Easy Yagi Design for Hams
WA1UQO writes:
So you missed the meeting? Join the RARC so you don't miss any more!RARC members may remember the program on
roll-your-own baluns given by John Portune,
W6NBC. For the January 2024 meeting he is
back via Zoom from the west coast to show us
how to design Yagi* antennas.
John’s comment: “Hams tend to fear building their
own Yagi beams, thinking that only
professional radio engineers can design Yagis.
The equations seem way too complex and the
many on-line Yagi calculators all conflict with
each other, and they do not know which one to
trust. GOOD NEWS. Ham yagi design is really
simple as this presentation shows. Only three
easy to remember no-math, no-calculator rules of
thumb yield results that can't be
distinguished from yagis designed with the
calculators and the fancy math.”
The presentation is online at https://rarclub.net/ , well it is, and points to this YouTube of the January RARC Meeting:
https://youtu.be/I70tGmmqPuY?si=2rqtrr-wYk4Gkt9x
So what did he say? Really easy? Yes.
W6NBC says it comes down to just 3 simple rules:
1. Cut the driven element dipole to the desired frequency.
2. Other elements length differ by 5% from this -reflector 5% more, directors 5% less.
3. Space every element at 0.2λ apart.
You're done! Don't waste time with fancy math or too many directing elements; they don't make the didliest bit of difference. -Well, not that you'd notice.
Construction tips: use rectangular booms rather than trying to fix to round pipes. Wood works well and is easy.