Amateur Radio Stack Exchange
Amateur Radio Stack Exchange

Questions tagged [lightning]

Questions about lightning safety, mainly in regards to antennas and feedlines

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How can I protect equipment against a lightning strike?

A lot of aerials (almost by design) would be rather good attractors of lightning. What steps do I need to take in the field to keep my gear safe against a lightning strike? I'm presuming the obvious already here (such as not operating in a storm),…
berry120
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Do lightning rods attract or do they help prevent lightning?

I'd read that the current theory of how lightning rods protect a house, antenna tower, or other structure is by preventing lightning from striking -- that is, the sharply pointed rod lets charge dissipate from the structure, so that it doesn't build…
Zeiss Ikon
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How to keep a disconnected coaxial connector weatherproof?

The advice I have seen on lightning safety is that if you don't have high-quality lightning protection (and associated grounding) installed on your feed line, it is advisable to, during a storm and preferably whenever you are not using your station,…
Kevin Reid AG6YO
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DIY lightning arrestor - gap size?

I have an antenna that's well above the treeline, and I've heard I can add some small amount of protection by placing two bolt heads a short distance from each other, one connected to the antenna, the other connected to the ground rod. What distance…
Adam Davis
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Lightning Dissipators

I have heard about many lightning protection strategies in the shack, but nobody mentioned the lightning dissipator. The lightning dissipator consists of many small spikes and prevents a strike by slowly discharging through each little spike.…
Skyler 440
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Where can one get a "listed" SO-239 lightning arrester?

According to this summary of NEC requirements for radio antenna grounding (from 2014, but hopefully still somewhat accurate): https://www.mikeholt.com/files/PDF/Radio_and_Television_2014NEC.pdf It says "Antenna lead-in surge protectors must be…
User5754448
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How do Field Day participants protect from lightning?

I'm planning to attend Field Day this weekend, and the forecast calls for thunderstorms. I can picture a serious issue with a bunch of temporary antennas set up in an open area when a thunderstorm sweeps through. This seems to have the potential…
Zeiss Ikon
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Lightning strikes nearby and coaxial cable

A direct hit on my home by lightning is very, very unlikely. However, many lightning strikes that hit Earth nearby are by far the main hazard for ham radio gear (in my opinion, after 60 years in the hobby). The huge electromagnetic pulse generated…
user10987
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I am installing a ham radio and want to properly ground it

I am installing a ham radio and want to properly ground it. I will be including a lightning arrester that will also go the the ground. I will have a 20' mast with a long wire antenna running 130+ feet out to the south. The far end will be about 45…
Chris Baker
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What are these antennas?

On a recent trip to China I photographed a number of "antennas" that I do not recognize. Are they even antennas?
VE3LNY
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Colocated three orthogonal wire loops for lightning detection network

I'm considering building multi-turn wire loop receive antennas for a blitzortung.org lightning detection receiver. It has three separate channels for H-field antennas, operating simultaneously. Typically, only two orthogonal loops in vertical…
Xpector
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Grounding a dipole

How do you properly ground a dipole (RX only for VHF scanning) to protect it against ESD/lightning? In my set up i'm putting a dipole on my roof. I've connected the two dipole elements together with a 100k resistor, and have a balun and amplifier…
Projectile Fish
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Antenna grounding / bonding in relation to my AC service (with pictures)

I'm trying to figure out how to properly connect new ground rods for an antenna to my main panel. Any advice from those who have done this + have great electrical knowledge would be greatly appreciated. I plan on hanging a dipole from a tree near…
kr4sh
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Electromagnetic signal from spark gap

I am a power electrical engineer college student, and I have a project to make an antenna for magnetic direction finding. My main topic is to detect lightning strikes, but its to hard due to randomness of the lightning occurence. So my lecturer…
Ramanda Nvl
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Is this transmission line peak voltage formula published in CQ Magazine more accurate?

In his July 2018 article in CQ magazine entitled “Lightning (and EMP) Surge Protection for HF Radios”, Steven Karty, N5SK based much of his analysis for properly specifying a GDT (Gas Discharge Tube) on an equation used by Huber+Suhner (S+H) and…
Glenn W9IQ
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