How to turn an old Wi-Fi router into an access point
https://www.cnet.com/how-to/how-to-turn-an-old-wi-fi-router-into-an-access-point/
I’ve done this type of thing before. Put the router as a Access point on top of 25’ telephone pole at my show, with homebrew wifi feedhorn antenna I could access it from 4 miles away with standard Wifi card in laptop. My access point was connected to the web, but it could just as easily be an old computer running as a server without the web. I used commercial 6db collinear antenna, but you can homebrew them with soldered together pieces of coax in fiberglass tube or just sealed and hung from stick or tree on the top.
Will try an find one of the old articles that showed exactly where and how to attach the N-connector for the antenna.
Hand held VHF/UHF transceivers can be used to use things like packet radio. The bandpass will not handle high bandwidth data but slower it will.
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