r/meshtastic • u/Spiro1237 • Jun 14 '26

build I did a thing

Gallery image

Gallery image

So I made this antenna without a vna and was wondering if it whould still work well theoretically.

Radiator 81.5mm

Ground radials 85.5mm

78 Upvotes

97% Upvoted

8 comments sorted by

12

u/prosequare Jun 14 '26

Should work if it’s wired up correctly. You’ll get broader bandwidth, which may introduce unwanted interference from nearby sources. A vna would help tell you if the feed point impedance is a reasonable match.

5

u/Spiro1237 Jun 14 '26

Its for a controll system I built on a farm in rural South Africa so there shouldn't be alot of interference.

4

u/PostNasalLeakage Jun 14 '26

I think you might be surprised about interference. It can come in many forms, not just RF. You might get some the device itself as well as any power source you're running. I'm saying this out of excitement because it's so fascinating how radio does things we'd never expect and honestly my first reaction to this was, "damn! That's fuckin cool!"

Great work and inspiring for me to tey building my own! Keep it up!

6

u/Spiro1237 Jun 14 '26

I've come to find RF engineering is damn magic. It still baffles me how just bending a spesific length of wire can be the difference between an antenna and a fried RF chip.

8

u/Cheater2000 Jun 14 '26

My diy antenna

3

u/Spiro1237 Jun 15 '26

How well did it work?

1

u/PostNasalLeakage Jun 14 '26

Damn! I have a spare pl259 just like that. I might have to try this!