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I am posting this question (and its related question) here because of the unique expertise that Ham Radio Operators have as it relates to antennas. I'm a newish Ham and really appreciate your help with this challenge.

As discussed in the related question, I am interested in building an antenna array that picks up on stellar emissions. I am trading localizability (i.e. the ability to pinpoint the source) for recording as much of the sky in as broad a bandwidth as possible. Practically speaking, that means recording EM emissions within the "Radio Window", which is about 0.5 cm to about 30 m.

The answers in the other question were extremely helpful, and in doing further research, I stumbled upon biconical antennas. A search on this forum only yields a handful of questions that touch on this antenna type in passing. It appears that biconical antennas have a broad bandwidth with considerable overlap to the radio window - 20 MHz to as high as 300 MHz (I need 10 MHz to 60 GHz). Theoretically, a second antenna (log periodic?? loop??) to pickup on the 10 MHz to 20 MHz spectrum.

Biconical Antenna

Here's the question: my HOA prohibits mounting anything that looks like an antenna on the property. I can place an antenna flat on the ground, but that's not going to work with a biconical antenna as far as I can tell. I read in this article that someone mounted a Double Cross antenna in their attic and received decent signals. My house has concrete shingle tile. If I built a biconical antenna and mounted in my attic, would I still receive transmissions in the frequency range I am looking for?

Thanks for all your advice!

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    $\begingroup$ I found this on Arxiv: arxiv.org/pdf/2004.12568.pdf. See Table III. I'm led to believe that a humble concrete tile won't be enough to stop stellar EM transmissions... the attenuation appears to be very small. A wet day might have an impact, however. $\endgroup$ – FontFamily Feb 3 at 16:36
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    $\begingroup$ How will you separate your desired observations from terrestrial noise sources if your antenna has low directivity? $\endgroup$ – Phil Frost - W8II Feb 3 at 16:44
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    $\begingroup$ Ouch. I didn't consider that element, especially given how crowded some of those frequencies are getting. We aren't far enough from civilization to isolate geographically. The issue with the directional antennas I looked at is that they just point to a small section of the universe. What do you suggest? $\endgroup$ – FontFamily Feb 3 at 17:22
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    $\begingroup$ Depends on what you're trying to accomplish, I suppose. What's your use case for recording the RF emissions of the entire sky? $\endgroup$ – Phil Frost - W8II Feb 3 at 17:28
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    $\begingroup$ That doesn't sound feasible. There's too much noise. That would be like trying to listen to one spectator's iPod with a single microphone in the center of a crowded stadium. Except harder. $\endgroup$ – Phil Frost - W8II Feb 3 at 17:49

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