Amateur Radio Stack Exchange
Amateur Radio Stack Exchange

Questions tagged [end-fed-antenna]

31 questions
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votes
7 answers

What is the impedance of an end-fed half-wave antenna?

It is my understanding that the feed-point impedance ($Z_a$) of an end-fed half-wave antenna is dependent on at least the following factors: $L_a$: The length of the radiating element of the antenna. $D_a$: The diameter of the radiating element of…
Robert Quattlebaum
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Do end-fed dipole antennas need choke baluns?

I have a couple of end-fed wire antennas I bought that came with matching baluns. One has a 9:1 unun, and I'm not sure about the other one. In addition to those, should I also put a choke balun on the coax before the matching one?
Pablo Fernandez
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End-fed wire antenna lengths

I want to use an end-fed wire antenna, but what would be the best length of wire for the 20m and 40m bands? Is there a way to work this out? This is assuming a tuner will be used.
Phil_12d3
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6
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3 answers

Does an End-Fed Antenna need to be straight?

Typical yard and wondering if I can go out a window, to a tree, turn to another tree, turn to another tree simply trying to achieve the length required for 80m band? One video stated it doesn't need to be straight, but need to verify.
Mot
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6 answers

Does a 1/2 wavelength end-fed antenna need a good RF ground?

I was searching for DIY end-fed antenna. Some of the articles I found say that for a 1/2 wavelength end-fed I need a "small to no counterpoise" (with a lambda*0.05 m counterpoise), but some other articles say that I need "a good RF ground in close…
Hose Dias
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2 answers

Dipole versus ungrounded end fed for HF RX

I've built a 2 meter ground plane antenna that works pretty well for RX and has a decent SWR on 2 meters with my Alinco. However, I'm experimenting with SDR quite a bit and would really like to build something for weak signals, especially CW and…
David Hoelzer
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Do these look like amateur radio antennas?

I am planning to move into a new apartment, and of course would like to install a HF antenna there, on the roof if possible. Today I noticed a small Yagi antenna on the roof of the building , more than likely for VHF, but more interesting, seems to…
Engineer999
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3 answers

Why a capacitor is needed in Fuchs antenna?

I tried to understand the physics of Fuchs antenna and there is one thing that I don't quite understand. This is probably a very silly question, but I spent a lot of time looking for an answer (books, online) and didn't manage to find it. Modern…
Aleksander Alekseev - R2AUK
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5
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6 answers

EFHW works only on one band - what am I missing?

I tried to build a multiband EFHW antenna as described in articles by PA3HHO, PD7MMA, G0KYA and many others. I decided to start with a short 40/20/(15?)/10 meters version without any loading coils. Surprisingly, no matter what I tried I didn't…
Aleksander Alekseev - R2AUK
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Suggestions for HF antenna for occasional use on my sailboat

I have had a license since I was a kid, but have not touched anything ham radio related in years. I have been thinking about diving back in and combining it with my sailing. I'm looking for thoughts on an HF antenna that I can easily deploy when…
Jim Archer
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How can an HT antenna be half wave?

There's a model of HT antenna for the GMRS band by Nagoya (NA-771G) that's specified as a half wave. How can that be? An end fed half wave antenna needs a 49:1 impedance transformer to match with the transmitter? Is it more like a 5/8 or 3/4 wave…
user3191449
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Do I need an 9:1 UNUN for a half-wave end fed?

I was using a 10-ish meter wire as my HF rx antenna. That's all I can install in my QTH. However I realised that my ~10 m wire can be turned into an end fed dipole for 20 meter band. But there is a question: If I install my tuner close to antenna…
Hose Dias
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Is there a name for this specific variation of L-match tuner (somewhere between L-match and Π-match) and what would be its advantages over L-match?

So I've been looking at the internals of the Icom AT-141 end-fed antenna tuner which I have, and I've noticed that it has some sort of pre-tuning LC stage before its traditional L-tuner network. simulate this circuit – Schematic created using…
AndrejaKo
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What is the optimum length for a random longwire on 10m?

I have all the space in the world and wish to errect a single random longwire to use on the 10 meter band only. I understand that once such a wire is very long, losses associated with the wire itself (a wire of suitable gauge) mean that after a…
Francis Archibald
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Should I use the same grounding rod to ground my radio and my random wire antenna?

I have an end fed random wire antenna about 50 feet from my shack into an antenna tuner. I do not have the option to install a ground rod at the house entrance but I do at the antenna feed point. The antenna tuner requires a very good ground so I…
Zach
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