands Common Commands *SRE The *SRE (service request enable) command sets the bits in the service request enable register. 6\QWD[# *SRE <integer> *SRE? <integer> is defined as an integer mask from 0 to 255. 'HVFULSWLRQ The service request enable register contains a mask value for the bits to be enabled in the status byte register.
Page 137
Programming Commands Common Commands ([DPSOH# OUTPUT 720;”*SRE 32” In this example, the command enables ESB (event summary) bit 5 in the sta- tus byte register to generate a service request. *STB? The *STB (status byte) query returns the current value of the instrument’s status byte.
Page 138
Programming Commands Common Commands ([DPSOH# OUTPUT 720;”*STB?” ENTER 720;Value PRINT Value *TRG The *TRG (trigger) command is identical to the group execute trigger (GET) message or RUN command. 6\QWD[ *TRG 'HVFULSWLRQ This command acquires data according to the current settings. This command cannot be issued as a query.
Page 139
Programming Commands Common Commands *WAI The *WAI command prevents the instrument from executing any further com- mands until the current command has finished executing. 6\QWD[ *WAI 'HVFULSWLRQ All pending operations are completed during the wait period. This command cannot be issued as a query. 4-13...
Programming Commands Measurement Instructions Measurement Instructions Use the measurement instructions documented in this section to perform measurements and return the desired results to the computer. Four basic measurement instructions are used: CONFigure, FETCh, READ, and MEA- Sure. Because the command trees for each of these four basic measurement instructions are identical, only the MEASure tree is documented.
Page 141
Programming Commands Measurement Instructions The commands in this subsystem have the following command hierarchy: {:MEASure | :READ[?] | :FETCh[?] | :CONFigure[?]} {:ARRay | [:SCALar] } :POWer[?] :FREQuency[?] :WAVelength[?] :WNUMber[?] [SCALar]:LENGth :COHerence :ALPHa? :BETA? [:CLENgth]? :DELay? 4-15...
Page 142
Programming Commands Measurement Instructions MEASure{:ARRay | [:SCALar]} :POWer? Returns amplitude values. 6\QWD[# :POWer? [<expected_value>[,<resolution>]] Used With <expected_value> <resolution> SCALar optional ignored ARRay ignored ignored 'HVFULSWLRQ# When used with a :SCALar command, a single value is returned. The display is placed in the single-wavelength mode, and the marker is placed on the signal having a power level that is closest to the <expected_value>...
Page 143
Programming Commands Measurement Instructions ([DPSOHV# :CONF:ARR:POW :FETC:ARR:POW? :READ:ARR:POW? :MEAS:ARR:POW? :CONF:SCAL:POW -10 dBm :FETC:SCAL:POW? MAX :READ:SCAL:POW? MIN :MEAS:SCAL:POW? DEF 4XHU\#5HVSRQVH The following line is an example of a returned string when :MEAS:SCAL:POW? MAX is sent: -5.88346500E+000 If six laser lines are located and :MEAS:ARR:POW? is sent, the following string could be returned.
Page 144
Programming Commands Measurement Instructions MEASure{:ARRay | [:SCALar]} :POWer:FREQuency Returns frequency values. 6\QWD[# :POWer:FREQuency? [<expected_value>[,<resolution>]] Used With <expected_value> <resolution> SCALar optional optional ARRay ignored optional D1 $OWKRXJK#LJQRUHG/#WKLV#DUJXPHQW#PXVW#EH#SUHVHQW#LI#WKH#UHVROXWLRQ#DUJXPHQW#LV#VSHFLILHG1 'HVFULSWLRQ# When used with a :SCALar command, a single value is returned. The display is placed in the single-wavelength mode, and the marker is placed on the signal having a frequency that is closest to the <expected_value>...
Page 145
Programming Commands Measurement Instructions ?UHVROXWLRQ!# MAXimum 0.01 resolution (fast update) &RQVWDQWV MINimum 0.001 resolution (normal) DEFault Current resolution ([DPSOHV# :CONF:ARR:POW:FREQ DEF MIN :FETC:ARR:POW:FREQ? DEF MAX :READ:ARR:POW:FREQ? :MEAS:ARR:POW:FREQ? :CONF:SCAL:POW:FREQ 230.8THZ, MAX :FETC:SCAL:POW:FREQ? 230.8THZ, MIN :READ:SCAL:POW:FREQ? 230.8THZ :MEAS:SCAL:POW:FREQ? 230.8THZ 4XHU\#5HVSRQVH The following line is an example of a returned string when :MEAS:SCAL:POW:FREQ? MAX is sent: +1.94055176E+014 If six laser lines are located and :MEAS:ARR:POW:FREQ? is sent, the following...
Page 146
Programming Commands Measurement Instructions MEASure{:ARRay | [:SCALar]} :POWer:WAVelength Returns wavelength values. 6\QWD[# :POWer:WAVelength? [<expected_value>[,<resolution>]] Used With <expected_value> <resolution> SCALar optional optional ARRay ignored optional D1 $OWKRXJK#LJQRUHG/#WKLV#DUJXPHQW#PXVW#EH#SUHVHQW#LI#WKH#UHVROXWLRQ#DUJXPHQW#LV#VSHFLILHG1 'HVFULSWLRQ# When used with a :SCALar command, a single value is returned. The display is placed in the single-wavelength mode, and the marker is placed on the signal having a wavelength that is closest to the <expected_value>...
Page 147
Programming Commands Measurement Instructions ?UHVROXWLRQ!# MAXimum 0.01 resolution (fast update) &RQVWDQWV MINimum 0.001 resolution (normal) DEFault Current resolution ([DPSOHV# :CONF:ARR:POW:WAV DEF MAX :FETC:ARR:POW:WAV? DEF MIN :READ:ARR:POW:WAV? :MEAS:ARR:POW:WAV? :CONF:SCAL:POW:WAV 1300NM, MAX :FETC:SCAL:POW:WAV? 1300NM, MIN :READ:SCAL:POW:WAV? 1300NM :MEAS:SCAL:POW:WAV? 1300NM 4XHU\#5HVSRQVH The following line is an example of a returned string when :MEAS:SCAL:POW:WAV? MAX is sent: +1.5529258E-006 If six laser lines are located and :MEAS:ARR:POW:WAV? is sent, the following...
Page 148
Programming Commands Measurement Instructions MEASure{:ARRay | [:SCALar]} :POWer:WNUMber Returns a wave number value. 6\QWD[# :POWer:WNUMber? [<expected_value>[,<resolution>]] Used With <expected_value> <resolution> SCALar optional optional ARRay ignored optional D1 $OWKRXJK#LJQRUHG/#WKLV#DUJXPHQW#PXVW#EH#SUHVHQW#LI#WKH#UHVROXWLRQ#DUJXPHQW#LV#VSHFLILHG1 'HVFULSWLRQ# When used with a :SCALar command, a single value is returned. The display is placed in the single-wavelength mode, and the marker is placed on the signal having a wave number that is closest to the <expected_value>...
Page 149
Programming Commands Measurement Instructions ?UHVROXWLRQ!# MAXimum 0.01 resolution (fast update) &RQVWDQWV MINimum 0.001 resolution (normal) DEFault Current resolution ([DPSOHV# :CONF:ARR:POW:WNUM DEF MAX :FETC:ARR:POW:WNUM? DEF MIN :READ:ARR:POW:WNUM? :MEAS:ARR:POW:WNUM? :CONF:SCAL:POW:WNUM 6451, MAX :FETC:SCAL:POW:WNUM? 6451, MIN :READ:SCAL:POW:WNUM? 6451 :MEAS:SCAL:POW:WNUM? 6451 4XHU\#5HVSRQVH If the :MEAS:SCAL:POW:WNUM? 6451 command is sent, and a 1550 nm laser line is present, the following response would be returned to the computer: +6.45286262E+005 –1...
Page 150
Programming Commands Measurement Instructions MEASure[:SCALar]:LENGth:COHerence:BETA? Queries the beta constant. 6\QWD[# :LENGth:COHerence:BETA? $WWULEXWH#6XPPDU\ Query Only 'HVFULSWLRQ# The beta constant is a unitless ratio. MEASure[:SCALar]:LENGth:COHerence[:CLENgth]? Queries the coherence length of the input signal in meters. 6\QWD[# :LENGth:COHerence:CLENgth? $WWULEXWH#6XPPDU\ Query Only MEASure[:SCALar]:LENGth:COHerence:DELay? Queries the round-trip path delay in the laser chip. 6\QWD[# :LENGth:COHerence:DELay? $WWULEXWH#6XPPDU\...
Use the CALCulate1 commands to query uncorrected frequency-spectrum data. In NORMAL measurement update mode, 34,123 values are returned. If the HP 86120A is set for FAST measurement update mode (low resolution), 4,268 values are returned. The commands in this subsystem have the following command hierarchy:...
Page 152
Programming Commands CALCulate1 Subsystem DATA? Queries uncorrected frequency-spectrum data of the input laser line. 6\QWD[# :CALCulate1:DATA? $WWULEXWH#6XPPDU\ Preset State: not affected SCPI Compliance: standard Query Only 'HVFULSWLRQ# The returned values are in squared Watts (linear) units. No amplitude or fre- quency correction is applied to the values.
Page 153
1551.07 nm (in vacuum). If your program is aborted or interrupted after sending this query, the HP 86120A continues to process the data but does not place it in the output buffer. Because of the amount of data processed, the instrument will not respond to any new commands in its input buffer for up to 20 seconds.
Page 154
Always use an *OPC? query or a *WAI command to ensure that this command has the time to complete before sending any more commands to the instrument. Refer to “Always force the HP 86120A to wait for non-sequential commands” on page 3-13 for more information.
Page 155
Programming Commands CALCulate1 Subsystem 4XHU\#5HVSRQVH For normal update: +34123 For fast update: +4268 4-29...
Programming Commands CALCulate2 Subsystem CALCulate2 Subsystem Use the CALCulate2 commands to query corrected values frequency-spec- trum data. The commands in this subsystem have the following command hierarchy: :CALCulate2 :DATA? :PEXCursion :POINts? :PTHReshold :PWAVerage [:STATe] :WLIMit [:STATe] 4-30...
Page 157
Programming Commands CALCulate2 Subsystem DATA? Queries the corrected peak data of the input laser line. 6\QWD[# :CALCulate2:DATA? {FREQuency | POWer | WAVelength | WNUMber} Constant Description FREQuency Queries the array of laser-line frequencies after the peak search is completed. If :CALC2:PWAV:STAT is on, the power-weighted average frequency is returned.
Page 158
When there is no input signal, the POWer query returns –200 dBm; the WAVe- length query returns 100 nm (1.0E–7). PEXCursion Sets the peak excursion limit used by the HP 86120A to determine valid laser line peaks. 6\QWD[# :CALCulate2:PEXCursion{?| {<integer> | MINimum | MAXimum | DEFault}} <integer>...
Page 159
Always use an *OPC? query or a *WAI command to ensure that this command has the time to complete before sending any more commands to the instrument. Refer to “Always force the HP 86120A to wait for non-sequential commands” on page 3-13 for more information..
Page 160
Always use an *OPC? query or a *WAI command to ensure that this command has the time to complete before sending any more commands to the instrument. Refer to “Always force the HP 86120A to wait for non-sequential commands” on page 3-13 for more information.
Page 161
SCPI Compliance: instrument specific 'HVFULSWLRQ# When this function is on, the HP 86120A has an input range of 1200 nm to 1650 nm. When this function is off, the instrument displays peaks over the full wavelength range. If you are measuring signals between 1200 nm and 1650 nm, set this function on to avoid identifying spurious second harmonic peaks.
Programming Commands CALCulate3 Subsystem CALCulate3 Subsystem Use the CALCulate3 commands to perform delta, drift, and signal-to-noise measurements. To select a measurement, use one of the following STATe com- mands: CALC3:DELT:POW:STAT (delta power) CALC3:DELT:WAV:STAT (delta wavelength) CALC3:DELT:WPOW:STAT (delta power and wavelength) CALC3:DRIF:STAT (drift) CALC3:SNR:STAT...
Page 163
Programming Commands CALCulate3 Subsystem The commands in this subsystem have the following command hierarchy: :CALCulate3 :DATA? :DELTa :POWer [:STATe] :PRESet :REFerence :FREQuency :POWer? [:WAVelength] :WNUMber :WAVelength [:STATe] :WPOWer [:STATe] :DRIFt :DIFFerence [:STATe] :MAXimum [:STATe] :MINimum [:STATe] :PRESet :REFerence :RESet [:STATe] [:STATe] :POINts? :SNR...
Page 164
Programming Commands CALCulate3 Subsystem DATA? Queries the data resulting from delta, drift, and signal-to-noise measurements. 6\QWD[# :CALCulate3:DATA? {POWer | FREQuency | WAVelength | WNUMber} Argument Description POWer Queries the array of laser-line powers after the calculation is completed. FREQuency Queries the array of laser-line frequencies after the calculation is completed.
Page 165
Programming Commands CALCulate3 Subsystem DELTa:POWer[:STATe] Turns the delta-power measurement mode on and off. 6\QWD[# :CALCulate3:DELTa:POWer[:STATe]{?| {ON | OFF | 1 | 0}} $WWULEXWH#6XPPDU\ Preset State: off *RST State: off SCPI Compliance: instrument specific 'HVFULSWLRQ# When this state is on, the power of the reference laser line is subtracted from the power values of all laser lines except the reference.
Page 166
Programming Commands CALCulate3 Subsystem DELTa:REFerence:FREQuency Selects the reference laser line for DELTa calculations. 6\QWD[# :CALCulate3:DELTa:REFerence:FREQuency{?| {<real> | MINimum | MAXimum}} <real> is a frequency value that is within the following limits: Constant Description MINimum 181.6924 THz MAXimum 428.6 THz $WWULEXWH#6XPPDU\ Preset State: 428.6 THz (700 nm) *RST State:428.6 THz (700 nm) SCPI Compliance: instrument specific...
Page 167
Programming Commands CALCulate3 Subsystem DELTa:REFerence[:WAVelength] Selects the reference laser line for DELTa calculations. 6\QWD[# :CALCulate3:DELTa:REFerence[:WAVelength]{?| {<real> | MINimum | MAXimum}} <real> is a wavelength value that is within the following limits: Constant Description MINimum 700.0 nm MAXimum 1650.0 nm $WWULEXWH#6XPPDU\ Preset State: 700 nm (428.6 THz) *RST State: 700 nm (428.6 THz) laser line SCPI Compliance: instrument specific...
Page 168
Programming Commands CALCulate3 Subsystem $WWULEXWH#6XPPDU\ –1 Preset State: 14,286 cm (700 nm) –1 *RST State: 14,286 cm (700 nm) SCPI Compliance: instrument specific 'HVFULSWLRQ# The reference will be the laser line at the wave number closest to the wave number entered. Subsequent measurements will use the wave number closest to the reference wave number used for the previous measurement.
Page 169
Programming Commands CALCulate3 Subsystem DELTa:WPOWer[:STATe] Turns the delta wavelength and power measurement mode on and off. 6\QWD[# :CALCulate3:DELTa:WPOWer[:STATe]{?| {ON | OFF | 1 | 0}} $WWULEXWH#6XPPDU\ Preset State: off *RST State: off SCPI Compliance: instrument specific 'HVFULSWLRQ# When on, the wavelength of the reference laser line is subtracted from the wavelength values of all laser lines except the reference.
Page 170
Programming Commands CALCulate3 Subsystem DRIFt:DIFFerence[:STATe] Sets the drift calculation to subtract the minimum values measured from the maximum values measured. 6\QWD[# :CALCulate3:DRIFt:DIFFerence[:STATe]{?| {ON | OFF | 1 | 0}} $WWULEXWH#6XPPDU\ Preset State: off *RST State: off SCPI Compliance: instrument specific 'HVFULSWLRQ# Use the CALC3:DRIF:PRES command to turn off all the drift states before turning on this state.
Page 171
Programming Commands CALCulate3 Subsystem 'HVFULSWLRQ# Use the CALC3:DRIF:PRES command to turn off all the drift states before turning on this state. The CALC3:DATA? query returns the maximum power and frequency. Note Only one STATe command can be turned on at any one time. Attempting to turn more than one state on at a time results in a “–221 Settings Conflict”...
Page 172
Programming Commands CALCulate3 Subsystem DRIFt:PRESet Turns off all the drift states for DIFFerence, MAXimum, MINimum, and REF- erence. 6\QWD[# :CALCulate3:DRIFt:PRESet $WWULEXWH#6XPPDU\ Preset State: unaffected by *RST State: unaffected by SCPI Compliance: instrument specific Command Only 'HVFULSWLRQ# This command allows the CALC3:DATA? query to return the difference between the current measurement and the reference.
Page 173
Programming Commands CALCulate3 Subsystem $WWULEXWH#6XPPDU\ Preset State: off *RST State: off SCPI Compliance: instrument specific 'HVFULSWLRQ# When this command is set to on, the CALC3:DATA? command returns the ref- erence laser lines. Use the CALC3:DRIF:PRES command to turn off all the drift states before turning on the drift reference state.
Page 174
Programming Commands CALCulate3 Subsystem Note Only one STATe command can be turned on at any one time. Attempting to turn more than one state on at a time results in a “–221 Settings Conflict” error. Refer to “CALCulate3 Subsystem” on page 4-36 for additional information on selectingmeasure- ments.
Page 175
Always use an *OPC? query or a *WAI command to ensure that this command has the time to complete before sending any more commands to the instrument. Refer to “Always force the HP 86120A to wait for non-sequential commands” on page 3-13 for more information.
Page 176
Programming Commands CALCulate3 Subsystem The default units for the <real> parameter is Hz. SNR:REFerence[:WAVelength] Sets the wavelength used for the noise measurement reference in the signal- to-noise calculation. 6\QWD[# :CALCulate3:SNR:REFerence[:WAVelength]{?| {<real> | MINimum | MAXyimum}} <real> is a wavelength value that is within the following limits: Constant Description MINimum...
Page 177
Programming Commands CALCulate3 Subsystem Constant Description MINimum 6060 (1650 nm) MAXimum 14286 (700 nm) $WWULEXWH#6XPPDU\ Preset State: unaffected by *RST State: 1550.0 nm in a vacuum. SCPI Compliance: instrument specific 'HVFULSWLRQ# After entering this value, use the SNR:AUTO command to configure the instrument to use this value in subsequent signal-to-noise calculations.
Programming Commands CONFigure Measurement Instruction CONFigure Measurement Instruction For information on the CONFigure measurement instruction, refer to “Mea- surement Instructions” on page 4-14. 4-52...
Programming Commands DISPlay Subsystem DISPlay Subsystem The commands in this subsystem have the following command hierarchy: :DISPlay :MARKer: :MAXimum :LEFT :NEXT :PREVious :RIGHt [:WINDow] :GRAPhics :STATe 4-53...
Page 180
Programming Commands DISPlay Subsystem MARKer:MAXimum Sets the marker to the laser line that has the maximum power. 6\QWD[# :DISPlay:MARKer:MAXimum $WWULEXWH#6XPPDU\ Preset State: marker set to maximum-power laser line *RST State: marker set to maximum-power laser line SCPI Compliance: instrument specific Command Only MARKer:MAXimum:LEFT Moves the marker left to the next laser line.
Page 181
Programming Commands DISPlay Subsystem MARKer:MAXimum:NEXT Moves the marker to the laser line with the next lower power level. 6\QWD[# :DISPlay:MARKer:MAXimum:NEXT $WWULEXWH#6XPPDU\ Preset State: marker set to maximum-power laser line *RST State: marker set to maximum-power laser line SCPI Compliance: instrument specifid Command Only 'HVFULSWLRQ# If the display is in the List by WL mode, it will be changed to List by Ampl before...
Page 182
Programming Commands DISPlay Subsystem MARKer:MAXimum:RIGHt Moves the marker right to the next laser line. 6\QWD[# :DISPlay:MARKer:MAXimum:RIGHt $WWULEXWH#6XPPDU\ Preset State: marker set to maximum-power laser line *RST State: marker set to maximum-power laser line SCPI Compliance: instrument specific Command Only 'HVFULSWLRQ# Moves the marker from the current marker position to the next laser line hav- ing the following characteristic: •...
Programming Commands FETCh Measurement Instruction FETCh Measurement Instruction For information on the FETCh measurement instruction, refer to “Measure- ment Instructions” on page 4-14. 4-57...
Prints measurement results on a printer. 6\QWD[# :HCOPy:IMMediate $WWULEXWH#6XPPDU\ Preset State: none *RST State: none SCPI Compliance: standard Command Only 'HVFULSWLRQ# Connect the printer to the HP 86120A’s rear-panel PARALLEL PRINTER PORT con- nector. The output to the printer is ASCII text. 4-58...
Programming Commands MEASure Measurement Instruction MEASure Measurement Instruction For information on the MEASure measurement instruction, refer to “Measure- ment Instructions” on page 4-14. 4-59...
Programming Commands READ Measurement Instruction READ Measurement Instruction For information on the READ measurement instruction, refer to “Measure- ment Instructions” on page 4-14. 4-60...
Programming Commands SENSe Subsystem SENSe Subsystem Use the SENSe commands to correct measurement results for elevation above sea level and to select between measurements in air or vacuum. You can also enter an amplitude offset. The commands in this subsystem have the following command hierarchy: [:SENSe] :CORRection...
Page 188
Always use an *OPC? query or a *WAI command to ensure that this command has the time to complete before sending any more commands to the instrument. Refer to “Always force the HP 86120A to wait for non-sequential commands” on page 3-13 for more information.
Page 189
Programming Commands SENSe Subsystem CORRection:MEDium Sets the HP 86120A to return wavelength readings in a vacuum or standard air. 6\QWD[# :SENSe:CORRection:MEDium{?| {AIR | VACuum}} Argument Description Selects wavelength values in standard air. VACuum Selects wavelength values in a vacuum. $WWULEXWH#6XPPDU\...
Page 190
Programming Commands SENSe Subsystem $WWULEXWH#6XPPDU\ Preset State: 0.0 *RST State: 0.0 SCPI Compliance: standard 4XHUU\#5HVSRQVH The query form returns the current offset setting as shown in the following example: +5.00000000E+000 DATA? Queries the time domain samples of the input laser line. 6\QWD[# :SENSe:DATA? $WWULEXWH#6XPPDU\...
Page 191
If your program is aborted or interrupted after sending this query, the HP 86120A continues to process the data but does not place it in the output buffer. Because of the amount of data processed, the instrument will not respond to any new commands in its input buffer for 30 or 40 seconds.
Programming Commands STATus Subsystem STATus Subsystem Use the commands in this subsystem to control the HP 86120A’s status- reporting structures. These structures provide registers that you can use to determine if certain events have occurred. The commands in this subsystem have the following command hierarchy:...
Programming Commands STATus Subsystem {OPERation | QUEStionable}:CONDition? Queries the value of the questionable or operation condition register. 6\QWD[# :STATus:{OPERation | QUEStionable}:CONDition? 4XHU\#5HVSRQVH# 0 to 32767 $WWULEXWH#6XPPDU\ Preset State: none *RST State: none SCPI Compliance: standard Query Only 'HVFULSWLRQ# Use this command to read the value of the OPERation Status or QUEStionable Status registers.
Programming Commands STATus Subsystem ([DPSOH# OUTPUT 720;”:STATUS:QUESTIONABLE:ENABLE 1024” 4XHU\#5HVSRQVH# When queried, the largest value that can be returned is 65535. This is because the most-significant register bit cannot be set true. {OPERation | QUEStionable}[:EVENt] Queries the contents of the questionable or operation event registers. 6\QWD[# :STATus:{OPERation | QUEStionable}:EVENt? 4XHU\#5HVSRQVH#...
Programming Commands STATus Subsystem $WWULEXWH#6XPPDU\ Preset State: none *RST State: none SCPI Compliance: standard 'HVFULSWLRQ Changes in the state of a condition register bit causes the associated OPERa- tion Status or QUEStionable Status register bit to be set. This command allows you to select a negative bit transition to trigger an event to be recognized.
Page 196
Programming Commands STATus Subsystem PRESet Presets the enable registers and the PTRansition and NTRansition filters. 6\QWD[# :STATus:PRESet $WWULEXWH#6XPPDU\ Preset State: none *RST State: none SCPI Compliance: standard Command Only 'HVFULSWLRQ# The PRESet command is defined by SCPI to affect the enable register. If you want to clear all event registers and queues, use the *CLS command.
Programming Commands SYSTem Subsystem SYSTem Subsystem The commands in this subsystem have the following command hierarchy: :SYSTem :ERRor? :HELP :HEADers? :PRESet :VERSion? 4-71...
Page 198
Query Only 'HVFULSWLRQ# The HP 86120A has a 30 entry error queue. The queue is a first-in, first-out buffer. Repeatedly sending the query :SYSTEM:ERROR? returns the error numbers and descriptions in the order in which they occur until the queue is empty.
Page 199
Programming Commands SYSTem Subsystem HELP:HEADers? Queries a listing of all the remote programming commands available for the HP 86120A. 6\QWD[# :SYSTem:HELP:HEADers? $WWULEXWH#6XPPDU\ Preset State: none *RST State: none SCPI Compliance: instrument specific Query Only 'HVFULSWLRQ# The returned ASCII string of commands is in the IEEE 488.2 arbitrary-block data format.
Page 200
Programming Commands SYSTem Subsystem PRESet Performs the equivalent of pressing the front-panel PRESET key. 6\QWD[# :SYSTem:PRESet $WWULEXWH#6XPPDU\ Preset State: none *RST State: none SCPI Compliance: standard Command Only 'HVFULSWLRQ# The instrument state is set according to the settings shown in the following table.
Page 201
∆ wavelength reference signal position 700 nm 700 nm Signal-to-Noise Measurements measurement user frequency 193.4144 THz last state user wavelength 1550 nm in vacuum last state HP-IB address not affected last state Power-bar display last state D1 7KH#WHUP#´ODVW#VWDWHµ#UHIHUV#WR#WKH#ODVW#VHWWLQJ#WKDW#WKLV#SDUDPHWHU#ZDV#LQ#EHIRUH#WKH#LQVWUXPHQW SRZHU#ZDV#WXUQHG#RII1 4-75...
Page 202
Programming Commands SYSTem Subsystem VERSion Queries the version of SCPI that the HP 86120A complies with. 6\QWD[# :SYSTem:VERSion $WWULEXWH#6XPPDU\ Preset State: none *RST State: none SCPI Compliance: standard Query Only 'HVFULSWLRQ# The SCPI version used in the HP 86120A is 1995.0.
Programming Commands TRIGger Subsystem TRIGger Subsystem The SCPI definition defines the TRIGger subsystem to include ABORt, ARM, INITiate, and TRIGger commands. The HP 86120A has no ARM or TRIGger commands. The commands in this subsystem have the following command hierarchy: ABORt...
Programming Commands TRIGger Subsystem ABORt Halts the current measurement sequence and places the instrument in the idle state. 6\QWD[# :ABORt $WWULEXWH#6XPPDU\ Preset State: not affected SCPI Compliance: standard Command Only 'HVFULSWLRQ# If the instrument is configured for continuous measurements, a new measure- ment sequence will begin.
Page 205
Always use an *OPC? query or a *WAI command to ensure that this command has the time to complete before sending any more commands to the instrument. Refer to “Always force the HP 86120A to wait for non-sequential commands” on page 3-13 for more information.
Programming Commands UNIT Subsystem UNIT Subsystem The only command provided in this subsystem is the POWer command as shown in the following command hierarchy: :UNIT [:POWer] [:POWer] Sets the power units to watts (linear) or dBm (logarithmic). 6\QWD[# :UNIT[:POWer]{?| {W | DBM}} $WWULEXWH#6XPPDU\ Preset State: dBm *RST State: dBm...
Page 208
There are no adjustments required for the HP 86120A. Safety first! Before servicing the HP 86120A, familiarize yourself with the safety markings on the instrument and the safety instructions in this manual. This instrument has been manufactured and tested according to international safety stan- dards.
Page 209
Servicing Servicing W A R N I N G For continued protection against fire hazard, replace line fuse only with same type and ratings, (type T 6.3A/250V for 100/240V operation). The use of other fuses or materials is prohibited. &RQWHQWV# General Information 5-4 Electrostatic Discharge Information 5-12 Reducing ESD Damage 5-13...
Servicing General Information General Information Whenever you contact Hewlett-Packard about your HP 86120A, have the com- plete serial number and option designation available. This will ensure you obtain accurate service information. • Refer to Table 5-1 on page 5-6 for a list of service tools.
Page 211
Do not disturb any of the screws on the A1A1, A1A2, or A1A3 assemblies. Loosening or tightening these screws destroys the amplitude and wavelength calibration so that the HP 86120A no longer meets its published specifications. If the position of these screws is changed, return the instrument to Hewlett...
Page 212
Servicing General Information Table 5-1. Required Tools Tool HP Part Number Small Pozidriv screwdriver 8710-0899 Wire cutter 8710-0012 Long-nose pliers 8710-1107 5.5 mm nut driver 8710-1220 7 mm nut driver 8710-1217 TORX T-10 driver 8710-1623 TORX T-10 key, right angle (Options AXE & IX4)
Page 213
A1A1 Interferometer Assembly is disturbed. Second, if the cover is disturbed, the label will be damaged to indicate the tampering. Never remove this cover. This label provides the HP part number and serial number for the A1A1 Interferometer Assembly.
Page 214
Servicing General Information 7DEOH 8061 0DMRU#$VVHPEOLHV Reference Description Designator Optical Block Assembly A1A1 Interferometer. Part of A1. A1A2 Detector. Part of A1. A1A3 Laser. Part of A1. Power Supply Board Assembly High Voltage Power Supply Assembly Digital Signal Processing Board Assembly Main Board Assembly Front-Panel Assembly, includes A6A2.
Page 216
Servicing General Information 7DEOH 8071 &DEOH#$VVHPEOLHV Reference Description Designator Input Fiber Optic Cable Front-Panel Ribbon Cable Display Power Cable SMB Cable, 260 mm long SMB Cable, 310 mm long Detector Bias Cable Main Bus Cable Part of B1. Digital Signal Processing Ribbon Cable Control Cable for A1 Assembly.
Servicing Electrostatic Discharge Information 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. The following figure shows an example of a static-safe work station using two types of ESD protection: •...
• Personnel should be grounded with a resistor-isolated wrist strap before re- moving any assembly from the unit. • Be sure all instruments are properly earth-grounded to prevent a buildup of static charge. Table 5-5. Static-Safe Accessories HP Part Description Number × ×...
Servicing Troubleshooting Troubleshooting W A R N I N G The opening of covers or removal of parts is likely to expose dangerous voltages. Disconnect the instrument from all voltage sources while it is being opened. W A R N I N G The power cord is connected to internal capacitors that may remain live for five seconds after disconnecting the plug from its power supply.
Servicing Troubleshooting If a general problem occurs 1. Test the power supply voltages as described in “To check the power supply voltages” on page 5-17. 2. Test the A1 Optical Block Assembly as described in “To check the A1 Optical Block Assembly” on page 5-18. 3.
Page 223
Servicing Troubleshooting If the fan doesn’t run • Measure the +12V supply at A5J8 pin 4. Power for the fan, B1, is supplied through two resistors on the A5 assembly which drop the +15V supply to +12V. To check the power supply voltages 1.
Page 224
Servicing Troubleshooting To check the A1 Optical Block Assembly This procedure tests the output from the two photodetectors in the A1 assem- bly. 1. Measure the voltage at A5J7 pin 1. It should measure +13V. This voltage is for the A1 assembly’s reference laser. It is generated from +15V by a voltage-dropping resistor.
3. Use a small flat-blade screwdriver to open the pull-out fuse drawer. The recommended fuse is an IEC 127 5×20 mm, 6.3A, 250 V, HP part num- ber 2110-0703. Notice that an extra fuse is provided in a drawer located on the fuse holder.
Test 3. Polarization Dependence Test 4. Optical Input Return Loss Test 5. Amplitude Accuracy and Linearity Allow the HP 86120A to warm up for 15 minutes before doing any of the per- formance tests. Calibration Cycle This instrument requires periodic verification of performance. The instrument should have a complete verification of specifications at least once every year.
• Gas lamps • HeNe gas lasers C A U T I O N Do not exceed +18 dBm source power. The HP 86120A’s input circuitry can be damaged when total input power exceeds 18 dBm. 3URFHGXUH Use three or four light standards that cover the HP 86120A’s wavelength range.
• 1310 nm and 1550 nm lasers (>0 dBm output power) C A U T I O N Do not exceed +18 dBm source power. The HP 86120A’s input circuitry can be damaged when total input power exceeds 18 dBm.
6. Set the polarization controller to autoscan. 7. On the HP 86120A, press Peak WL, Appl’s, and then DRIFT. Press MAX-MIN so that both MAX and MIN in the softkey label are highlighted. The display shows the total drift since the drift measurement was started.
Do this by wrapping the cable 6 times around a 5 mm diameter mandrel. 10. The return-loss module measures the termination parameter. 11. Connect the HMS-10/HP/HRL to FC/PC patchcord to the HP 86120A’s front panel OPTICAL INPUT connector. 12. The lightwave multimeter measures the return loss. Compare this measurement with the specification listed in Chapter 6, “Specifications and...
Page 231
Do this by wrapping the cable 6 times around a 5 mm diameter mandrel. 11. The return-loss module measures the termination parameter. 12. Connect the HMS-10/HP/HRL to FC/APC patchcord to the HP 86120A’s front panel OPTICAL INPUT connector. 13. The lightwave multimeter measures the return loss. Compare this measurement with the specification listed in Chapter 6, “Specifications and...
(TXLSPHQW Amplitude linearityis performed using the following devices: • 1550 nm DFB lasers • Optical attenuator • HP 11896A Polarization Controller • Optical power meter 3URFHGXUH Polarization sensitivity To ensure measurement accuracy, minimize the movement of any fiber-optic cables dur- ing this procedure.
Page 233
19. Change the attenuator to the settings shown in Table 5-6. For each setting, record the power measured on the HP 86120A. After completing this step, the table’s column titled “HP 86120A Power Reading” should be completely filled in. 20. Calculate the “Linearity” value for each row in the table using the following...
Page 234
Servicing Testing Performance 21. Compare the linearity values with the specification listed in Chapter 6, “Specifications and Regulatory Information”. The data may show multiple amplitude plateaus separated by small amplitude steps. This is not a problem as long as the amplitude steps are within the linearity specification. 5-28...
Page 235
Servicing Testing Performance Table 5-6. Linearity Data Values Desired Power Attenuator Power Meter HP 86120A Linearity (dBm) Setting Reading Power Reading –1 –2 –3 –4 –5 –6 –7 –8 –9 –10 –11 –12 –13 –14 –15 –16 –17 –18 –19 –20...
Servicing Replacing Instrument Assemblies Replacing Instrument Assemblies This section provides step-by-step procedures to remove and replace the major instrument assemblies. These include the following procedures: To remove the instrument cover 5-31 To replace the A1 Optical Block Assembly 5-32 To replace the A3 High Voltage Power Supply Assembly 5-37 To replace a cable clip 5-41 To replace line filter assembly FL1 5-42 5-30...
Be sure to use extra caution to avoid damaging the EMI springs. If you damage an EMI spring, you can order a new one using HP part number 8160-0656. The part that is ordered with this number can be cut to provide 8 replacement springs.
Page 238
Do not disturb any of the screws on the A1A1, A1A2, or A1A3 assemblies. Loosening or tightening these screws destroys the amplitude and wavelength calibration so that the HP 86120A no longer meets its published specifications. If the position of these screws is changed, return the instrument to Hewlett Packard for service.
Page 239
Servicing Replacing Instrument Assemblies 1. Remove the instrument cover as described in “To remove the instrument cover” on page 5-31. 2. Disconnect fiber-optic cable W1 from the A1 assembly. Use caution to avoid touching the cable’s ferrule tip against the connector body. 3.
Page 240
Servicing Replacing Instrument Assemblies W A R N I N G To prevent shock, carefully unplug the laser’s high-voltage connector as described in the next step. This cable remains energized long after the instrument has been disconnected from the power source. Immediately after unplugging the connector, ground the two contacts of the male connector simultaneously on the side of the instrument to discharge the plasma tube.
Page 241
Servicing Replacing Instrument Assemblies 7. Place the instrument on its left side so that the A1 assembly will not accidentally fall out of the instrument when the securing screws are removed. 8. Disconnect cables W4 and W10, shown in the following figure, from their connectors on the A5 Main Board Assembly.
Page 242
Servicing Replacing Instrument Assemblies 9. While holding the A1 assembly with one hand, use a T-15 TORX driver to remove the four screws that attach the A1 assembly to the instrument. When reinstalling the A1 assembly, torque these four screws to 20 in/lbs. 10.
Page 243
Servicing Replacing Instrument Assemblies To replace the A3 High Voltage Power Supply Assembly W A R N I N G To prevent shock, do not cut or damage the high voltage cables when removing the cable ties in the following step. 1.
Page 244
Servicing Replacing Instrument Assemblies 5. Place the instrument on its left side. 6. Cut and remove the cable ties that secure the high voltage connector cable to the fan assembly. 7. Cut and remove the cable ties that secure cable W13. 8.
Page 245
Servicing Replacing Instrument Assemblies 9. Use a T-10 TORX driver to remove the four screws that attach the A3 assembly to the instrument’s side panel. 5-39...
Page 246
Servicing Replacing Instrument Assemblies 10. To install the A3 assembly, perform the steps in this procedure in reverse order. 5-40...
Servicing Replacing Instrument Assemblies To replace a cable clip Cable clips are used throughout the instrument to attach cables to sheet-metal housings. They attach with self-adhesive bonds. 1. Remove the old clip. 2. Remove any remaining glue. 3. Clean the surface using isopropyl alcohol. 4.
Servicing Replacing Instrument Assemblies To replace line filter assembly FL1 Although replacing FL1 is straightforward, be sure to observe the following points: • Tighten the screws (item 12 shown in Table 5-10 on page 5-52) that attach FL1 to 6 in-lbs. Do not use the recommended torque for M3 screws. Over tightening these screws will damage line filter’s flange.
To order a part that is not listed, include the following information with the order: • HP 86120A model number • HP 86120A serial number • Description of where the part is located, what it looks like, and its function (if known) •...
Page 250
• Direct ordering and shipment from Hewlett-Packard • No maximum or minimum on any mail order. (There is a minimum order amount for parts ordered through a local HP office when the orders require billing and invoicing.) • Prepaid transportation. (There is a small handling charge for each order.) •...
Page 252
Servicing Replaceable Parts 7DEOH 80:1 0DMRU#$VVHPEOLHV Reference HP Part Description Designator Number 86120-60010 Optical Block Assembly. Includes A1A1, A1A2, and A1A3. 86120-69010 Optical Block Assembly (exchange) A1A1 — Interferometer. Part of A1. Can not be ordered separately. A1A2 — Detector. Part of A1. Can not be ordered separately.
Page 256
Servicing Replaceable Parts 7DEOH 80<1 #)URQW03DQHO#3DUWV HP Part Item Description Number 08703-20098 Universal fiber-optic connector 0535-0031 Nut-hex with lock washer, M3 x 0.5, 2.4 mm thick 0515-0664 Screw, TORX T10 Pan Head, M3 x 0.5, 12 mm long 0515-0374 Screw, TORX T10 Pan Head, M3 x 0.5, 10 mm long...
Page 258
Replaceable Parts 7DEOH 80431 5HDU03DQHO#3DUWV HP Part Item Description Number — HP-IB connector. Part of W7 — Parallel port connector. Part of W7 2190-0034 Washer, lock, HLCL No. 8 0.168 in ID 0380-0644 Standoff, hex, 0.255 in long, 6-32 thread 2190-0584 Washer, lock, HLCL 3.0mm, 3.1 mm ID, 6.2 mm OD...
Page 260
Servicing Replaceable Parts 7DEOH 80441 #7RS#9LHZ#3DUWV HP Part Item Description Number 1400-0968 Cable clip, 0.75 in x 0.75 in 1400-0755 Component clip 0.75 in x 0.75 in 1400-1328 Cable mount, 1 in x 1 in 1400-2136 Cable mount, 0.75 in x 0.75 in 0515-0372 Screw, TORX T10 Pan Head, M3 x 0.5, 8 mm long...
Page 262
Servicing Replaceable Parts 7DEOH 80451 %RWWRP#9LHZ#3DUWV HP Part Item Description Number 1400-1439 Cable clip 0515-0372 Screw, TORX T10 Pan Head, M3 x 0.5, 8 mm long 0515-0430 Screw, TORX T10 Pan Head, M3 x 0.5, 6 mm long 86120-20018 Heatsink...
Page 264
Servicing Replaceable Parts 7DEOH 80461 #6LGH#9LHZ#3DUWV HP Part Item Description Number 0515-1102 Screw, TORX T10 Flat Head, M3 x 0.5, 8 mm long 0515-2086 Screw, TORX T15 Flat Head, M4 x 0.7, 7 mm long 0515-0430 Screw with washer, TORX T10 Pan Head, M3 x 0.5, 6 mm long...
Page 266
Servicing Replaceable Parts 7DEOH 80471 #,QVWUXPHQW#&RYHU#3DUWV HP Part Item Description Number 0515-0380 Screw, TORX T15 Pan Head, M4 x 0.7,10 mm long 0515-1227 Screw, TORX T10 Flat Head, M3 x 0.5, 6 mm long 01650-47701 Molded feet 1460-1345 Spring leg...
Page 270
Specifications and Regulatory Information Specifications and Regulatory Information Specifications and Regulatory Information This chapter lists specification and characteristics of the instrument. The dis- tinction between these terms is described as follows: • Specifications describe warranted performance over the temperature range 0°C to +55°C and relative humidity <95% (unless otherwise noted).
Specifications and Regulatory Information Definition of Terms Definition of Terms Wavelength Range refers to the allowable wavelength range of the optical input signal. Absolute accuracy indicates the maximum wavelength error over the allowed environmental conditions. The wavelength accuracy is based on fundamental physical constants, which are absolute standards not requiring traceability to artifacts kept at national standards laboratories.
Page 272
Specifications and Regulatory Information Definition of Terms Amplitude Calibration Accuracy indicates the maximum power calibration error at the specified wavelengths over the allowed environmental conditions. The ampli- tude calibration acccuracy is tracable to a National Institute of Standards and Technology (NIST) calibrated optical power meter. NIST is the national stan- dards laboratory of the United States.
Page 273
Specifications and Regulatory Information Definition of Terms Measurement Cycle Measurement cycle time refers to the cycle time when measuring wavelength Time and power of laser lines. Specific advanced applications may require longer cycle times.
Specifications and Regulatory Information Specifications Specifications Each laser line is assumed to have a widewith (including modulation side- bands) of less than 10 GHz. All specifications apply when the instrument is in NORMAL UPDATE mode unless noted. Wavelength Range 700-1650 nm (182-428 THz) ≥...
Page 275
Specifications and Regulatory Information Specifications Amplitude ± Calibration accuracy at calibration wavelengths 30 nm ± 1310 and 1550 nm 0.5 dB ± 780 nm (characteristic) 0.5 dB ± Flatness, 30 nm from any wavelength ± 1200-1600 nm (characteristic) 0.2 dB ±...
Specifications and Regulatory Information Specifications Selectivity ≥ 25 dB Two lines input separated by 100 GHz (characteristic) ≥ 10 dB Two lines input separated by 30 GHz (characteristic) Input Power +10 dBm Maximum displayed level (sum of all lines) +18 dBm Maximum safe input level (sum of all lines) Maximum Number of Laser Lines Input Input Return Loss...
Specifications and Regulatory Information Specifications Operating Specifications indoor Power: 115 VAC: 110 VA MAX. / 60 WATTS MAX. / 1.1 A MAX. 230 VAC: 150 VA MAX. / 70 WATTS MAX. / 0.6 A MAX. Voltage nominal: 115 VAC / 230 VAC range 115 VAC: 90-132 V range 230 VAC: 198-254 V Frequency...
Specifications and Regulatory Information Regulatory Information Regulatory Information • Laser Classification: This product contains an FDA Laser Class I (IEC Laser Class 1) laser. • This product complies with 21 CFR 1040.10 and 1040.11. Notice for Germany: Noise Declaration Acoustic Noise Emission Geraeuschemission LpA <...
Page 279
Specifications and Regulatory Information Regulatory Information I’ll 6-11...
Page 280
Specifications and Regulatory Information Regulatory Information Front view of instrument Rear new of instrument 6-12...
Reference Instrument Preset Conditions Instrument Preset Conditions Table 7-1. Instrument Conditions (1 of 2) Settings after Settings after Item Preset Key Pressed Power Turned On Display mode single wavelength last state Wavelength range limiting last state Measurement acquisition continuous last state Wavelength calibration vacuum last state...
Page 284
Reference Instrument Preset Conditions Table 7-1. Instrument Conditions (2 of 2) Settings after Settings after Item Preset Key Pressed Power Turned On HP-IB address not affected last state Power-bar display last state D1 7KH#WHUP#´ODVW#VWDWHµ#UHIHUV#WR#WKH#ODVW#VHWWLQJ#WKDW#WKLV#SDUDPHWHU#ZDV#LQ#EHIRUH#WKH#LQVWUXPHQW SRZHU#ZDV#WXUQHG#RII1...
Menu Maps Menu Maps This section provides menu maps for the HP 86120A softkeys. The maps show which softkeys are displayed after pressing a front-panel key; they show the relationship between softkeys. The softkeys in these maps are aligned verti- cally instead of horizontally as on the actual display.
Reference Menu Maps Display Avg WL Menu There is no menu associated with this key. Measurement Cont Menu There is no menu associated with this key. Display List by Power Menu...
Reference Error Messages Error Messages In this section, you’ll find all the error messages that the HP 86120A can dis- play on its screen. Table 7-2 on page 7-12 lists all instrument-specific errors. Table 7-3 on page 7-15 lists general SCPI errors.
Page 293
Reference Error Messages Table 7-2. Instrument Specific Error Messages (2 of 3) Error Number Error Message ROM BYTE UNERASED ROM WRITE OPERATION FAILED ROM DEFECTIVE ROM DATA INVALID ROM VERSION INCOMPATIBLE ROM POLLING LIMITED OUT INPUT OUT OF RANGE BAD CAL ROM DATA BAD CAL ROM DATA BAD CAL ROM DATA BAD CAL ROM DATA...
Page 294
Reference Error Messages Table 7-2. Instrument Specific Error Messages (3 of 3) Error Number Error Message PRINTER TIMED OUT PRINTOUT WAS ABORTED NOT ALLOWED IN COH LEN NOT ALLOWED IN S/N UNKNOWN KEYPRESS NUM LINES < NUM REFS NUM LINES > NUM REFS NO REFERENCE SIGNAL UNKNOWN ERROR 7-14...
Page 295
Reference Error Messages Table 7-3. General SCPI Error Messages (1 of 3) Error Number Desription “No errors” –100 “Command error (unknown command)“ –101 “Invalid character“ –102 “Syntax error“ –103 “Invalid separator“ –104 “Data type error“ –105 “GET not allowed“ –108 “Parameter not allowed“...
Page 296
Reference Error Messages Table 7-3. General SCPI Error Messages (2 of 3) Error Number Desription –158 “String data not allowed“ –161 “Invalid block data“ –168 “Block data not allowed“ –170 “Expression error“ –171 “Invalid expression“ –178 “Expression data not allowed“ –200 “Execution error“...
Page 297
Reference Error Messages Table 7-3. General SCPI Error Messages (3 of 3) Error Number Desription –310 “System error“ –321 “Out of memory” –350 “Too many errors“ –400 “Query error“ –410 “Query INTERRUPTED“ –420 “Query UNTERMINATED“ –430 “Query DEADLOCKED“ –440 “Query UNTERMINATED after indef resp“ Query was unterminated after an indefinite response.
Reference Front-Panel Fiber-Optic Adapters Front-Panel Fiber-Optic Adapters The FC/PC adapter is the standard adapter supplied with the instrument. 7-18...
Reference Hewlett-Packard Sales and Service Offices Hewlett-Packard Sales and Service Offices Hewlett-Packard Sales and Service Offices (1 of 2) U.S. FIELD OPERATIONS Headquarters California, Northern California, Southern Hewlett-Packard Company Hewlett-Packard Company Hewlett-Packard Company 19320 Pruneridge Avenue 301 East Evelyn 1421 South Manhatten Ave. Cupertino, CA 95014 U.S.A.
Page 301
Reference Hewlett-Packard Sales and Service Offices Hewlett-Packard Sales and Service Offices (2 of 2) INTERCON FIELD OPERATIONS Headquarters Australia Canada Hewlett-Packard Company Hewlett-Packard Australia Ltd. Hewlett-Packard Ltd. 3495 Deer Creek Rd. 31-41 Joseph Street 17500 South Service Road Palo Alto, California 94304-1316 Blackburn, Victoria 3130 Trans-Canada Highway (415) 857-5027...
Page 302
Reference Hewlett-Packard Sales and Service Offices 7-22...
Page 303
ABORT softkey, 2-37 bit error rate, 2-25 ac power cables, 1-8 block diagram, 3-6 adding parameters, 3-26 BY PWR annotation, 2-5 address. See HP-IB address BY WL annotation, 2-5 adjustments, 5-2 air, measurements in, 2-34 alpha factor, 2-29, 2-30 cabinet, cleaning, 1-2...
Page 304
5-13 DBM softkey, 2-11 *ESE, 3-30, 4-4 declaration of conformity, 6-11 *ESR, 4-6 default HP-IB address, 3-4 EVENT programming command, 4-67, 4-68 DELay? programming command, 4-24 event status enable register, 3-30, 4-5 Delta Off softkey. See Off example programs, 3-30 Delta On softkey.
Need help?
Do you have a question about the 86120A and is the answer not in the manual?
Questions and answers