Skip to main content

Questions tagged [grounding]

Use this tag for questions relating to RF and DC grounding in radio equipment. Specifically suggested methods, practices, equipment and regulations regarding grounding.

Filter by
Sorted by
Tagged with
20 votes
2 answers
15k views

How to detect common-mode currents or “RF in the shack”?

Let's say we already know that if your antenna is not suitably constructed or connected then you can get current on the shield of your coaxial feed line which will flow through the shielding/grounding ...
Kevin Reid AG6YO's user avatar
  • 24.6k
13 votes
3 answers
10k views

How do I prevent radio signals from tripping a GFCI?

My wife woke up several nights by a metallic "thunk". It happened to be while I was talking on 10 meters and turned out to be the ground fault circuit interrupter (GFCI) on her hair dryer cord. ...
Peter KB1AVL's user avatar
13 votes
4 answers
4k views

Handheld Dipoles

A problem with handheld devices is poor grounding. I read from someone else's question that dipoles don't need a ground. Why don't they make little handhelds with two antennas instead of one, or a ...
Skyler 440's user avatar
  • 7,600
13 votes
2 answers
12k views

When is RF grounding necessary, and when is it not?

I've seen many installations, particularly at field day and also in second-floor installations, where RF grounding is ignored entirely. What are the drawbacks to this and when is it absolutely ...
Bill - K5WL's user avatar
  • 1,194
12 votes
5 answers
8k views

Grounding a second-story shack with an outdoor antenna

My shack is on a second story, really far away from the house ground. To run a ground from my equipment to the outside/ground is a run of at least 60-75 feet. The antenna is at least 100 feet away as ...
Jay's user avatar
  • 121
11 votes
5 answers
34k views

Should I ground my radio to the chassis or battery for a mobile install?

From what I've seen, there are generally two ways to power a mobile radio: Positive lead to battery, negative lead grounded to chassis Both positive and negative leads to battery I know that ...
Ben's user avatar
  • 213
10 votes
2 answers
11k views

Grounding VHF base station antenna

I'd like to install an outdoor dual band VHF/UHF base station antenna, a simple pole antenna like the Comet GP-1. I live in an area where lightning is rare, but not unheard of. Should I drive ground ...
Johnny's user avatar
  • 203
9 votes
2 answers
4k views

What causes ground losses in a HF antenna system?

This applies to mobile and fixed installations. What are ground losses, and how can they be minimized? It seems to involve proximity to the ground, but what is the mechanism that causes loss? Does ...
Bill - K5WL's user avatar
  • 1,194
9 votes
2 answers
2k views

What are some ways to ground a transmitter+antenna in an enclosed attic?

If I want to minimize "RF in the shack" and lightning hazard, what some good ways to ground a transmitter and indoor antenna in a top floor room or attic with no exterior access? (say a multi-story ...
hotpaw2's user avatar
  • 13.4k
8 votes
3 answers
3k views

What is the proper way to ground your station's antenna?

I don't understand how you would go about giving an RF ground to your antenna. Would it not become an additional radial and affect the signal? What is the proper way to ground your station's antenna?...
David Anastasio's user avatar
8 votes
1 answer
69 views

Testing a possible grounding point?

Some multi-story buildings in my region require earthquake isolation on some of the piping. Thus my question. Is there a way to determine whether a nearby metal water pipe is actually Earth grounded,...
hotpaw2's user avatar
  • 13.4k
8 votes
5 answers
2k views

Coax fed dipole: shield goes to one side, yet is grounded via chassis line to Earth

Suppose I have a coax-fed half-wave dipole antenna. The coax shield goes to one side of the antenna, the center conductor to the other side. The transceiver's chassis is connected (via the coax ...
Jack's user avatar
  • 81
8 votes
2 answers
470 views

Why is an RF ground not as critical as the other, and can they be used backwards?

I will give the magmount antenna as an example: The vertical element to the antenna is very critical, cut to a certain wavelength, often added with some loading coils, or a little spiral to make ...
Skyler 440's user avatar
  • 7,600
7 votes
5 answers
4k views

Using Earth as an RF ground

I have built a simple ground plane antenna for 70cm with a connector, 4 radials, and one vertical element. The RF ground is connected to the radials, and the RF is connected to the vertical. It got ...
Skyler 440's user avatar
  • 7,600
6 votes
5 answers
2k views

Grounding a vertical antenna from a balcony

I have a multiband vertical antenna mounted onto the railings of my balcony apartment high up on the 6th floor of an apartment building. The antenna is not grounded. This antenna comes without radials....
Engineer999's user avatar
6 votes
2 answers
229 views

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 ...
User5754448's user avatar
6 votes
1 answer
135 views

How to ground with little surface area?

Let's say I have a very small device, like an RC airplane, which transmits information as well as receiving commands for control. The body is made out of non-conductive foam, therefore not much ground ...
Skyler 440's user avatar
  • 7,600
6 votes
2 answers
4k views

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 ...
Adam Davis's user avatar
  • 12.1k
5 votes
2 answers
907 views

How do I interpret the FCC ground conductivity map files?

The FCC has .seq files that show ground conductivity which it makes available for download. Unfortunately, there doesn't appear to be any documentation that comes with the files, or even headers. I ...
user3486184's user avatar
  • 1,957
5 votes
4 answers
7k views

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+ ...
user avatar
5 votes
1 answer
711 views

How can I counter DC-DC inverter noise / ground noise in an electric-vehicle mobile setup?

So, I'm relatively new to all this; and I've gotten an ICOM IC-7100 on sale, which looks like an excellent transceiver … unfortunately, this very specific line shows up in the manual: The ...
ELLIOTTCABLE's user avatar
4 votes
5 answers
4k views

Do modern radios and power supplies require grounding for safety?

Do modern radios require grounding to be used safely? All I am concerned about is not getting electrocuted when I attempt to use the radio. I'm not concerned with RFI or Lightning safety at this point ...
Nick H's user avatar
  • 143
4 votes
2 answers
826 views

VNA basics, antenna coax cable

Recently purchased my first VNA (Nano VNA) and I'm trying to learn the basics. I have a 150MHz 1/4 wave whip antenna that I need to install on a large metal object so I was hoping to use a VNA to help ...
P_J's user avatar
  • 43
4 votes
2 answers
4k views

Can I connect my station ground to my house's ground rod?

I'm setting up my first HF rig and I'm reading a lot of conflicting information regarding station grounding. Can I connect my HF rig/station's ground to my house's ground rod or do I need a stand-...
SomeGuy1989's user avatar
4 votes
5 answers
843 views

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 ...
kr4sh's user avatar
  • 367
4 votes
2 answers
275 views

Mounting a hex beam on top of a high urban building

I am moving into a new apartment in the city soon which is on the 24th and last floor of an apartment building. I will have access to the roof of the building also. I'm still trying to understand ...
Engineer999's user avatar
4 votes
1 answer
2k views

Antenna, input and ground bonding

I'm new to this and am in need of guidance. I am mounting a multi-band antenna on a 50 foot tall 1 1/4" galvanized mast. I plan to drive a ground rod at the base of the antenna and bond the mast to ...
user avatar
4 votes
1 answer
2k views

Bonding of Coax shield to RF ground conductor for long ground runs?

My shack is on the second floor of my home, and I run a single operator, 2 radio contest setup. The two coax runs pass through the wall and drop down to an antenna switch approximately 15 feet from ...
Hamsterdave's user avatar
  • 1,844
4 votes
1 answer
540 views

Easy Digi hum with isolated ground

I am creating an Echolink simplex link using a Raspberry Pi 3 B+, a Pluggable USB sound adapter, and an "Easy Digi" sound card interface which has 2 - 600ohm isolation transformers for audio in/out as ...
john8791's user avatar
4 votes
5 answers
10k views

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 ...
Projectile Fish's user avatar
4 votes
2 answers
5k views

Can I ignore the radial elements of a 2m/70cm antenna if it's on a metal roof?

I'm looking for a dual band base station antenna, and find that many of them have short radials around the base. Due to the specifics of my installation, I need to remove them. However, it is being ...
Adam Davis's user avatar
  • 12.1k
4 votes
2 answers
4k views

Does effective grounding of mobile (vehicle) antenna mounts address common-mode currents?

While researching how best to install my mobile amateur radio in my car, I didn't understand if there was optimum Antenna Feedline Length for mobile installations? Understanding that this is caused ...
BenSwayne's user avatar
  • 691
4 votes
1 answer
200 views

What are the consequences of poor station grounding?

What can happen if I don't properly ground my equipment?
JC Hulce's user avatar
  • 901
4 votes
0 answers
854 views

4NEC2 radials & grounds

Teaching myself 4NEC2 and have most of it under control, which is good. Regarding radials & grounds, i've been learning the "rules" NEC(2) has, summarised below. 4.1. Free space. In the ...
t252's user avatar
  • 697
4 votes
3 answers
629 views

RF ground confusion

I'm a bit confused by RF grounding. Let's take a HF 1/4 wave vertical antenna for example. When current flows through the centre of the coax to the antenna, my understanding is that the current then ...
Engineer999's user avatar
3 votes
3 answers
590 views

How do I get my crystal radio to receive?

My 8 year old and I are trying to figure out how to get this crystal radio we made working. It's based off this youtube video. We get clicks when we put the crystal ear piece either side of the ...
Agent Zebra's user avatar
3 votes
4 answers
3k views

Lightning protection by disconnect

Currently I am evaluating options for my antenna's in regards to lightning protection. My setup is a physical disconnect of all my antennas using an outside "patch panel". So every time I power up ...
Edwin van Mierlo's user avatar
3 votes
2 answers
934 views

How to establish RF ground for 1/4 wave vertical in apt on 3rd floor (about 35ft above the ground)

I am struggling to understand how to introduce an MFJ-931 artificial RF ground into my current system and am hoping for some help to sort out best practices. Although my use-case seems pretty common, ...
A Bit of Help's user avatar
3 votes
2 answers
783 views

Understanding "ground" in ham radio

What is a good explanation of the different "ground" types that hams deal with? Specifically: grounding an antenna mast/tower (outside, lightning prevention) grounding transceiver/equipment (inside ...
Ron J. KD2EQS's user avatar
3 votes
2 answers
757 views

Connecting copper strap to grounding rod

Is there a way I can connect a 2"x.025" copper strap to a 5/8" grounding rod that can be buried? I've seen the bolt-on strap clamps, but those need to be inspected periodically. I've ...
Brad Mace's user avatar
  • 421
3 votes
1 answer
310 views

Bonding ground rods for lighting protection

I am installing 2 antenna masts on one end of my house. The utility ground is on the far end of the house, and was buried under the asphalt driveway. Working with my electrician, he suggests 2 ground ...
mbond's user avatar
  • 97
3 votes
2 answers
2k views

Grounding a chimney mounted antenna

I'm installing a new antenna mast to hold one or more antennas. The new mast will be strapped on to a chimney near the center of my house. Coax will run down the mast, across the roof, down the side, ...
Adam KC0DAD's user avatar
3 votes
2 answers
2k views

Antenna installation for a base station

I have a detached garage that is approximately 15 feet high. The garage is approximately 20 feet from my home I will be using a Kenwood D-710GA radio, a Grandmaster SWR Meter and a 6 foot comet GP-3 ...
Jeffrey Pelkofer Sr's user avatar
3 votes
2 answers
98 views

Should the earth rod be incorporated in the total length of an RF grounding system?

I have installed a grounding system just outside my radio shack and was careful to avoid a quarter wavelength or multiples thereof (for single band use), or anything in total length that is close to ...
Francis Archibald's user avatar
3 votes
1 answer
631 views

What are the effects of a ground plane under a horizontal dipole?

What are the effects on signal propagation if this ground plane is just a metal object and what are the effects if the ground plane is actually grounded? I am asking this question because someone ...
Synaps3's user avatar
  • 425
3 votes
1 answer
245 views

Electrical Earth

I have moved to a new flat which is on the 4 floor, luckily the landlord has let me put an OCF dipole outside with coax feeding through an existing hole in the window frame. I'm looking for some ...
user7286370's user avatar
3 votes
2 answers
738 views

Not-too-distant saltwater ground

Problem I'm planning on mounting a vertical HF multiband antenna on the edge of my roof. Due to the presence of a paved walkway and some other similar property constraints, I have no room for ...
Eric's user avatar
  • 133
3 votes
3 answers
1k views

Baofeng radio produces hum when plugged into charger

So I am working on a low cost ham radio beacon using my Baofeng UV-5R radio because it is easy to use and portable. I built a simple PTT interface for a Raspberry Pi and wrote some python to transmit ...
MrSchmuck's user avatar
3 votes
2 answers
602 views

HF vertical 1/4w antenna on a tin roof?

I would like to build a 1/4 ~ vertical antenna on my tin roof for a ground plane. Does the angle of the roof matter? Should the antenna be vertical, or perpendicular to the roof? Would it be better ...
marc's user avatar
  • 33
3 votes
1 answer
401 views

Grounding for lightning safety - upper floor (UHF/microwave antennas)

I have some UHF, microwave antennas and an antenna rotator on a roof mounted mast. The "radio room" is in the second floor just below the antennas. Also the service entrance for building electricity ...
rubund's user avatar
  • 224