Questions tagged [antenna-construction]

Materials and methods for building antennas, and design of supporting (non-conductive) structures. For design of antennas themselves, use [antenna-theory] instead.

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35 views

Lightning protection for a vent stack antenna

I've seen ham radio antennas that slide over a vent stack. The usually way to connect them to the transceiver is to lay the feedline across the roof. However, the manufacturer provides instructions ...
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0answers
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BS or Not: Hybrid-Yagi : (horizontal polarization): Angled Twin Director Element Booms Are Effective for DX Antenna [closed]

Using your best knowledge about antennas and their construction and geometry, what would make the antenna below's design choices a best or worst design choice to achieve long distance (up to 140km) ...
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2answers
72 views

Antenna Basics - Open/Short Circuit & Half-Duplex/Full-Duplex

I am beginner in the Antenna theory and I have a few basic questions. Please help me to clarify my understandings related to the basics which I have read. And this question has 3 basic questions. ...
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5answers
260 views

Significance of 1/4 wavelength with respect to antennas

I am a fresher in the radio design field. My question is, 'What is so significant about 1/4 wavelength with respect to antennas.' From the information I have gathered from various sources, it is my ...
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3answers
117 views

Need antenna for mobile mag-mount LPFM broadcast 88.3 MHz

I am doing some temporary FM broadcasting for car events such as COVID-safe car parades and drive-in movies. The terrain is horrible, urban areas with lots of buildings. The cars snake around a city, ...
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6answers
2k views

Can you use a satellite dish for a ham radio antenna?

Can I use a satellite dish as a ham radio antenna? I was thinking that because there are two unused, working satellite dishes that have all appropriate wires attached conveniently to the roof of my ...
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2answers
76 views

Yagi: split or solid driven element?

Short question: What are the advantages and disadvantages of using gamma (solid element) or beta (split element) matching a yagi? Long question: A while ago I built a coil loaded yagi for the 20M ...
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2answers
138 views

Magnetic loop antenna : loops vs selectivity

I've built 2-turn magnetic loop RX antenna using 5 meters of 6.5mm copper tube. I was able to tune it with a variable air-spaced capacitor in the range of 1.8-10Mhz, but I noticed that as tuning ...
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1answer
96 views

Commercial Loopstick Antenna Manufacturers

Not sure this is the right forum for this but I thought I'd give it a shot. I am an electrical engineer working on a product that needs a loopstick antenna. I had thought that AM radios were so ...
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5answers
110 views

2.45GHz: constructing a horn of *thin* steel, what are good ways to join the edges (at least one joint along corner?)

TL/DR: How does someone make a good horn antenna system without using expensively made parts? Welding thin steel for this is not something even pro welders can do (it's a specialty app.) What are DIY ...
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3answers
116 views

Can I build a guanella balun using single strand wire instead of coax?

I am trying to homebrew a cobweb antenna and need some help understanding the guanella balun used as described here: http://www.karinya.net/g3txq/cobweb/ This author used RG316 coax around the ...
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3answers
249 views

High Altitude Balloon Antenna Design

I'm designing a weather balloon with a club at college. We want to build the antenna from scratch to learn more about antennas but are at a loss as to which antenna design would actually work for high ...
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2answers
89 views

Does RF go through thin corrosion better than DC?

I might have a bit of a problem with my groundplane, but I am unsure. I am using a ground screen instead of radials. The problem is the ground screen is made of galvanized metal, but I can see that a ...
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4answers
110 views

Which 10 m antenna will give the most rejection in one direction for received signals which are vertically polarized?

I want to null out a particular direction so that i can't receive some vertically polarized interference on 10 m coming from that direction. Which 10 m antenna will give the most rejection in one ...
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1answer
223 views

Will painting a 4 element 10 m yagi using conductive paint onto the side of a building work?

Will painting a 4 element yagi using conductive paint onto the side of a building work?
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1answer
61 views

Is there a suitable alternative to using a metal pole to mount a vertical yagi apart from wood and fiber glass?

Does anyone know if a non-metallic pole approx. 4 m long is available that i can use to mount a vertical 10 m 4 element yagi ? that is not wood, PVC or fiber glass as these are either too heavy or not ...
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2answers
65 views

Will ferrite rings around a metal pole hide it in an RF sense from my vertical 10 m Yagi?

If i mount my vertical 10 m 4 element yagi directly on a metal pole so that the pole is between the elements and so messes up the radiation pattern and input impedance, if i put lots of type 43 ...
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1answer
207 views

When I am told that a dipole must have a determined length, does that include the space between both elements?

I am trying to build an antenna for receiving NOAA satellites and I need to build two 137,5MHz dipoles. When I enter the frequency and width of the wires in a calculator, I obtain that $λ/2=1.09\,\...
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3answers
685 views

Can I build a Yagi antenna for my Baofeng UV-5R?

I would like to build a Yagi antenna for my Baofeng UV-5R, but I'm a total newbie when it comes to amateur radios. The antenna will be for UHF and shouldn't be too long (like 1.5 meters max). So my ...
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1answer
92 views

UHF cubical quad VNA analysis interpretation

I've designed a two element UHF cubical quad. It was designed to resonate at 385 Mhz. I used 0.1mm thick and 1cm wide copper tape instead of wire to lower the antenna Q. I used PVC electrical conduit ...
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0answers
76 views

How do I Construct a Simple FM Antenna?

I recently bought a cheap stereo amplifier with built in FM receiver from Amazon at the first link below. Testing it out today I found the FM reception to be sub-par. All of my local stations that I ...
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1answer
77 views

Need help understanding the gain on antenna pattern plots

My understanding is that the value of the axis (like -10 / 0 dB) refers to the maximum antenna gain (e.g. 12dbi). So, if a ...
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1answer
73 views

Somewhat-directional (cardioid?) antenna for receiving ADS-B?

I recently set up my own RTL-SDR-based ADS-B receiver. I live in a Manhattan high-rise with an eastern view, so I do not get any signals from behind the building (almost: I get the occasional ...
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2answers
183 views

House wiring as an antenna on HF and 2 meters?

The apartment I live in is a 1970s type without access to the outdoors. It does have a balcony. A 2m transceiver is the only radio which will enable me to reach the ham world. Would be possible to ...
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1answer
208 views

How do I design a dual band LPDA antenna?

Im not sure if this is the best place to ask a question like this but its the best place i could find. My goal is to build a dual band antenna similar to this one. That covers ...
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0answers
48 views

What's the issue with stainless steel antenna elements? [duplicate]

New ham, here...getting motivated to build some antennas to experiment with and so far my research has shown that stainless steel is not a desirable metal for creating antenna elements - which is a ...
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0answers
35 views

Unsure how to assemble Shakespeare SSB antenna; not working [closed]

Have 23 foot Shakespeare SSB antenna. Can not connect through the side feed termination band? Antenna not working? What is the band supposed to look like? Is the termination band supposed to be ...
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3answers
260 views

2m 5-element yagi with staggered driven elements

I have seen sketches of 3-element 2m yagi antennas in which the driven dipole elements are staggered i.e., one element is positioned slightly in front of the other along the length of the (plastic) ...
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1answer
88 views

Radio antenna for my FM receiver / Android FM

I want to make a radio antenna at home which will be able to receive all FM frequencies for my FM radio or Android FM. How do I make it? Frequency it can catch : 88 - 108 MHz Thanks.
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2answers
93 views

Dielectric Constant of Insulation/RF Permeability

I recently purchased a 500-foot roll of military surplus 14 AWG stranded copper wire at a hamfest for next to nothing . It is Prestolite M13486/1-6 (spec sheet). It has very thick chlorinated ...
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1answer
52 views

Are stainless steel studs acceptable as a feedpoint connector for an aluminum loop antenna?

Similar to Will stainless steel bolts work with my copper antenna? however my concern here is with electrical properties. With copper antennas I never gave it much thought... just solder the wire. I ...
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2answers
84 views

Matching a 188 ohm antenna to an unbalanced input that expects a 50 ohm antenna

I am new to RF field and trying to use an Archimedean Spiral Antenna design from this paper to capture 915MHz RF for the P2110B power harvester chip. The estimated antenna impedance is 188 Ohm (see ...
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2answers
79 views

Will close-loop metal hangers affect antenna radiation?

I'm working on a kite-supported antenna for an 80m QRP rig -- to be flown at beaches, on mountaintops, and possibly other places where I want to work HF but don't want to lug poles or give up ...
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1answer
1k views

3 Band (80-40-20 Meter) Fan Dipole Tuning Question

I built a fan dipole according to the basic instructions in the SRI publication describing the theory and basic design. My questions is about next steps in tuning for the various bands. I am ...
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2answers
94 views

Low mass, low frequency transmission line

I'm interested in a low frequency (10 MHz - 100 MHz) radio receiver array, made up of crossed dipole antennas. I'm working on a design project mainly focused on the mechanical engineering side of ...
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5answers
773 views

Loop antenna layout and radiation?

I've got, for the near term, limited resources to put up an HF antenna at my home. One of the options I can manage without excessive cost is a loop, which would enclose the house. I need to transmit ...
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4answers
1k views

Antenna options for a 10x20m property with a large metal roof?

I live in a house that sits in the middle of the city, in a lot 10x20m in size. The first 6x10m are covered by a metal roof with a rather low angle (IIRC only 50cm difference between the highest and ...
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3answers
706 views

RigExpert AA-35 - Interpreting The Information

I have a new RigExpert AA-35 antenna analyzer. 1st one I have had & 1st time trying to use an analyzer on an antenna. My questions are very basic and general, but I am having difficulty in ...
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1answer
181 views

How do I use multiple antennas with two or more radios?

I'm building multiple antennas tuned to different amateur bands and would like them connected to my SDR for remote listening and analysis, and a handheld radio for transmission, which I may upgrade or ...
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3answers
194 views

How can a vertical Yagi for 10 m be mounted on on a vertical metal mast and be made to work properly? [duplicate]

From a reply to a previous post I've been told that a horizontal tube half a wavelength long mounted right at the junction between the boom on a vertically mounted yagi and a vertical metal pole will ...
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2answers
77 views

Proper magnetic mount placement on roof

I have a Nissan Versa 2012 (hatchback). It comes with one of those default antennas at the back/center of the roof, for listening to AM/FM radio stations. I have a dual band mag-mount (TRAM 1185), ...
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2answers
393 views

How does an E-Z-O Antenna work and why does it appear in Wikipedia's article on quad antennas?

How are the conductors/radiators in the E-Z-O Antenna configured, and why is it described in Wikipedia's article Quad antenna? I see three circles and a spider web of wires inside each, but from an ...
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3answers
920 views

What happens to a vertical Yagi when you mount it on a vertical metal pole?

How much difference does a metal pole make when it's sitting in the middle of all the lower elements of my beautiful new highly optimized to the max YO.EXE 10 m yagi ? I get it that the closeness of ...
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2answers
195 views

Shortwave antenna wire — do I care about “corona discharge”?

Just researching an outdoor long run shortwave antenna. I found some cheap wire online but it said it is resistant to corona discharge: Will satisfy a wide number of applications related to medical,...
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4answers
284 views

Why are there differences in antennas that depend on electrical component and magnetic component of a radio wave?

I understand the idea that when we are targeting the electrical component of the radio waves we need to have some form of a linear conductor that receives the electrical component, this creates a ...
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3answers
618 views

antenna in the rain

What kind of changes can be expected in the behavior (resonance, SWR, etc.) of a mobile vertical HF antenna between dry conditions and wet rainy weather? (assume a coax feed-line and low SWR in dry ...
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1answer
107 views

asymmetric shortened dipole

It seems a resonant dipole can be shortened by either loading coils near the center feed point or capacitive "hats" at the ends (and still be resonant). Say I run out of linear physical distance for ...
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2answers
1k views

Simple Longwire/Dipole Antenna design

In a couple of days I am going to a mountain cabin and I were thinking about making myself a semi broadband antenna for LF/HF (300KHz - 20MHz or so) for receiving only. I was thinking about creating ...
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3answers
290 views

Can I use a helical ground plane radial in the same way that a loading coil works?

I'm working out the science behind mounting an antenna on a vehicle, and I came across the concept of ground planes. This answer says that longer is better but don't worry about it too much, but this ...
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1answer
195 views

Antenna for receiving 868MHz rocket telemetry: QFH(QHA), Helical, or?

I'm building a radio communication system for an amateur rocket project. We've decided to use LoRa 868MHz system. My question is, which antenna for the ground station will be the best choice? We're ...