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I always thought it would be cool to make a little portable kit to fly an antenna/relay in case of emergency. The practical solution would probably be a parafo
by jcims 7y ago
I always thought it would be cool to make a little portable kit to fly an antenna/relay in case of emergency. The practical solution would probably be a parafoil, but a chemical hydrogen generator and balloon would be way more fun.
- superkuh 7y agoSome way to get height above terrain is required. One of the more game changing ways I've heard about is using specially shaped TEM mode launchers with thin single wires to transmit RF power up to a hovering quadcopter to be rectified. Glenn Elmore has published some articles about these surface wave transmission lines in the amateur radio magazine QEX (mirrors at: http://www.sonic.net/~n6gn/ http://www.sonic.net/~n6gn/) and documented some 50w power tests on his youtube channel, https://www.youtube.com/user/n6gnSWTL https://www.youtube.com/user/n6gnSWTL I implemented a pair of these launchers designed for my 900 MHz "wifi" setup using a ubiquiti 900 MHz tranceiver running broadband hamnet firmware. It seemed to carry the signal to the antenna as well as a similar length of RG-6 coax. http://erewhon.superkuh.com/swtl_launcher_complete.jpg http://erewhon.superkuh.com/swtl_launcher_complete.jpg It was a little fragile and the connection to the SMA connector broke on one. Some day I need to resolder it and put one end up in a tree. Glenn's 2.5d metallized paper designs look much easier to build and more robust.