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No no, not a vertical. Horizontal orientation models only. There wasn't a name for this antenna in a 1958 article by?M. J. Heavyside, Ph.D (G2QM) he published theory and a report of his work.

So, others called it a variety of names. I wrote to UK hams abiut two years ago who sourced the article for me from their archives.??

N2VIP Which ARRL era publication would have published this??

So far the most apt name I have used in my modeling is non-inductive end-loaded antenna (NEDA)? comprising radiating and non-radatinv regions. Selecting 80m to 10m coverage I got 1ft H X 1ft w X 12ft L.?

L is horizontal dimension, total length.?

We made a third version of this system with a poly fabric embedded with antenna elements ... total dimensions 12ft L x 2.5ft W x 1 inch. It did work, better than others, but the wind blew the damn antenna post tripod over as we had created a sail that twists and turns with gusts. Well we have a lot of engineering to do on that one.?

Sorry I don't have any nice pictures to distribute as we are just experimenting with materials and all of our tests are cheaply made up of home depot products. The measurements are somewhat different between prototypes as we discover the cost of the parts we have to fabricate and make durable for long term outside use. It's should be a mature design for showing in a few months.?

73 de X

On Sun, Feb 19, 2023, 22:51 Ken N2VIP <ken@...> wrote:

Apparently it's a type of vertical (1' x 1' x 12').

Is there a reason to think this design is not included in the ARRL publications of the era

Ken, N2VIP

On Feb 19, 2023, at 21:45, Joseph Wonoski via <N1KHB=[email protected]> wrote:

?What general type of antenna is it?

Joe n1khb

On Sun, Feb 19, 2023 at 9:39 PM, Samudra

<samudra.haque@...> wrote:

Hi,

?

FT-817 QRP users, I am one of the developers of ?a modern incarnation of a very old design HF antenna (post WW2 apparently from the documentation I have) that was rediscovered/tested by other hams in the 70s-80s, and 90s. But then it was left alone AFAIK. We will soon have it on the air with my FT-817ND radio that I repaired a year plus ago, with the help of this forum members (Thank you). Our test cases will be SSB voice, and FT8 or other digital modes over a weekend coming up. Looking for regional contacts to try scheduled tests.

?

In the DC/MD/VA region of US, I worked with a few business colleagues/ham radio operators to design/test/develop and fabricate working prototypes. Three versions are in testing now. What I am hoping is someone interested in antenna testing/fabrication will be able to indicate if what we are getting with an MFJ antenna analyzer and a MFJ antenna tuner (all we have in the field, but I have more equipment in my RF test lab – not at the placed where the antenna is being fielded) is good or not:

?

3.750 MHz ~ 1.0-1.1 SWR

7.010 MHz ~ 1.1-1.2 SWR

14.200~250 MHz – 1.3 SWR

…

28 MHz – 1.2x SWR

?

These were the first trials, with the fully assembled kit about 6 feet a.g.l. Total dimension is approximately: 1ft x 1ft x 12ft. It’s a geometrically complex antenna design, that hurts most antenna analyzing software. We haven’t got the lifting system in place to erect it safely to about 20 feet a.g.l. so this is the best we can do for now.

?

Any comments on the statistics I am presenting welcome. I was not expecting so low SWR and we haven’t tried with a live transceiver yet. But there are very distinct notches and our dimensions of the radiation region was even bang on from antenna modeling theory with some margin. Feeder was a 50 ohm coax to manual antenna tuner unit of about 25ft length.

?

We are wondering if it would be interesting to any with small space for antennas? What are your thoughts and requirements on packaging/support/reliability ? It’s becoming a challenge to source all parts at low cost and yet have good manufacturability and repeatability with the complex measurements mechanical and electrical per the design.

?

73 de N3RDX

Washington, DC