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.
1,065 questions
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Is lightning protection necessary for a mobile setup?
I am very new to the art of amateur radio, and just got myself an antenna. I don't intend to use it in a permanent location (for example fixed to my house), rather I plan to be using it at parks and ...
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DIY 40m Antenna tuning: RLC and SWR
I keep hearing the recommendation to make your SWR as low as possible and that would imply good tuning.
I'm a new HAM and made a centre-fed half wave fan, 40m, 20, 15m. It works, and pretty well.
I ...
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What causes this "Wedge" in weather Doppler radar imagery?
This is not strictly amateur-related, but the perusing I've done on Meta, and by my reading of https://ham.stackexchange.com/help/on-topic, indicates that this is within scope.
I was looking at the ...
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Alpha Delta DX-B Antenna Installation
I've hung it from the eave of the house (~8') to a tree with the high end at ~20'. Drilled a hole in the aluminum plate for counterpoise stud and connected a 40' counterpoise. Counterpoise is at ~8' ...
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What was this HF six-element Yagi used for? Or: what's it make & model?
When we purchased our house, it came with a Yagi antenna from 30+ years ago, but I can't tell what it is. Until recently, it was too far off the ground to get a good look: A windstorm blew it down two ...
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antenna simulation with OpenEMS designs in FreeCAD and x3d transfer
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 ...
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Measuring Power Transfered to Adjacent Antenna
How can I measure how much power is output from a receiving antenna when another, physically adjacent antenna is transmitting?
I have a VHF/UHF collinear vertical antenna connected to a transceiver ...
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Ever use a SLINKY as an antenna? What frequency is it resonant at?
I read about using a SLINKY out in the field for an antenna. Sounds easy, doesn't it? Well, how does one go about identifying the length needed for the band of interest?
Assume that the slinky has a ...
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Chokes for Multiband Quarter Wave Vertical
I have a Quarter Wave vertical with multiple elements similar to the DX Commander antenna. It's mounted on a metal roof which is acting as my ground plane. I have a run of about 15m of cable back to ...
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How can I estimate the approximate received radio power or signal strength based on limited data?
I am working on a paper that requires to measure a sort of access/exposure of each municipality to the opening of a new radio station in a West African country. I only have the following information ...
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Monopole or Dipole for 20 m field day with trees
I'm looking for some practical considerations on the relative merits of a dipole vs a monopole for 20 m. It's for a field station in the PNW, in a group campground with a 30 m circular clearing in the ...
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How will an off-centre fed (OCF) dipole perform 1ft over a lead flashing roof ridge?
We're fortunate enough to be fully renovating a mid terraced house in the UK. As part of the renovation I'm going to have the contractors run coax through the walls up to the roof where I want to ...
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Optimizing dumpvdl2 VDL2 ACARS Setup for Germany Using RTL-SDR
I am currently using dumpvdl2 with an RTL-SDR to receive VDL2 ACARS messages in Germany.
Setup:
Dongle: Nooelec RTL-SDR dongle, https://www.amazon.de/dp/B01HA642SW
Antenna: AirNav Radar UKW Airband ...
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30 ft telescoping fiberglass mast
I have a 30ft telescoping antenna mast. I am looking for a lightweight 20m antenna that I can use on the mast. Any help and instructions would be appreciated. I am going to be using it in a under ...
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Permittivity effect on antenna
I have found here that epsilon_r for Nylon is between 4 and 5.
For a helical dipole wound around a solid nylon cylindrical former, will there be any noticeable differences from the same helical dipole ...
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