SimSmith is written in Java.  To run it you must install the Java Runtime Environment.  Version 2.0 and onward REQUIRE JRE 1.6.  See my page on “Java Runtime”.

Here is my code: SimSmith-4.14.jar

Please review my page on Downloading Java Programs.

I have chosen to release SimSmith under the “Modified BSD” license.  The short form is, you can use my code in any way you might see fit but I don’t promise its worth using for anything.

I expect to post the source code on Source Forge some time in the future... just haven’t the

time right now.

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 a Primer: SimSmith Primer.pdf

Here’s the article in QRP Quarterly: QRParticle.pdf

Here is the syntax of the F block and the ‘load file’ format:  SimSmithAppendix.pdf

Here are some sample ‘load’ files:   EZNECexample.txt AIMexample.txt miniVnaProFRX.txt cocoaNEC.txt RigExpert.aaplot

I have made a few unpolished videos about how to use the Smith Chart.  I keep adding small videos over time.  I’m sorry these are rather large.  I hope to reduce their size as I understand video rendering a little better.  Each video is around 10 minutes long.

PLEASE NOTE: I have changed SimSmith’s behavior when the mouse cursor is in the Smith Chart and the SWR Chart.  You now have to hold the mouse button down in order to see the impedance and Power In information.  This change was made in SimSmith-1.1.  Note that tutorials 1-4 are out of date where this is concerned.

Unfortunately, when I created these files I used an encoding from Quicktime called “animation”.  This encoding makes the files MUCH smaller but,  apparently, only Quicktime supports this encoding.  Please go get a quicktime for your machine.  I’ll re-encode these with a normal encoding compatible with Windows some time but for now... Sorry... gotta use QuickTime.

For those who can’t (or wont) get Quicktime, my “Transient Files” directory has these videos in a “.avi” format.  They are very large but they work on most systems and maintain the crispness of the original.  Be prepared to wait for a long download.

IntroToSmithChart.mov I introduce Sim Smith using impedance matching as an example.

SmithTutorial2.mov       I look at impedance matching over a range of frequencies.

                                    (Here’s the load model I used in Tutorial2:80mDipole.txt)

SmithTutorial3.mov       I add a feed line and explore chapter 9 of the Antenna Handbook.

SmithTutorial4.mov       I use SimSmith to design a better Dummy Load.

SmithTutorial5.mov       I describe some features of SimSmith... and some idiosyncrasies.

SmithTutorial6.mov       A detailed look at SimSmith’s Function Block.

SmithTutorial7.mov       Transformers, reference traces, S blocks and Session Restore.

                                       (note that the ‘lastSimSmithCircuit.ss’ has been moved to the

                                        user’s home directory as of 4.13).

RELEASE NOTES:

    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

            “lastSimSmithcircuit.ss”.  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 ‘lastSimSmithCircuit.ss’ to the user’s home directory.

    4.14 Fixed circuit load problem.