As a ham radio operator, aside from writing software, I have always been an antenna freak. I'm not one to spend a lot of money on a commercial antenna that I can build from parts laying around or found at the local hardware store. Recently I was playing around with a 5/8 wave vertical antenna and needed to construct a matching unit. I spent more time researching the information I needed to build the matching unit than I did actually building the antenna, matching unit, and testing the thing.
That got me to thinking ( a dangerous thing according to my XYL ), why not build a simple program that would allow others to use those formulas found strewn across the following references:
Practical Antenna Handbook, Joseph J. Carr. ISBN: 0-83069-270-3
ARRL Antenna Handbook, American Radio Relay League, ISBN: 0-87259-206-5
Antenna and Techniques for Low-Band Dxing, John Devoldere, 0-87259-466-2
The program consists of various utilites from antenna calucations, impedance matchting and tramission lines to Class E Amplifiers. Here we can compute the values for an inverted L network that will allow you to match the 50 ohm output of the radio or Source impedance to the low impedance normally found in a vertical antenna. All that is now required is to locate a 150pF capacitor and wind a coil of 0.13uH and you should have a pretty good match to the antenna.
Need a 5/8 wave vertical for 10 meters, here we can compute the necessary length in the units of choice. This will get you into the ballpark, and your handy-dandy MFJ antenna analyzer will get you into resonance and produce the load impedance for calculating the matching unit.
If you have ever had a burning need to get a bearing and distance to Drumsite on Christmas Island along with the local sunrise and sunset time, this is the place. You even get a Google overhead shot of the location. ( NOTE: The data for this is stored on my Web Site and will require an internet connection to access )
Update 8/28/2023: This is an Update to the previous application Antenna Calc from some years ago. It is a complete redevelopment with a different development environment and will allow this program to run on just about any flavor of windows. It will also run under Linux and Mac with the WINE environment installed. There is now an option in the Help menu to check for updates. That is partially finished. If it tells you there is and update, you will need to return here to download the updated install file. I am still working on the rest of that options and should have it available with the next update.
Over time, I will be adding additional utility tot eh program as I get them developed and debugged.
