By Chip Coker KD4C
Have you always thought that antennas were “magic”? Well hopefully you understand that there is actual physics involved in the way antennas work, even if it’s not obvious to us. In the past, RF engineers had to perform complex calculations by hand to estimate the performance of even simple antennas, but now with the advent of computer modelling software, the average ham can create a fairly complex computer model of simple ham antennas and see in great detail the expected performance of the antenna. Is it perfect? No, but it’s surprisingly good…
There are two free modeling softwares that I’m aware are used frequently for antenna modeling: MMANA and EZNEC (EZNEC was a paid program and had several free variations, but EZNEC is now free). MMANA is simple to use and provides easy to understand graphs. EZNEC is feature rich and can be used for very detailed models.
Callum M0MCX has a bunch of YouTube videos that show him modelling various antennas and using MMANA (plus he’s pretty entertaining).
Antenna Modelling for Complete Beginners – Callum M0MCX
Dave Casler shows how to use modelling software to compare antenna designs.
4NEC2 is one of the simplified variations of the full EZNEC software based on the NEC2 engine.
These videos are only a sample of what’s available. There is plenty of help so you can learn how to master and use these helpful modelling programs and reduce the “magic” in your antennas.
MMANA – http://gal-ana.de/basicmm/en/ (basic version is still free)
4NEC2 – https://www.qsl.net/4nec2/ (also based on the NEC2 engine)
EZNEC extended manual is available on ARRL site: http://www.arrl.org/files/file/Antenna%20Modeling%20for%20Beginners%20Supplemental%20Files/EZNEC%20Modeling%20Tutorial%20by%20W8WWV.pdf