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1. ｍｎｇｒｉｆ :kentucky: (mngrif@qoto.org)'s status on Thursday, 29-Aug-2019 21:14:34 UTC ｍｎｇｒｉｆ :kentucky:

   http://udel.edu/~mm/ham/randomWire/ apparently random wires should not be so random.

   i was thinking of running one through the requisite 9:1 as a SDR's receiving antenna. how bad of an idea is this compared to other receive-only HF antennas?

   • 🎓 Dr. Freemo :jpf: 🇳🇱 repeated this.
   • 🎓 Dr. Freemo :jpf: 🇳🇱 (freemo@qoto.org)'s status on Thursday, 29-Aug-2019 21:17:09 UTC 🎓 Dr. Freemo :jpf: 🇳🇱

     @mngrif I mean random wire will generally be the worst and leadt predictable on receive. but its totally doable. Plus if it is long enough that it is several orders longer thant he Wavelength you will have an interesting effect of a sort of randomized directionality. Some channels will be almost undetectable others will come in exceptionally clear. At least compared to the same antenna of proper length.

   • 🎓 Dr. Freemo :jpf: 🇳🇱 (freemo@qoto.org)'s status on Thursday, 29-Aug-2019 21:23:21 UTC 🎓 Dr. Freemo :jpf: 🇳🇱

     @mngrif Impedance matching isnt itself an indication of any sort of issue. The reason it is, indirectly, is it means your antenna's impedance is likely mismatches with the impedance of free-space. Which means it likely wont radiate all that much. This is mostly just due to the fact that near the ground the impedance of the space is closer to 50 ohms even though if you were out in space it would be closer to 400 ohms.

   • 🎓 Dr. Freemo :jpf: 🇳🇱 (freemo@qoto.org)'s status on Thursday, 29-Aug-2019 21:24:32 UTC 🎓 Dr. Freemo :jpf: 🇳🇱

     @mngrif Magloops? Those follow some really different rules. Generally they dont tune by balun or coils but rather by capacitance as they tend to be tuned int he other direction of baseline naturally

     Federation Bot repeated this.
   • 🎓 Dr. Freemo :jpf: 🇳🇱 (freemo@qoto.org)'s status on Thursday, 29-Aug-2019 21:29:39 UTC 🎓 Dr. Freemo :jpf: 🇳🇱

     @mngrif Ahhh yea those are cool, havent gotten to use one though.

   • 🎓 Dr. Freemo :jpf: 🇳🇱 (freemo@qoto.org)'s status on Thursday, 29-Aug-2019 21:30:50 UTC 🎓 Dr. Freemo :jpf: 🇳🇱

     @mngrif You can get almost any antenna to work if you have enough space and dont care to much about directionality :) Though loops in general are pretty well performing antennas. I mean anything with as few traps and coils as possible is going to be good if you have the space.

   • 🎓 Dr. Freemo :jpf: 🇳🇱 (freemo@qoto.org)'s status on Thursday, 29-Aug-2019 21:40:03 UTC 🎓 Dr. Freemo :jpf: 🇳🇱

     @mngrif It would be fun. MagLoops are my favorite for receive. Thats really where they shine. Havent really tested the setup your going with though.