On the G4FQG Software page, R.J. Edwards says, “There ARE such things as free lunches,” and then goes on to prove that point by offering a bunch of “original, high-quality, radio engineering/modelling programs” for nothing.
There’s lots of good stuff here, including programs that will help you model and design:
- loop antennas
- helical antennas
- loaded vertical antennas
- transmission lines
- impedance matching circuits for end-fed half wave antennas
- etc., etc., etc.
One of the cool things about these programs are that they’re all DOS programs, and the downloadable files are all small .EXE files that you can run directly after downloading.
Antenna modelling has been on my list of ham radio to-do list for quite some time now, but I’ve been putting it off because getting into it usually means downloading a complicated program with a relatively steep learning curve. With these simple programs, I may actually get around to doing it. The one I’m most interested in at this point is VERTLOAD, which models base-fed vertical antennas with load coils at any height.