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HF in an HOA

Posted: Wed Jul 03, 2024 7:20 am
by Andrew (grayhat)
A paper describing a simple, cheap antenna which is also stealth and will allow to work all HF

https://www.qsotoday.com/uploads/2/4/5/ ... t_expo.pdf

sure, it isn't a "beam" it's a compromise antenna, but then if one hasn't the luxury of having plenty of space to setup an antenna and is also penalized by HOA, the above may be a good compromise allowing to "put out the nose" on the HF bands, for further informations see

http://hflink.com/antenna/#BBTDROOF

a suggestion for the ones willing to give it a try, pick some cheap, low power non inductive resistors on "AliExpress", some 1W...5W ones will do, pick various values then connect them in series/parallel until you'll find the best match with your antenna (the total perimeter is what you have so the termination needs to be adjusted to that), once found the desired value, pick (say) 5 resistors which, once connected in parallel will give you about that value and with the desired dissipation and use them for the definitive termination, that will allow you to obtain low SWR on all bands w/o the need for any kind of tuner

Re: HF in an HOA

Posted: Tue Jul 09, 2024 2:53 pm
by KL7MJ
A poor antenna is better than no antenna (although my logbook might disagree).

The demise of visible external antennas has probably impacted the recruiting of new hams. In my case, I wanted to get a ham license when I was a boy, but I didn't know any hams in my area. My family moved to a new town when I was starting high school, and there were two hams in the neighborhood with 120 foot towers. All I had to do was knock on a door and say, "I want to learn how to be a ham" and the rest was history.

Re: HF in an HOA

Posted: Wed Jul 10, 2024 7:14 am
by Andrew (grayhat)
KL7MJ wrote: Tue Jul 09, 2024 2:53 pm A poor antenna is better than no antenna (although my logbook might disagree).
Well, if the choice is between some "arranged" antenna and no antenna at all, I think most people will go for the first; I'm not saying that the BBTD installed in an attic or around a roof is a "beam", but let me try an example, let's say a guy loves going portable for POTA/SOTA but then, from time to time he likes also getting on air from home, pity he's plagued from HOA and/or has little room to setup an antenna, at this point the BBTD would allow him to, at least, put "the nose out" on many bands
KL7MJ wrote: Tue Jul 09, 2024 2:53 pm The demise of visible external antennas has probably impacted the recruiting of new hams. In my case, I wanted to get a ham license when I was a boy, but I didn't know any hams in my area. My family moved to a new town when I was starting high school, and there were two hams in the neighborhood with 120 foot towers. All I had to do was knock on a door and say, "I want to learn how to be a ham" and the rest was history.
Well, if one can install a tower and/or an antenna farm, no problems, but for the ones which can't and/or are plagued by HOA restrictions, the BBTD may be a way to get on the air

Re: HF in an HOA

Posted: Wed Jul 10, 2024 5:15 pm
by KL7MJ
Andrew (grayhat) wrote: Wed Jul 10, 2024 7:14 am at this point the BBTD would allow him to, at least, put "the nose out" on many bands
This sounds like a good design. I used a fan dipole in the attic when I lived in Germany, which did very well - the roof was ceramic tile over wooden beams, so it wasn't too noisy. I like the idea that this antenna has some gain, although I'm sure that varies greatly depending on attic space available.

Andrew (grayhat) wrote: Wed Jul 10, 2024 7:14 am Well, if one can install a tower and/or an antenna farm, no problems, but for the ones which can't and/or are plagued by HOA restrictions, the BBTD may be a way to get on the air
Sorry, this was more of a lament that amateurs are not as visible as we once were, myself included. My HOA only allows antennas on the roof of the house, and I'm not thrilled about sticking a giant lightning rod up there, so I use an EFRW in a tree that I take down when the weather looks bad.

Re: HF in an HOA

Posted: Thu Jul 11, 2024 6:56 am
by Andrew (grayhat)
KL7MJ wrote: Wed Jul 10, 2024 5:15 pm This sounds like a good design. I used a fan dipole in the attic when I lived in Germany, which did very well - the roof was ceramic tile over wooden beams, so it wasn't too noisy. I like the idea that this antenna has some gain, although I'm sure that varies greatly depending on attic space available.
Gain isn't stellar and, as you correctly wrote, it mainly depends from the overall length of the loop wire, the advantage of the terminated loop over the fan dipole (in an attic) is that once the termination resistor value is adjusted, you won't need an ATU and the loop, being an aperiodic (non resonant) antenna will work on "all bands" so allowing a bit of frequency agility; again, can't compare it to a doublet in free air or a beam at the top of a tower, but that isn't the purpose, as I wrote the idea is that it will allow people with limited space or with "HOA issues" to install an "invisible antenna" and play Ham Radio :D
KL7MJ wrote: Wed Jul 10, 2024 5:15 pm Sorry, this was more of a lament that amateurs are not as visible as we once were, myself included. My HOA only allows antennas on the roof of the house, and I'm not thrilled about sticking a giant lightning rod up there, so I use an EFRW in a tree that I take down when the weather looks bad.
I misinterpreted it, forgive me ! As for your HOA, you may either try the BBTD or, either, have a look at the "Fat Max" antenna

https://web.archive.org/web/20230722120 ... ntenna.pdf

just place a "bird feeder" at the top of the pipe and it won't look like an antenna, yet it will allow to cover several bands, again, it's another way to "hide" the antenna, so don't expect stellar performances, yet ...