Use this tag for questions relating to protection of equipment from undesired external inputs such as overvoltages, RF coupling, and other potentially damaging inputs.
Questions tagged [equipment-protection]
17 questions
25
votes
6 answers
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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12
votes
3 answers
Protect rig from static charge on antenna
How can I continuously discharge static from my end-fed antenna?
My Electraft K2/100's autotuner (schematics) has an SWR bridge using two 1N5711 pin diodes. These diodes get blown if any static builds up on the antenna. I've replaced them four…
Wayne Conrad KF7QGA
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9
votes
1 answer
How effectively do modern transmitters protect against high SWR?
The following are fairly common knowledge:
Transmitting at full power with too much of an impedance mismatch can damage your finals.
If we do so inadvertently, modern radios drop the power significantly for self-protection.
Yet, it's still very…
Dominick Pastore
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8
votes
3 answers
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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8
votes
2 answers
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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7
votes
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Is it safe to mount an active scanning antenna close to an hf antenna?
I live in the centre of a seaside town in the UK. Because of lack of space I have a random wire antenna in the loft of a small house, and pick up a lot of noise on the top band Sunday morning CW ragchew. I am about twenty hilly miles from most of my…
Harry Weston
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6
votes
2 answers
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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6
votes
2 answers
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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5
votes
4 answers
Recommended way to analyze spectrum output of a high-power amplifier?
I have a small collection of "software defined RF lab" equipment, notably a HackRF and a VNWA3. I am almost done building a 35W HF amplifier and once I've done some other testing, would like to look at the spectrum of the final output as a…
natevw - AF7TB
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5
votes
2 answers
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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4
votes
5 answers
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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4
votes
2 answers
Setting up an Outdoor Antenna
If I would buy a ham radio with an outdoor antenna, what would I need to do to make it work (e.g can I just stick it outside) especially because I live in Miami and Miami doesn't exactly have the best weather?
Would putting an outdoor antenna…
hopefulhacker-Reinstate Monica
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3
votes
2 answers
Adequate lightning protection for sloped dipole or G5RV?
Has anyone had experience, or knows from first principles, whether installing a G5RV or dipole BELOW a "lightning-rod" in such a manner would serve as a means of discouraging direct lightning strikes onto your dipole:
A "lightning rod" is some…
Warren VE3WPX
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3
votes
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What steps to take to secure for G2 geomagnetic storm?
So I see NASA has issued a geomagnetic storm watch for a possible G2-level storm on the 11th. I’m at about 53 degrees north geomagnetic latitude.
Is this something I need to care about equipment-wise? Should I disconnect my IC-7300 from the antenna…
QuantumMechanic
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3
votes
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Can Yaesu FT-65 be charged from a 12 VDC automotive accessory outlet?
I recently purchased a Yaesu FT-65 handheld radio and quickly discovered it had no 12 VDC power port like other handheld radios I've seen. The charging cradle uses a 12 VDC wall wart for power, and the radio sits in the cradle to charge, there's no…
MacGuffin
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