Smith Charts


SimSmith version 10.2 is over a year old and has proven to be very stable.  However, that does not mean SimSmith has not been under development.  However, the new feature have more warts and glitches than I prefer the casual user experience.  As a result, if you find SimSmith 10.2 adequate to your needs I highly encourage you to stay with it.  BUT, if you are an adventurous user I invite you to drop me a note.  I’ll periodically ship you a ‘beta’ quality ‘drop’ with documentation.  If you find it useful, great.  If not, drop me a note why and I see what I can do.  I’ll maintain a mailing list on my development machine.  Mail to

If you are just getting started with SimSmith, please (PLEASE?) watch at least two videos:  SimSmithV7 (parts 1 and 2) and IntroToSmithChart.

SimSmith version 9 is a major update to SimSmith.  SimSmith now comes as a package tailored to each run environment: “.exe” for Windows, “.dmg” for mac OS X, and ‘.tar’ for Linux.  The package contains SimSmith, a Java Runtime Environment, and all the documentation.  This makes the distribution much larger but also much easier.

This move to packages has some draw-backs.  For example, Windows XP opening the documentation under the ‘help’ menu uses ‘explorer’.  If you don’t have explorer working, you won’t be able to read the documentation on XP.  On other platforms, SimSmith uses the ‘default browser’ for displaying the documentation.  Also, older versions of OS X seem to have some trouble with ICONs on the desktop; SimSmith works but the Icons are not displayed properly.

The software I’m using to create the bundles does not work well on legacy operating systems.  If you can’t get the ‘exe’ or the ‘dmg’ or the ‘tar’ working, please try the ‘.jar’.  Using the ‘.jar’ requires that you have a JRE installed.

Updated versions of the documentation can be found in the ‘help’ menu bar once you have SimSmith up and running.

Here are the links to the various system dependent SimSmith distributions:

        There have been some problems with the OSX packages, specifically the 64 bit versions.  If you can’t seem to get them to run you might try the 32 bit version.  If that doesn’t work, please go to Oracle and install an up to date JRE.  Then, use the SimSmithXpX.jar to run SimSmith.  That seems to work fine everywhere BUT you don’t get the spiffy icons on your desktop...

           Version 10.2 packages                                Notes:
        ReleaseNotes.pdf                latest copy of release notes.
        SimSmith-windows32.exe    uses ‘explorer’ to examine documentation.
        SimSmith-macos32.dmg      may download and install JRE 1.6 if necessary.
                                                     Has problems with reporting program name on older OS X.
        SimSmith-linux32.tar            No Icons yet
        SimSmith-linux64.tar            No Icons yet
        SimSmith10p2.jar                 Uses JRE 1.6 or 1.7 or 1.8, JRE 1.5 has problems.

NOTE: Apple, in its infinite wisdom, has decided to protect you and created a technology called ‘gate keeper’.  Anything running gate keeper (Mavericks at least) will stop you from running SimSmith unless you turn off GateKeeper during the installation.  This is done by going to ‘System Preferences’, ‘Security and Privacy’ and selecting ‘Allow Apps downloaded from’ “Anywyere”.  As far as I know, once the installation is complete you can raise the protection levels to where-ever you want.  GateKeeper only oversees the installation process, not each invocation.  I do recommend setting GateKeeper back up.

A Video of how to do this is here:  SimSmithUnderMavericks.mp4

A few users have run into other problems downloading onto OS X for a second time.  The scenario seems to be: mount the ‘.dmg’, drag the SimSmith app to the desktop (or where-ever), run SimSmith, JWrapper starts up but then silently fails.  If you check the log you’ll probably find error messages concerning renaming of files or changing the executable or what-ever.  You can avoid this problem by using ‘terminal’, and executing the following commands:
            cd ~/Library/Application\ Support
            rm -rf JWrapper*
This removes the vestiges of previous ‘installations’.

Some older releases are here:
              SimSmith9p6.jar  SImSmith-7.8.jar SimSmith-7.4.jar  SimSmith-6.4.jar 
              SimSmith-5.7.jar  SimSmith-4.14.jar  SimSmith-5.4.jar 

If you download SimSmith, please consider joining  the Yahoo Group “SimSmith”.  This will allow you to make suggestions, share techniques and be notified of bugs and releases.

Here’s an old Primer: SimSmith Primer.pdf  Newest one is in the distribution under ‘help’.
Here’s the article in QRP Quarterly: QRParticle.pdf  

Here is the syntax of the F block and the ‘load file’ format:  VenerableAppendix.pdf  See ‘help’ for more up to date version.

Here are some example impedance files:

I try to write down some of the info on SimSmith but I find it difficult to convey the feel of an interactive program using text.  Rather, I make short (10 to 20 minute) videos.  Generally, if there is a new feature I make a video.  As SimSmith evolves, I don’t go back and redo the videos.  This makes the videos obsolete when it comes to tool layout.  The videos are still worth watching because they show what features are available even if subsequent versions moved them around. 

Many of these tutorials were made some time ago using an older version of SimSmith.  You can use this version of SimSmith to work through the older tutorials:  SimSmith-4.14.jar    Basic introduction to SimSmith. View this first.     Expanded Intro to SimSmith Basics using Version 7.     Expanded Intro to SimSmith Basics using Version 7.    Advanced Generators and the Function Block.       I look at impedance matching over a range of frequencies.
                                    (Here’s the load model I used in Tutorial2:80mDipole.txt)       I add a feed line and explore chapter 9 of the Antenna Handbook.       I use SimSmith to design a better Dummy Load.       I describe some features of SimSmith... and some idiosyncrasies.       A detailed look at SimSmith’s Function Block.  See the Introduction 
                                        to version 7.1 above for a more up to date information.       Transformers, reference traces, S blocks and Session Restore.
                                       (note that the ‘’ has been moved to the
                                        user’s home directory as of 4.13).        Introduces features new to version 5: resizing menus, sweep control
                                    and plot signal selection.        Explains changes made in version 6 and introduces new features.

SimSmithV9.mp4        Highlights of version 9: drag and drop and the N block... 

    10p2    12-2-14
            Better Smith and square chart zooming and panning, fixed a bunch of
            ‘bugs/misfeatures’, added MMANA support, fixed a few internal bugs with N
            and F blocks, added multipliers to xMtch, useZo, etc, added ‘curves’ to N and F
            block plotting, removed Scattering Parameters square chart (lack of interest).
            See ReleaseNotes.pdf for details.

    9p9    2-13-14
            Fixed lots of little problems.  Changed square chart zooming to be ‘continuous’,
            added ‘click/drag’ for panning the Smith chart (click well away from any trace and
            drag the chart).  Click/drag panning for Square chart, click on axis and move ti up
            or down.  Added generic ‘exception handler’, please follow directions if you run into
            a problem.  See ‘help/latest release notes’ for more details.
            THIS VERSION HAS KNOWN PROBLEMS with Windows VISTA.  So far, no one
            has stepped forward to help debug it.

    9p8    1-28-14
            Fixed a problem with the Power Lost report and plotting in the Square chart.
            Fixed problem with matrix evaluation... seems I had broken it after alll...
    9p6    1-22-14
            Fixed a few system dependent startup problems, improved matrix evaluation
            (and hopefully didn’t break it, please be wary).
            THIS VERSION HAS KNOWN PROBLEMS with Windows VISTA.  So far, no one
            has stepped forward to help debug it.

    9p5    1-18-14 
            MAJOR CHANGES: added file drag and drop, got undo to work better, added
            Netlist block.  Improved Smith chart zooming, cleaned up graphics.  Packaged
            in the JRE and all documentation.  See ‘help/release notes’s for more details.
            Removed ‘printing’ and substituted writing (and capturing) screen images.  Captures
            don’t work on OS X running java 7 so the option to include ‘capture’ in the top
            toolbar must be enabled in the ‘file/preferences’ menu.
            There are a few esoteric problems on XP an OS X 10.5.8 which probably
            won’t be fixed.
            Linux distribution hasn’t has much test mileage. See SimSmithV9.mp4 above.
            VERSION 9p5 can generate .ss files incompatible with earlier versions.  It now
            names the backup file in a version specific way.  You’ll get warned about missing
           THIS VERSION HAS KNOWN PROBLEMS with WIndows VISTA.  So far, no one
            has stepped forward to help debug it.

    8.3    MAJOR CHANGES.  This release reworked significant parts of the computational
            internals.  Use this release only if you’re confident you will notice any bad behavior.
                The release notes are extensive and are here: Version8ReleaseNotes.pdf
            Here is the ‘jar’ file: SimSmith-8.3.jar I won’t package up version 8 until I (and others)
            have used it for a while and it proves reasonably reliable.
            VERSION 8.3 GENERATES “.ss” files incompatible with earlier versions
            of SimSmith.  To go back you’ll need to delete “”
            in your home directory.

    7.8    Cosmetic changes.  Also added AC6LA transmission lines to F block.  Component
            labels are no longer changed when you re-arrange the elements in the circuit.

    7.7    Added support for AC6LA style transmission lines.  Changed warning box to
            make it more readable.  Fixed graphing problem in SWR plots.

    7.6    Jan 8, ’13    Added support for ‘meters’ (at last).  Changed the sweep menu to
            make its operation a little easier to explain.  Added a ‘PATH/SWEEP’ button to
            the Smith chart.  Please see SimSmith primer (above) for details.

    7.4    Dec 5, ’12    Minor fixes in graphics display.  Added ‘wrappers’ for windows,
            and OSX.  No wrapper yet for Linux.

    7.2:    Nov 12, ’12  Fixed several bugs involved with equation editing.

    7.1    Improved Function block support.  Added equations to the ‘Generator’ block.
            See VenerableAppendix.pdf for equation Syntax.

    7.0:  Drag tuning deserved its own major release number.  Addition of preferences to
            set things like default Q values for inductors and capacitors.  Had to play around
            (Again) to get international number formats to work.  Please report any problems.
            Here are some cursory release notes: SimSmith 7 Release Notes.docx


    1.1    changed to ‘clicking’ in charts to show information
    1.4    fixed problems with “Save” and “Load” for transmission line segments
    1.6    added support for reading “cocoaNEC” nec2 output files for ‘loads’.
            added ‘db’ indicator for “powerIn” in SWR chart.
            fixed a few cosmetic things.
    1.8   (and 1.7) fixed cosmetic things.  The big ones were ‘scan frequency’.... 
            the frequency didn’t always fit and the most significant digits were dropped.
    1.9   A few cosmetic changes, fixed calculation of Q for inductors.
    1.11 Just cosmetic again.

     2.0  I had problems with Ubuntu performance (very sluggish editing) in
            early releases, this release should fix any such problems.  My sincere
            thanks to Eldon Brown (WA0UWH) for providing testing for the rewrite.
            This effort required a complete rewrite of the “Smith chart” graphic.
                I added three features:  a button to hyperlink you to this page,  an ‘x’
            at the ‘generator frequency’ on the SWR plot, and a vertical marker at the
            report frequency, also on the SWR plot.
    3.3   Yes, lots of work in between.  I added ‘standard values’ for resistors, capacitors,
            and inductors.  There are built in ‘standard values’ and you can load your own
            standard value files as well.  There are three new tuning buttons:
            “previous”, “closest”, and “next” which are immediately below the old tuning
            buttons.  There are also three new buttons for loading your own ‘standard values’.
            The built-in standard values for resistors is a 5% chart I fond on the web.
            The SimSmith Primer document above has been updated to show the file format
            which is pretty obvious.  Here’s an example:  SimSmith.RES
    3.4   A quick update to add a ‘Pin’ field to the schematic components.  Assuming 1 watt
            is delivered by the generator, “Pin” indicates how much power makes it to the
            component.  For a lossless network then, the Pin at the load should say “1”.
            Practical circuits will have a power at the load of less than 1.
    3.5   Fixed version string... 3.4 said it was version 3.5 (sigh).
    4.2   Added a ‘library’ function, added a few components (including a transformer),
            changed ‘save/load’ operation, and added a ‘print’ function.
    4.3   Added support for W7AY’s AAPlot Mac OS-X application.  SimSmith can now
            read the impedance data set from ‘Rig Expert’ antenna analyzers.
    4.4   Fixed some cosmetic bugs.
    4.8    Fixed various cosmetic and operational esthetics.  Introduced the support for
            touchstone file formats for Scattering Parameters.    You can specify the load
            using a touchstone “.s1p” file.  (SimSmith looks at the extension and, seeing
            “.s1p” will attempt to read the file as a touchstone s1p file.
                I also introduced the “S” circuit element.  You can specify the scattering
            parameters for the S block using touchstone “s2p” files.  Only s2p “Scattering
            Parameter” formats are supported, no ABCD or Y or Z parameterization yet.
            This release took lots of editing so I won’t release it as main line for some time.
    4.9   I cleaned up a couple of bugs in S blocks.  I added the ability to reverse S blocks.
            I added the ability to change how transformer traces are drawn on the Smith Chart.
    4.10 I put in the code to ‘tolerate’ Version 2 of the touchstone files.  Basically, I simply
            confirm that the options are what would be supported by version 1.1.
    4.12 April4-2012
            This was a major undertaking and should probably have been 5.0!  SimSmith can
            now read in load files and display them directly on the SWR and Smith charts.  Any
            of the supported load files can be used.  You can also write touchstone S1P files
            so that you can save a circuit analysis for future reference.  
                I COMPLETELY CHANGED THE DISK FILE FORMAT.  I believe I left
            in the ability to read old files but all files are saved in the new format.
                I changed transformers so there are two views, one for coupled inductors with
            variable coupling and one for a simple transform with k assumed to be 1.  In this
            second transformer you can specify the turns ratio directly.
                SimSmith now keeps a copy of your circuit on the disk called
            “”.  This file is updated whenever you make a circuit change.
            It is read in when SimSmith starts up so you can resume your session as it was
            when you exited.  You can load a different file at startup if you invoke SimSmith
            from the command line.  On OSX you would type
                        java -jar SimSmith-4.12.jar filename
            I highly recommend you glance over the SimSmith Primer (near the top of this
            page) and look through the video “NewTo4.12” to get an overview.
    4.13 April-7-2012
            Moved ‘’ to the user’s home directory.
    4.14 Fixed circuit load problem.
    5.0    May 21, 2012....
            This was a substantial rewrite of the whole user interface.  Nearly everything is
            scaled correctly so things remain readable even when small.  The menus can be
            resized to make room for bigger circuits or bigger charts.  Version 5 provides
            much better control of what gets plotted and allows for sweeping of variables
            other than frequency.
    5.1    May 22, 2012
            Fixed SWR report in SWR Chart.
    5.3    June 18, 2012
            Added a ‘notes’ block.  Click on “file>show Notes Block”.  It should appear around
            the tuning buttons.  If not, click “help>recover Notes Block”.  Move the block by
            dragging the upper left corner, resize by dragging other corners.
                You can now use ‘load’ files to control sweeping.  The frequencies specified in
            the load file are used exactly... no interpolation is performed.  When you specify
            a load file, it is generally added to the sweep menu.
                The SWR and Smith charts are now both shown: one ‘large’ and one ‘small’.
            Clicking on the small one makes it large....
                Added the ‘frequency’ to traps.  Modifying the frequency or the capacitance will
            update the inductance.  Updating the inductance will change the frequency only.
                Added ‘Z’ blocks.  You can specify the value of Z explicitly or using a load file.
                Changed the precedence in the ‘F’ block a little to make it possible to write things
            like “10+10j” instead of “10+j10”.  As usual, if you see unusual behavior, fully
            parenthesize your equation.
    5.4    June 19, 2012
                 Added the “Generator” as a plotting option.  Best to select it when plotting the
           final result.
                Fixed a bug in the ‘sweep generator’ menu editor.
    5.5    June 26, 2012
                Added transformer “interwinding” capacitance.  Reworked code for transformer
            model.  Please report an problems.
                Fixed “PGain” plotting and reporting problem.
                Fixed “Load Component” R and X reporting.
    5.6    July 22, 2012
                Fixed bug where SimSmith crashed if an ‘reference’ file was missing on
    5.7    Aug 12, 2012
                Fixed problem reading nec2 files (which took forever), added support for nec4.1
            and nec4.2.  Fixed problem with “f” suffix in numbers (femto).  The ‘f’ was ignored.
    6.2    Sep 8, 2012
                Fixed a variety of bugs with Q and transmission line losses.
                Show parameters being edited as ‘pink’ until edit is complete.
                Added user selected scales to Power Gain and SWR plots.
                Added magnification for Smith chart.
                Added ‘Q’ arcs in Smith chart.
                Added new generator models: ‘fixedV’ for power amps with no matching, ‘xMtch’ for
           power amps with a transmatch, and ‘useZo’ for filter design.
                Moved ‘load files’ from components to sweep menu only.
                Added more print options for generating documentation.  Now everything is scaled
            to fit the print page.  Useless parts of the screen are not printed (things like plot
            menus and hidden references).
                Added ‘z’ to the Function block so you can access the working impedance.
                Added a ‘Notes’ block... click on ‘file’ ‘show notes block’...
    6.4:    Sep 18, 2012
            Fixed problem with commas as decimal separators.
            Improved sweeping speed.
            Added new ‘Z’ operator... lets you tune and compare multiple circuits at the
                same time.
            Fixed bug in transformer where SimSmith crashed if you switched to ‘simplified’.