this post was submitted on 15 Mar 2025
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cross-posted from: https://sh.itjust.works/post/34507515

How do you test your antenna idea? Well, our approach was to get a portable network analyzer that can show received dBm, put a commercial antenna on it, and strap the whole thing to a PVC pipe (for insulation and to get repeatable height). Then, zip-tie a cough drop to the PTT of a walkie talkie set to low power, so that it transmits continuously.

Now you can walk around your contraption with your Drain Pipe of RF measuring, and get a (rough qualitative) idea of how the pattern looks like. Much to my surprise, it actually worked.

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[–] [email protected] 8 points 1 week ago (1 children)

I love weird antenna. My balcony itself is a surprisingly good radiator.

[–] [email protected] 9 points 1 week ago (1 children)

Everything is an antenna. Unless you want it to be an antenna, then nothing is.

[–] [email protected] 3 points 6 days ago

Even trees can be antennas

[–] [email protected] 4 points 1 week ago (1 children)

I know how it's done in the lab using a two-port VNA, but your method can also work to find the radiation pattern. Will just be a bit challenging when it comes to canceling out noise

[–] [email protected] 6 points 1 week ago (1 children)

We don't have a lab :P

Also, to measure the far field, you'd need a non-trivially-large anechoic chamber, right? I figured an open field is the next best thing, and the park is the next best thing to an open field...

[–] [email protected] 2 points 6 days ago

Yeah. Easier to do with mm-wave antennas haha