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Old December 30th 19, 03:53 PM posted to rec.aviation.soaring
Eric Greenwell[_4_]
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Default Locating Transponder Antenna on top of the fuselage instead ofunder it.

jfitch wrote on 12/29/2019 10:16 PM:
And uh.... not relevant... the pilot is inside his carbon fiber partial faraday cage cockpit, and (agreeing with Eric) the pattern from the 1/4 wave antenna with groundplane shields the pilot from the antenna.

Over a beer some time: details of teaching assistants punking male students in their undergrad physics lab classes into wearing aluminium foil "mini skirts" during a_very_ low power microwave experiment. Oh so well done.

You'd need to show me the data on that. A minimally conductive carbon fuselage with some huge holes in it, a very imperfect 1/4 wave vs. twice the distance. We're talking r^3 here. I'm not actually sure what measurements might show, and I wouldn't bet my glider on one answer over the other.


Not r^3, but only r^2 for antenna field strength reduction. It's an area thing,
not a volume thing.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1