Save and Recall a File

You can save and recall files to and from an internal or external storage device in a variety of file formats.

How to Save Instrument State
How to Save Measurement Data
How to Recall a File
About Instrument State and Calibration Data ( .csa, .cst, .sta, .cal)
About Measurement Data Files (.prn, .snp, .cti, .csv, .mdf)
Managing Files without a Mouse

Data Scope

Determines what traces are saved to a file. Available ONLY with *.cti, *.csv, and *.mdf.

Auto
- When correction is OFF, saves the specified trace.
- When correction is ON, saves all corrected parameters associated with the calibrated ports in the Cal Set.
- For GCA and Swept IMD channels, saves the active trace only.
Single Trace - Saves the active trace.
Displayed Traces - Saves all displayed traces for all channels.

Format

Determines the format of the data. Available with (CTI Formatted, CSV, SNP, MDIF)

Auto - Data is saved in LogMag or LinMag if one of these is the currently selected display format. If format is other than these, then data is saved in Real/Imag.
Displayed Format (CSV and MDIF only) - Data is saved in the format of the displayed trace.
LogMag, LinMag, Real/Imag - Select output format.
- The imaginary portion for all LogMag and LinMag data is saved in degrees.
- Real/ Imag data is never smoothed.

Note: .prn files can only save the active trace in the displayed format.

Save Saves the file to the specified file name and directory.

How to Recall (open) a file Use one of the following methods:
Using front-panel hardkey [softkey] buttons	Using Menus
Press Recall then [Recall] Select from a list of 12 files shown on softkeys. The list can be sorted by 'most recently used' or alphabetically depending on a preference. The preference setting appears at the bottom of the second page of softkeys listing files to be recalled, or on the Preference dialog. or press Recall to start the following dialog.	Click File then Recall Select from the top 6 'most recently used' list. or click Recall to start the following dialog.

Recall dialog box help

Look in Allows you to select the directory that contains the file that you want to recall.

Filename Displays the filename that you either typed in or clicked on in the directory contents box.

Files of type Allows you view and select files that are listed in categories of a file type. The following types of files can be recalled into the analyzer: All State files, Citi files, SNP files.

Recalling instrument state files

When an Instrument State file is recalled, the current state of the instrument is overwritten with the recalled state. A *.cal file does not contain an instrument state, but only calibration data. Learn more about Instrument States.

Recalling Data files

Citi files and SNP files can be recalled and viewed in the analyzer.

Click File then Recall.
Select Citifile Data or Snp.
Select the file to recall
Click Recall.

Note: Filenames (not including the path name) that are longer than 64 characters will NOT be recalled.

Recalled data is ALWAYS displayed using LogMag format, regardless of how the file was stored.

The channel is placed in Trigger Hold. If triggering is resumed, the data will be overwritten.

SNP files are recalled as traces into a single window and channel, beginning at the highest available channel number allowed on the analyzer. For multi-port SNP files (greater than 4 ports), if the number of S parameters in the file is beyond the maximum number of traces in a window, then new windows will be created.

Citi files are recalled into the same window and channel configuration as when they were saved. However, the new recalled channel numbers begin with the highest channel number allowed on the analyzer and decrement for each additional channel.

For example, when a citi file is saved, two traces are in window 1, channel 1 and two additional traces are in window 2, channel 2. When recalled into a factory preset condition (1 trace in window 1, channel 1), the first two recalled traces appear in window 2, highest channel number, and the second two traces appear in window 3, (highest channel number -1). See also Traces, Channels, and Windows.

Recall Recalls the file displayed in the file name box.

Instrument State / Calibration Files

You can save, and later recall, instrument settings and calibration data for all channels currently in use on the analyzer.

An Instrument State contains almost every analyzer setting. The following settings are NOT saved and recalled with Instrument State:

GPIB address
RF power ON/OFF (depends on current setting)
Test set I/O settings

The following file types are used to save and recall instrument states and Cal Set information:

File Types

Information that is stored for each channel

.csa	.cst		.sta	Instrument State Information
				Channels/Traces	Averaging
				Windows	Markers
				Triggering	Math/memory
				Format	Limits
				Scale	More...
				Stimulus Information:
				Frequency range	Alternate sweep
				Number of points	Port powers
				IF bandwidth	Source attenuators
				Sweep type	Receiver attenuators
				Sweep mode	Test Set port map
		.cal		Cal Set Information
				GUID (Globally Unique Identifier) provides link to Cal Set
				Name, Description, Modify date
				Stimulus Information:
				Frequency range	Alternate sweep
				Number of points	Port powers
				IF bandwidth	Source attenuators
				Sweep type	Receiver attenuators
				Sweep mode	Test Set port map
				Error Terms: Directivity, Crosstalk, Source match, Load match, Reflection tracking, Transmission tracking

File Type Descriptions and Recall

The following describes each file type, and what occurs when the file type is recalled.

Instrument states can have the following suffixes: .sta, .cst, and .csa.

Common to all of the instrument state files is the state of the instrument including the quantity and content of channels, traces, windows, markers, limit lines, etc.

What is different about the instrument state files is the way they handle the calset - a calset is the set of data that results from having executed a calibration on a channel.

*.sta files

Contain ONLY instrument state information - NOT Cal data.
When recalled, they always replace the current instrument state immediately.

This instrument state file is saved without any calset data. You might choose to use this type of save file if you are concerned about disk space or specifically do not want to store calibration data that tends to have a shelf life. That is, calibrations become less accurate as cables move and temperature changes. Perhaps you want to force a new calibration when the instrument state is used.

*.cst files

Contain BOTH instrument state and a LINK to the Cal Sets. Learn more about Cal Sets.
The quickest and most flexible method of saving and recalling a calibrated instrument state.
Channels need not have cal data to save as .cst file.
When recalled, the state information is loaded first. Then the analyzer attempts to apply a Cal Set as you would do manually. If the stimulus settings are different between the instrument state and the linked Cal Set, the usual choice is presented (see Cal Sets). If the linked Cal Set has been deleted, a message is displayed, but the state information remains in place.
Because only a link to the Cal Set is saved, the Cal Set can be shared with other measurements.
If you perform a calibration and save the result to a calset called “MyCalSet”, then save a .cst file (for example, MyState.cst), then that file will have a reference to the name of the calset (“MyCalSet”).

If you redo the calibration and store the data again in MyCalset, then the next time you recall MyState.cst, your instrument state will use the new calibration data.
If you subsequently delete MyCalset, and then recall the MyState.cst, the resulting instrument state will not be calibrated as the calset no longer exists.

Note: Before saving a .cst file, be sure that a User Cal Set (NOT a Cal Register) is being used for the calibration. Cal Registers are overwritten with new data whenever a calibration is performed, and may not be accurate cal data when the .cst file is recalled. Learn more about Cal Sets.

*.cal files

Contain ONLY Cal Set information.
When recalled, the Cal Set is NOT automatically applied. Apply the calibration data to a channel as you would apply any Cal Set.
Learn about Recalling

These files are not instrument states. They are a set of calsets. When you save a .cal file, the contents will include every calset that is currently being used by the instrument. When you recall one of these files, the calset contents will be added to the list of of calsets available to the instrument. Recalling a .cal file does not change the active instrument state.

*.csa files

Contains ALL instrument state and the actual Cal Set; not a link to the Cal Set.
The safest method of saving and recalling a calibrated instrument state. However, the file size is larger than a *cst file, and the save and recall times are longer.
Channels need not be calibrated to save as .cst file.
The Cal Set that is saved could be a Cal Register or a User Cal Set.
Learn about Recalling

A .csa file is an instrument state and a collection of calset data. Every channel that has an active calibration (that is, has a calset selected and applied to the channel) stores its calibration data into the .csa file. For example, let's say you have a calset called “mycalset” and you are using that calset on channel 1. You save a .csa file called MyState. If you then perform another calibration and save that calibration to “mycalset”, the data in “mycalset” will not be the same as the calibration data in the MyState file. Consequently, when you recall MyState the old calset called “mycalset” will overwrite the new calset “mycalset”. When this is about to occur, you are given a warning. If this is a problem for you, you might prefer to use a .cst file.

Note: *.pcs files are the internal file format used for storing cal sets. These files should never be accessed or copied by the user.

Recalling Cal Sets

Recalling Cal Sets dialog box help

Both .cal and .csa file types contain whole Cal Sets. Because all channels are saved, there could be more than one Cal Set in either of these file types.

When these file types are recalled, a check is made to see if the incoming Cal Set GUID matches an existing Cal Set GUID. If it does, and if the rest of the Cal Set contents are different in any way, then both of these Cal Sets can NOT coexist in the analyzer. You are then offered the following choices:

Overwrite The incoming Cal Set will replace the existing Cal Set.
Duplicate (Only available with .cal recalls.) Because the Cal Set is not automatically applied, you can choose to apply either the original or duplicate Cal Set. The original Cal Set remains in the .cal file.
Cancel Abandon the recall operation.

Measurement Data Files

Measurement data is saved as ASCII file types for use in a spreadsheet or CAE programs.

Note: Before saving measurement data, always trigger a single measurement, and then allow the channel to go into Hold. This ensures that the entire measurement trace is saved.

Note: Memory traces can NOT be saved to any file type (PRN, SNP, CTI, CSV, MDF).

The following file types can be saved by the analyzer:

*.prn Files

Prn files have the following attributes:

Comma-separated data which can be read into rows and columns by spreadsheet software, such as Microsoft Excel. To avoid the "delimiting" dialog boxes, change the filename extension from .prn to .csv. Then open directly into Microsoft Excel.
Contain formatted and corrected stimulus and response data for the current active trace ONLY.
Are Output only - they cannot be read by the analyzer.
Applications and Cal Set Viewer data can be saved to *.prn files

Example:

"S11 Log Mag"
"Frequency (Hz)",	"dB"
3.000000e+005 ,	-3.528682e+001 ,
4.529850e+007 ,	-2.817913e+001 ,
9.029700e+007 ,	-3.216808e+001 ,
1.352955e+008 ,	-3.101017e+001 ,

.SNP Format (*.s1p, *.s2p, *.s3p. *.s4p, and so forth)

*.SNP file format, also known as Touchstone format, is specified by IBIS. See the Touchstone specification.
*.SNP file format is used by CAE programs such as Keysight's Microwave Design System (MDS) and Advanced Design System (ADS).
*.SNP data is saved using the File, Save Data As dialog.

Before saving measurement data, always trigger a single measurement, and then allow the channel to go into Hold. This ensures that the entire measurement trace is saved.

*.SNP files and other analyzer settings

.SNP data can be recalled and viewed on the analyzer, or read by the embed/de-embed functions.
To save SNP data with an external test set enabled, at the File, Save As dialog, select SNP File(*.s*p), then complete the "Choose Ports " dialog.
When Fixturing is enabled, all of the enabled data transforms (De-embedding, Port Z Conversion, and so forth) are applied to saved SNP files.
When Smoothing is applied to a trace, the smoothing is NOT saved when the format is Real, Imaginary (RI). Select a different format to save the smoothed data.
Segmented FCA data is saved to *.S2PX files. Scroll down or click here to learn more.
Learn about FCA parameters that are saved to an S2P file.
Noise Figure parameters and S-parameters can be saved to an *.s2p file. Learn more.
Balanced parameters can be saved to *.SNP files. See the "Choose Ports " dialog.
IMPORTANT - ALL valid data is saved using the same format and settings (trace math, offset, delay, and so forth) as the active measurement. This can cause the data that is saved for the non-active measurements to be dramatically different from the data that is displayed. For example, when saving an S2P file, if the active S11 measurement is set to Data/Mem (data divided by memory), then ALL 4 S-parameters are saved using Data/Mem. The memory trace that is used in the Data/Mem operation is the same as that used in the active (S11) measurement.

What is Saved

*.SNP data is generally used to gather all S-parameters for a fully corrected measurement.

The analyzer saves the data that is available on the channel of the active measurement.

File Type	# of Ports	# of S-parameters saved
*.s1p	1	1 S-parameter
*.s2p	2	4 S-parameters
*.s3p	3	9 S-parameters
*.s4p	4	16 S-parameters
...	...	...
*.SNP	N	N^2 S-parameters

If correction for a Full N-port cal is applied, then valid data is returned for all corrected s-parameters. Response cals will save uncorrected data.
If requesting less data than is available, the Choose ports for SNP data dialog appears.
If correction is NOT applied, the analyzer returns as much applicable raw data as possible using S-parameter measurements on the selected channel. Data that is not available is zero-filled. For example, if correction is NOT applied and the active measurement is S11, and an S21 measurement also exists on the channel, then data is returned for the S11 and S21 measurements. Data for S12 and S22 is not available and therefore returned as zeros in Real/Imaginary format. In Log Mag/Phase format, this appears as -200 dB and 45 degrees.

.SNP Data Output

.SNP files contain header information, stimulus data, a response data pair for EACH S-parameter measurement. The only difference between .s1p, s2p, and so forth, is the number of S-parameters that are saved.

The following is a sample of Header information:

!Keysight Technologies,E8362B,US42340026,Q.03.54

!Keysight E8362B: Q.03.54

!Date: Friday, April 25, 2003 13:46:41

!Correction: S11(Full 2 Port SOLT,1,2) S21(Full 2 Port SOLT,1,2) S12(Full 2 Port SOLT,1,2) S22(Full 2 Port SOLT,1,2)

!S2P File: Measurements:S11,S21,S12,S22:

# Hz S RI R 50

Note: Although the following shows Real / Imag pairs, the format could also be LogMag / Phase or LinMag / Phase

*.s1p Files

Each record contains 1 stimulus value and 1 S-parameter (total of 3 values)

Stim Real (Sxx) Imag(Sxx)

*.s2p Files

Each record contains 1 stimulus value and 4 S-parameters (total of 9 values)

Stim Real (S11) Imag(S11) Real(S21) Imag(S21) Real(S12) Imag(S12) Real(S22) Imag(S22)

*.s3p Files

Each record contains 1 stimulus value and 9 S-parameters (total of 19 values)

Stim Real (S11) Imag(S11) Real(S12) Imag(S12) Real(S13) Imag(S13)

Real (S21) Imag(S21) Real(S22) Imag(S22) Real(S23) Imag(S23)

Real (S31) Imag(S31) Real(S32) Imag(S32) Real(S33) Imag(S33)

*.s4p Files (and so forth...)

Each record contains 1 stimulus value and 16 S-parameters (total of 33 values)

Stim Real (S11) Imag(S11) Real(S12) Imag(S12) Real(S13) Imag(S13) Real(S14) Imag(S14)

Real (S21) Imag(S21) Real(S22) Imag(S22) Real(S23) Imag(S23) Real(S24) Imag(S24)

Real (S31) Imag(S31) Real(S32) Imag(S32) Real(S33) Imag(S33) Real(S34) Imag(S34)

Real (S41) Imag(S41) Real(S42) Imag(S42) Real(S43) Imag(S43) Real(S44) Imag(S44)

.S2PX Data Output

*.S2PX files are used for Segmented Mixer Data. Learn more.

The following ADDITIONAL columns precede parameter data:

SegIndex,InputFreq,OutputFreq,LO1Freq,InputPower,LO1Power, <parameter data>

Choose ports for SNP File dialog box help

This dialog appears when any of the following conditions exist while attempting to save data to an *snp file:

you request less data than is available
you want data for more than 4 ports
a balanced measurement is active

Number of ports Select the number of ports for which data will be saved.

The following buttons appear ONLY when a Balanced measurement is displayed.

Normal Click to save normal (single-ended) port data.

Mixed Mode Click to save balanced (logical) port data. Choices are based on the topology selection for current active parameter:

SE-Bal: Choose from S1, D2, C2 (Single-ended port 1, Differential port 2, Common port 2)
SE, SE, Bal: Choose from S1, S2, D3, C3 (Single-ended port 1, Single-ended port 2, Differential port 3, Common port 3)
Bal-Bal: Choose from D1, C1, D2, C2 (Differential port 1, Common port 1, Differential port 2, Common port 2)

For example, with SE-Bal topology, choose 2 ports, S1 for first, and D2 for second. The following 4 parameters are saved: Sss11, Ssd12, Sds21, Sdd22.

Arrow buttons Click to Add or Remove ports from or to the following columns:

Available Ports All test set ports are listed. There may NOT be valid data available for all of these ports. Learn more.

Chosen Ports When OK is clicked, SNP data is saved for these ports.

OK Becomes available when the number of Chosen ports = the Number of ports to save. Click to save to SNP file.

With Number of ports = 2, .s2p data is saved; with Number of ports = 3, .s3p data is saved, and so forth. Learn more about SNP files

.cti CitiFiles

Citifile format is compatible with the Keysight 8510 Network Analyzer and Keysight's Microwave Design System (MDS).

You can do the following using citifiles :

save the active trace, or all traces.
save formatted or unformatted citifile data

To save Formatted *.cti data

Click File then Save Data As
Select Citifile Formatted Data (*cti)

The above image is a Citifile opened in Notepad. There are two traces in separate channels - one is an FCA trace. Each trace has 3 data points. The save settings = Displayed Traces Content, and Auto Format.

Format is identified by DBANGLE (log mag), MAGANGLE (Lin Mag), or RI (real, imaginary - NOT shown)

On the data access map, Formatted data is taken from location 2 or 4.

To save Unformatted *.cti data

Click File, then Save Data As
Select Citifile Data Data (*cti)

On the data access map, Unformatted data is taken from the block just before Format.

Citifiles can be recalled and viewed in the analyzer. Learn more.

*.csv Files

Note: 2D Gain Compression data is saved as *.csv files using a different format than shown here. Learn more.

CSV files are read by spreadsheet programs such as Microsoft Excel.

To save *.csv files:

Click File, then Save Data As
Under Save as type, select CSV Formatted Data

*.csv files contain: header information and the following Comma-Separated Values.

Stimulus data
Data pairs for EACH S-parameter

*.mdf Files

MDIF files are compatible with Keysight ADS (Advanced Design System). Learn more at the Keysight website.

To save *.mdf files:

Click File, then Save Data As
Under Save as type, select MDIF Data

*.mdf files contain: header information and space-separated data:

- Stimulus data
- Real and Imaginary data pair for EACH S-parameter measurement

Define Data Saves

Note: Although these settings are still supported, they are no longer necessary to save data files. The Save Data As dialog box contains these settings.

How to select Define Data Saves
Using front-panel hardkey [softkey] buttons	Using Menus
Press System then [Configure] then [More] then [Preferences] then Data Saves	Click Utility then System then Configure then More then Preferences then Data Saves

Define Data Saves dialog box help

Note: Although these settings are still supported, they are no longer necessary to save data files. The Save Data As dialog box contains these settings.

The following settings survive an Instrument Preset and Shutdown.

CitiFile, CSV, and MDIF Contents

Determines what is saved to a .cti file.

Auto - Saves the active trace. Additional traces are saved if correction is ON. For Full 2-port calibration, 4 traces are saved; for Full 3-port calibration, 9 traces are saved, and so forth.

Single Trace - Saves the active trace.

Displayed Traces - Saves all displayed traces for all channels.

Citifile and CSV Format

Auto - Data is saved in LogMag or LinMag if one of these is the currently selected display format. If format is other than these, then data is saved in Real/Imag.

LogMag, LinMag, Real/Imag - Select output format.

The imaginary portion for all LogMag and LinMag data is saved in degrees.
Real/ Imag data is never smoothed.

SnP Format (.s1p, .s2p, .s3p)

Learn more about SnP files.

Auto - Data is saved in LogMag or LinMag if one of these is the currently selected format. If format is other than these, then data is saved in Real/Imag.

LogMag, LinMag, Real/Imag - Select output format. The imaginary portion for all LogMag and LinMag data is output is in degrees.

Manage Files without a Mouse

The Manage Files dialog box is designed to be used from the front panel. It performs the same function as Windows Explorer, but can be used without the use of a mouse or keyboard.

Manage Files dialog box help

Recall Opens a Network Analyzer file already stored in memory.

Rename Renames a file that is selected in the open folder.

Delete Removes a selected file from the open folder.

Delete All Removes all files of the file type selected that appear in the open folder.

New folder Create a new folder and give it a name.

How to Save Instrument State and Calibration Files Use one of the following methods:
Using front-panel hardkey [softkey] buttons	Using Menus
Press Save then [Save], [Save As], or [Auto Save]	Click File then Save or Save As
Learn all about Instrument State files. Save Immediately saves the instrument state and possibly calibration data to the filename and extension you used when you last performed a Save. This file will be overwritten the next time you click Save. To prevent this, use one of the following methods. Save As Starts the Save As dialog box. Auto Save NOT available from the Menu. Saves state and calibration data to the internal hard disk in the c:\users\public\network analyzer\documents folder. A filename is generated automatically using the syntax "atxxx.csa"; where xxx is a number that is incremented by one when a new file is Auto Saved.

How to Save Measurement Data Use one of the following methods:
Using front-panel hardkey [softkey] buttons	Using Menus
Press Save then [Save Data As]	Click File then Save Data As
Save Data As Saves the current trace(s) to the specified type of file. Note: This dialog now contains the settings previously selected from the old Define Data Save dialog.