Project TouCans Antenna Feed Redesign

Halibut Electronics is working on a new satellite antenna kit!

This is kinda cool for two reasons, first because we've recently started attending the high altitude balloon meetups at Noisebridge. Satellite antennas came up during one of the meetings.

More tactically importanly though, the EggNogs docs inspired what be a better tuna can feedtrough for Projct TouCan's antenna! For notes, here's my original EggNogs documentation review reply:

The documentation looks great so far! I've made it to page 17/22. One thing:

For those of us with partners heavily into fountain pens, those of us who like to print out manuals on JIS B5 paper and then store them in Kokuyo Campus binders, page numbers in the table of contents would be very cool. (I know, I know, such a niche group :) )

Mostly though, I wanted to thank you for jogging my memory into a, (I hope), better solution for Project TouCans antenna ports. At present, they're inverted bananna plug posts. Banana plug screw terminals are tiny, and therefore somewhat problematic in outdoor environments. Here's an idea of how tiny

Suspending a two pound rig 6 meters up, eventually the screw threads begin to strip. We stuck with banana plugs though because the insulator around the conductor makes them perfect for mounting in a tuna fish can. Yes, I've read about how Yagis and dipoles are balanced and therefore have 0 volts across the antenna center, so theoretically you don't need insulators, but TouCans frequently hangs at angles to the ground and/or very close to the ground, so, insulators.

Anyhow! The last figure on page 17, the one with the cool weather-proof washer, reminded me that gromets exist! With the correct sized gromet, we can put any size bolt pointing upward as an antenna connector.

And, even better still, we can source them from our local hardware store at the bottom of the hill!

Thanks Mark!
72 de KD0FNR Hamilton

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