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Questions tagged [antenna-theory]

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Designing antennas, selecting antennas for specific applications, properties of a given antenna design.

14 questions with no upvoted or accepted answers
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4 votes
0 answers
116 views

There are research and examples of "fractal antennas" where the radiator is in a "fractal-like" shape, mostly to save space. Those antennas often come with a penalty in gain (...
Ryuji AB1WX's user avatar
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3 votes
0 answers
569 views

The conventional turnstile antenna uses a 1/4wl phasing line between the crossed elements, to get the required phase shift. 4nec2 includes an example file, though, of a circularly-polarized Yagi using ...
1200bps's user avatar
  • 31
3 votes
0 answers
221 views

Is this author correct about using a λ/2 of wire for a coil to get the proper delay on a λ/2 collinear antenna? Improving the Super-J August 5, 2012 by John S. Huggins I agree with him that there has ...
Louis Seaman's user avatar
  • 1,217
3 votes
0 answers
350 views

I had a 100cm prime focus dish laying around and I thought of making a circularly polarized feed for it, since it seemed pretty straightforward from what I've been reading. Helical feeds are supposed ...
hjf's user avatar
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2 votes
0 answers
72 views

Assuming a rhombic antenna is: terminated for directionality electrically isolated at its mount point mounted to a metal mast partway up vs top of mast horizontally oriented (elements parallel to ...
Joshua Nozzi W4JLN's user avatar
  • 386
2 votes
0 answers
146 views

let's consider a printed dipole on a substrate with a GND plane: I've seen many times an equivalent model which uses transmission lines like this (reference): This model is useful to understand the ...
Kinka-Byo's user avatar
  • 289
1 vote
0 answers
122 views

Conversion from nec2 geometry to x3d or some other format to read nec2 geometry files into (ultimately) OpenEMS would I think be good. I found a reference in a document ...
Pete's user avatar
  • 11
1 vote
1 answer
415 views

I have used my small loop antenna (which has a main loop and a coupling loop that can be tuned using a variable capacitor) with an AM radio receiver to receive MW broadcasts. However, the small loop ...
user avatar
1 vote
0 answers
157 views

I am trying to get my N1CC and would like to get on 160 meters for pota. I can get a vertical that is 39 feet tall set up at the park. I know it will be narrow banded and take a large loading coil, ...
sam's user avatar
  • 11
1 vote
1 answer
267 views

I've seen several antenna types out there, but I can't know for sure which model is the best for external/outdoor LTE (4G) use. I have to say that I don't understand anything about LTE (4G) antennas......
Eduardo Lúcio's user avatar
  • 125
1 vote
0 answers
83 views

I am attempting to design an antenna similar to a TTFD, double zepp or array of end fed wires, with a sinusoidal, with the period of the wavelength, spacing that causes additive waves on the target ...
KX4UQ's user avatar
  • 349
1 vote
0 answers
299 views

I wonder whether the source code of VE6YP (Tony Field) coaxtrap design program (link 1, link 2) was ever published or described. As a Mac user I'm having little difficulties using this software and I ...
Aleksander Alekseev - R2AUK's user avatar
  • 4,347
0 votes
0 answers
86 views

everyone! In ADS Keysight it is possible to create an item model - the so-called User-Defined Model. This is C++ code that describes the Y-matrix of the component. Is there the same possibility in AWR ...
Евгений Федоров's user avatar
  • 3
0 votes
0 answers
564 views

Trying to lengthen my 10mtr. end fed to 39 metres in length. To do this I need the first leg (10mtr.) to run at a lower height approx (5mtr)turning back on a dog leg, and the final 29 meters then ...
Chris.G0MRR's user avatar
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