Generate Smith chart on the computer with linSmith

I studied Electrical Engineering at West Negros College but I can't recall using a Smith chart for transmission line calculations and other uses. Instead we use our slide rules and the just coming of age Casio fx-102 (with micro fluorescent glow tubes) or a TI-58 for some lucky classmates, for computing directly the equations involving hyperbolic functions.

Nevertheless, in this modern era, a Smith Chart is still a very useful graphics method for getting a quick grasp of the effects of system design parameters on constant or varying frequency. In this entry we concentrate on linSmith a FREE software for drawing Smith Chart and diagrams superimposed on it by the program. I mean, you don' have to manually plot points on the chart itself, the program will do it for you. Luckily the linSmith program is comprehensive and comes with usefule examples for self study. You can always do self-education after you graduate!

Here is a description from the Ubuntu package which is at version 0.99.7-1,

• Definition of multiple load impedances (at different frequencies)
  
• Addition of discrete (L, C, parallel and series LC, and transformer)
  and line components (open and closed stubs, line segments)
  
• Connection in series and parallel
  
• Easy experimentation with values using scrollbars
  
• A 'virtual' component switches from impedance to admittance to help
  explaining (or understanding) parallel components
  
• The chart works in real impedances (not normalized ones)
  
• Direct view of the result on the screen
  
• Ability to generate publication quality Postscript output
  
• A 'log' file with textual results at each intermediate step
  
• Load and circuit configuration is stored separately, permitting several
  solutions without re-defining the other
  

Ubuntu puts the LinSmith package in the desktop menu at Applications/Other/ (together with gretl, Geomview, and Snappea.Here is a pic of the software:

linSmith has a developer homepage at John Coppens. The developer even recommends you compile from the latest sources! The latest version is already at 0.99.12 making the Ubuntu package out of date.
An Introduction and tutorial are also available from the homepagepage.

Wikipedia has an entry on Smith Chart.

We will hopefully write articles on problemsolving with linsmith in the future, as one of our aims is to present an engineering review in our blogs.