Grounding my base antenna ?

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KD8NIV

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How do you guys ground your base antenna ?

In the past, I have just ran a stranded or solid copper wire from under the bottom U clamp where the antenna connects to the mast and run the wire down the pipe to the ground, where I then clamped it to a ground rod...

The coax, ran it into the shack....there I used a old piece of RG 213 coax and skinned all the insulation off the wires and twisted all the copper wires together and clamped it to a ground rod out side, which was a 5/8s solid copper ground rod and is in the ground 7"6".....RG 213 coax is clamped to this ground rod and it has a PL connector on the end inside the shack and I unhook the coax to the antenna and use a barrel connector to connect the coax to it.......

Is there a better way doing this...
 

majoco

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Wait...I can hear one of the "that doesn't comply with the NEC requirements" guys winding himself up to full steam before bursting into print......

Your grounding sounds pretty fine to me, although any old wire would do instead of the RG213 - but instead I would make sure that all the metalwork chassis of your radios is permanently wired to the ground rod. You can alleviate static build-up but you haven't got a hope if you get a real lightning strike!
 

prcguy

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Up to full steam now..... That doesn't comply with NEC requirements! Please take a look at NEC article 810 which can be found with a Google search and at least you will be informed on how to legally ground your antenna and why what you did may not be a good idea. Here is one of many examples on grounding antennas to code in the US: Installing radio and TV antenna systems | Code Basics content from Electrical Construction & Maintenance (EC&M) Magazine

Asking grounding questions on an Internet forum will get a dozen people giving a dozen different ways to ground an antenna and some of the advice in the past has actually been dangerous. Read up on what the code is and then you can ground to code, or not, but at least you will know what your supposed to do.

I was a certified trainer for residential satellite antenna installers and with that had to know how to legally ground stuff, but I'm not going to tell someone how to properly ground an antenna on a public forum beyond maybe pointing out something that is obviously not ok. And thanks to majoco for the opening line, I think it should be used more often rather than giving specific advice that could get somebody hurt or sued, etc.
prcguy

Wait...I can hear one of the "that doesn't comply with the NEC requirements" guys winding himself up to full steam before bursting into print......

Your grounding sounds pretty fine to me, although any old wire would do instead of the RG213 - but instead I would make sure that all the metalwork chassis of your radios is permanently wired to the ground rod. You can alleviate static build-up but you haven't got a hope if you get a real lightning strike!
 
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KD8NIV

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Grounding my antenna

I did Google my question, and like you mentioned had a bunch of different things to come up....was hoping to hear from you guys on how you grounded your antennas....

I'd like to run what length of coax it would take to come from the antenna to the ground with my coax, and put a break in my coax here, and use a barrel connector to connect the coax to a ground rod....like this idea, only thing is once the storm is over how would you reconnect the coax to the antenna and keep the moisture out ?

It cant be a perment something to seal this connection, any ideas on this ?...
 

prcguy

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If you install a new ground rod, the building code requires you to bond that new rod to your existing house ground in a very specific way. That's why I gave you a link to check out.

If you don't bond the new ground rod to your existing ground there could be a dangerous difference in potential between your coax and the house ground that can hurt you in some cases. I did that once and there was 90v on the coax that would hurt like hell when you had one hand on the coax and another on anything grounded in the house. Plus if you get a direct hit on your antenna there can be more damage from thousands of volts difference between the separate antenna ground and the house ground, causing more damage.

There are various companies that make lightning arrestors that will give you a grounding point for the coax to a ground rod and a female connector for the cable from the antenna and one for a cable to the radio. I like the Polyphaser brand but there are others like Alpha Delta, I.C.E.,

Its common for people to disconnect the antenna cable from the radio during a storm but I think its odd to disconnect the cable outside at the lightning arrestor every time a storm goes by.
prcguy


I did Google my question, and like you mentioned had a bunch of different things to come up....was hoping to hear from you guys on how you grounded your antennas....

I'd like to run what length of coax it would take to come from the antenna to the ground with my coax, and put a break in my coax here, and use a barrel connector to connect the coax to a ground rod....like this idea, only thing is once the storm is over how would you reconnect the coax to the antenna and keep the moisture out ?

It cant be a perment something to seal this connection, any ideas on this ?...
 

KC4RAF

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As prcguy posts.

The ground rods MUST be all tied together. Reason? Because you can get a different voltage between the ground rods, this then adds potential to damaging voltage to your equipment.
I am a retired electrician, with a master's degree and a retired electronics tech. You can listen to others who say there's no harm in their way; or you can do it the right way and have much better chance of no damage to your equipment. Your choice.
 

ab3a

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I have a full head of steam now! Let me say this with all the authority I can as a registered professional engineer.

>>> BOND THE GROUND RODS TOGETHER!!! <<<

If you do not, you will destroy a lot of things when lightning strikes nearby, You may even burn down your house. I've seen incredible damage happen in my career.

I can explain this all in detail offline but the bottom line is that you should bond the ground rods together exactly as described in the NEC. These rules came about from many bad experiences. Do not ignore it.

Jake Brodsky, PE
 

PrimeNumber

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Got it, bond rods, thanks. I'm in the middle of a big antenna upgrade anyway, it's the peak of lightning season, things are overdue for this. It's not just code, it also makes sense.

Here's my question: What gauge wire to use?

Here's the background to my question: I have two planned antennas each about 50' distant in different directions from the shack's pass-through panel. They'll each get their own ground rod which will each receive their Very Own Bonding Cable (peace be upon them) back to the shack's ground rod. It all runs on off-grid solar, so there is no connection to the house's electrical ground system. OTOH, I can always run another bonding cable to the grid electric's ground rod, it's only about 25' away from the shack's rod.

How much current will these things have to cary under typical operating loads from a barefoot 100w rig? In the event of a direct hit, copper bonding wire of any practical size will probably be converted into a plasma channel, so does the size even matter then? In the event of a near strike, there will be some significant current, but it will only be momentary. Is 6 gauge stuff really needed, or will something like 12 gauge (of which I have a near-infinite supply) do the job?
 
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