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Questions tagged [antenna]

Questions about the design, selection, building, testing, mounting, or properties of antennas. See also specific tags: [antenna-theory], [antenna-construction], [dipole], etc.

This tag is appropriate for any question relating to an antenna. It should only be used if the question is about antennas, general questions about using or setting up a radio do not belong here, nor do general questions about reception or interference.

Use this tag any time you're asking about a specific antenna, including practical questions (how to build it) and theoretical questions (how it works). This tag is also appropriate for mounting or setting up antennas, testing antennas for SWR or with an antenna analyzer, selecting materials to use for an antenna, or questions about commercial antennas.

Consider also using a more specific tag, such as:

Tags related to specific types of antennas: , , , , , , , , , , ,

Related subjects:

965 questions
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What kind of antenna is that one?

Yesterday I saw the following antenna: I am very puzzled, at first glance it seems a simple dish but: The mesh is really wide (low frequency?). It is pointing to Zenith. I think that most dish antennas rest in zenith position to offer less…
Seitam
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How to Evaluate Antenna Data

I found some data on antennas that had been tested for a specific radio. I'm trying to decipher what this data means and how one would go about gathering it. Are there any good resource for learning how to read and understand this…
Dan
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What kind of antenna has a spiral connected to a reflector like this picture?

The description on the antenna says it is used for satellite communication, but it was taken in 1984. Is this an antenna style that is still in use? What is it called? What kind of gain should be expected? Is this a style used primarily or only for…
Jason Petrilla
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Drones for lifting verticals?

I would like to lift a 5/8 wave wire vertical for 160m, using a drone, over my lovely saltwater swamp. The thing must be powered from the ground, capable of being left aloft for a couple of hours while I work DX, and capable of hovering in position…
VE6MRV
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Why a thousand miles long antenna is not needed to receive LW and MW?

From what I've learnt so far, the longer the wave frequency on which you want to transmit or receive, the longer the antenna needed to do so. However my portable receiver other than SW can also receive LW and MW, and is receiving those using its…
red-o-alf
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How does a Dual Band Handheld Antenna work?

Looking to get a (highly recommended) NAGOYA NA-771 37cm "Dual band (2M/70cm) handheld antenna" for my Baofeng UV-5R. If my math is correct - this is about a half-wavelength antenna for 70cm, but doesn't seem to correlate to anything for 2m. What…
Brad
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How do I identify a genuine Nagoya antenna?

I recently purchased a Nagoya NA-771 that I believe is counterfeit given the overall feel of the antenna. How do I identify a genuine Nagoya antenna vs. a counterfeit?
Amin Shah Gilani
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Is this a broadcasting antenna?

We bought an old house and found an antenna inside the attic of the house. I don't know much about antennas or radio but searching in Google I found a similarly shaped one and it describes it as a broadcasting one. Is that what this antenna is? If…
Wilreyca
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What kind of antenna is this?

This was found among some old ham stuff and is believed to have been used on 2 meters. The vertical elements are 17 1/2" long and the connector on the bottom is a standard SO-239. Antenna (left) and Connector (right) (See test results below…
Lance
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Can antennas have reverse harmonics

I know antennas can have 1/4 wavelength, 1/8th etc. but if you are operating from UHF bands, can the antenna be lets say twice as long?
Skyler 440
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Distance between antenna and radio

I live in a small cottage with an unlevelled terrain. My house was built in the lower part of it (left-side), and in the other half of it there is a hill. On top of the hill there's a fairly good plateau where I would like to have my antennas…
Former User of Mine
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Can PIM occur with one carrier?

the literature talks about PIM occuring with two or more carriers: can it not happen in a single carrier antenna? e.g. creating second harmonic (2*f)?
user5448
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Can my small ham radio antenna interfere with WiFi in my RV park?

We live full time in our RV. We are at an RV park for the winter. They just knocked on my door and asked what kind of antenna I have on top of my RV. I told them it's a small ham radio antenna that I use only for monitoring at this time. I was told…
pris
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Why did the International Telecommunications Union denote CY for Canada?

CGP Grey recently released a video on the history of airport acronyms, e.g., LAX. He briefly said that you may wonder why codes for Canada started with Y and formerly CY, and that it traced its history to the telegram “but that’s a story for another…
Ethan Miller
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Understanding Impedance (R+jx)

In a typical antenna (lets say dipole for this discussion), the pattern below is observed in the impedance (R+jx) graph: I'm trying to wrap my head around this graph. Why does the resistance spike, and what is the significance of the interval it…
t252
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