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Old 04-27-2017, 6:25 PM
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Question antenna safety question

Would it be safe to use an outdoor scanner antenna if the antenna was grounded but the wire was to run directly from the antenna to the receiver without it passing through a ground block?
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Old 04-27-2017, 6:46 PM
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It depends.
What do you mean by "safe"?
What kind of antenna?
What is the antenna grounded to?
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Old 04-27-2017, 6:49 PM
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antenna is mounted to a chimney and the ground to a near by light fixture post
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Old 04-27-2017, 6:55 PM
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It doesn't sound to me like it would meet electrical code or industry standards.
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Old 04-27-2017, 7:09 PM
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Do a search on "NEC article 810" and you will find all the do's and dont's on how to ground an antenna to code.
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antenna is mounted to a chimney and the ground to a near by light fixture post
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Old 04-27-2017, 7:14 PM
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Had it installed earlier today by a communications company. Techs said it would be safe because the antenna is grounded well enough... Should I have the wire grounded as well before I start using it?
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Old 04-27-2017, 7:42 PM
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EDIT: I mean the coax cable is NOT grounded. It runs directly from the antenna to the receiver without passing through a ground block. the antenna mast is grounded and that wire is run to a nearby grounded light post on the side of the home. I have not hooked it to the receiver yet until I know for certain it is safe to use.
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Old 04-27-2017, 7:48 PM
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I have seen 3 chimneys hit buy lightning I would buy the best polyphasers money could buy.
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Old 04-27-2017, 8:06 PM
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Since this was installed by a "communications company" by a tech, who "...said it would be safe..." ????; won't touch this one.
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Old 04-27-2017, 8:15 PM
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What you're describing sounds like a disaster waiting to happen.

+1 on what prcguy said.
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Old 04-27-2017, 8:17 PM
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Quote:
Originally Posted by PGMAN89 View Post
Had it installed earlier today by a communications company. Techs said it would be safe because the antenna is grounded well enough... Should I have the wire grounded as well before I start using it?
Wow, not sure where to start with this.

Yeah, some installers cut corners, and they'll tell you it's "OK".

"OK" means different things to different people.

To some, OK means: No one died in the installation and it didn't cost me a lot.
To others, OK means: it was done well enough and I got what I think I paid for.
To others, OK means it was done correctly, to code, and there's no questions about it.

In the hobby realm, it's going to be one of the first two in most cases. Scanner listeners, SWL, amateurs, most of them never bother to ground anything. If they don't get a shock and their house doesn't burn down, that's considered OK.

In the professional realm, it's going to be the last two. Some installers will cut corners and call it good as long as they don't have to work late, miss lunch, get the boss mad at them, etc. Other installers know that they could be liable if they did the install incorrectly and someone was hurt, the house burned down, or an inspector would find fault with the installation.

What the installer did for you was take your money, do a halfway install, and while he did "ground" it, he didn't do it correctly. What he did would absolutely not pass an inspection. It does not meet the NEC. Your homeowners insurance might even take offense to it if there was damage to your home or a person due to this install. That might result in them not paying out, or they may not care.

Either way, it's not done to code, and that should be enough discussion.
But it won't.
Like I said, many people just stick the antenna up in the air and call it good.
Yes, you might not have any issues at all. No damage, no injury, no problem.
You might have noise issues. You might damage your radio from static electricity, a house wiring fault, a nearby lightning strike, etc.

In reality it comes down to what YOU want. Are you OK with what was done, or do you want it done to the National Electric Code standard?
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Old 04-27-2017, 8:19 PM
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Its unlikely you could ever ground your antenna system so your radio and everything electronic in your house will survive a direct lightning hit. My advise is to ground the antenna to NEC, then disconnect the antenna from the radio if lightning is on the radar.
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Quote:
Originally Posted by PGMAN89 View Post
EDIT: I mean the coax cable is NOT grounded. It runs directly from the antenna to the receiver without passing through a ground block. the antenna mast is grounded and that wire is run to a nearby grounded light post on the side of the home. I have not hooked it to the receiver yet until I know for certain it is safe to use.
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Old 04-28-2017, 3:34 PM
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Odds are that if the OP is in Bergen County, there are zoning codes and fire codes and such (i.e. the NEC) and that installation is not "up to code" because a lightning strike, or a loose power line, could contact the antenna and result in a surge directly into the premises.

Might be worth calling the communications company and just telling them the installation isn't up to code, it needs to be redone by a real technician, not just a guy with wire cutters.

The ARRL's book on proper grounding is available for $9.95 as a Kindle eBook, I think. Fast way to get a lot of information as to what "proper" installation is.
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Old 04-28-2017, 5:02 PM
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I'll add that if you call them and ask them to return and fix this, you'll likely get charged more.

Cutting corners was cheap. Doing it correctly is going to take some work and additional materials.

Avoiding this radio shop might be a good option, too.
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Old 08-12-2017, 12:09 AM
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Thanks to all for the comments ...
Up till now I've just taken a metal pole, clamped it to my house, put an antenna on top and hooked up the coax to my scanner.
I always listened most during a storm because that's when all the action happens.
Guess I've just been lucky.
I remember the lightning rods on the house roofs, but you don't see them anymore.
Out of sight, out of mind.
Thanks for the information ... I'll have to read up on how to do it right.
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Old 08-12-2017, 2:27 AM
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I would suggest browsing the PolyPhaser site white papers, they have several, one is for Ham Radio, unfortunately it has no drawings. Then there is the Motorola R56. It is pretty extensive and intimidating, just concentrate on the topic of single point grounding and bonding. You want everything referenced to the same ground potential, and that potential is your utility ground rod by your electric meter.

I had Dish Network install two dishes on my house. They used all the proper conductors pretty much, and a bonding block for the coax. BUT, they grounded to a ground rod next to my pool pump, that upon close inspection, was not bonded to the ground rod for my utility service.Just 3 feet away.

I corrected that and placed new 8 ft rods every 16 feet around the corners of the house and bonded them all together. If you are in an older house, the existing ground rod might be missing or has corroded to half its length.
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Old 08-12-2017, 6:02 AM
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I find these posts interesting from the difference US/UK perspective. We have much stricter rules on electricity supply than in the US as our supply voltage is higher, but lightning and grounding of antenna systems is totally unregulated - in fact none of our satellite and TV antenna install companies ground anything at all! Satellite dishes are a good example - usually twin or quad LNBs, cabled to the receiver. Most of our domestic electronics is now class II designed with no ground connections at all - so the set top decoder box is connected to the dish. Cable screen from the LNB, which probably isn't bonded to the dish metalwork. If towers are involved for hams, then the tower will be grounded. Any antennas will simply be attached - no special grounding. The usual discones and white sticks other people use will be on chimneys or on wall mounts and no grounding takes place. The only ground connection would come from any inside device that has an electrical ground. There are obviously a few people who do things differently - but the vast majority don't do it. All, our rules for grounding relate to electricity supply. We have various systems in use here, with the modern practice being protective multiple earths at the electrical intake - with neutral being bonded to ground at that point. We get a little sticky when like hams shacks, out buildings are supplied with power. Most times, a separate ground stake is used - connecting to the property ground system creates problems extending the ground zone - equipotential earth boundaries.

So reading this topic creates lots of questions. The US have rules on antenna grounding, and we don't. Some sites have their own rules, but that is contractual not electrical regs. Some towers require bonding top and bottom, or at the intake, while others don't. The aerials I have installed at quite a few Government towers were very unprotected - antenna fitted with the usual hardware, short length of 213 to N type connector, then down 4-50 to the radio room, short jumper to the radio equipment. No ground whatsoever. The Government systems would usually, but not always have gas discharge protection in line, but pretty much that was that. The upshot for me is that here, on top of a modest hill - there are 5 antennas and none of them are anything other than connected direct to the radios or cavities. Storms and lightning does happen - not regularly, but some last week, and I have never found it an issue.
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Old 08-12-2017, 7:48 AM
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Lightning strikes vary greatly by geography and weather patterns. Some places get hit hundreds of times per year, and some can go several lifetimes without getting hit. Here in the USA, there are several areas where lightning is common, and lightning damage is common enough that it's a concern for insurance companies--a significant part of their budget is paying lightning claims. And so the national rules reflect that.

If lightning strikes in the UK are a relative rarity overall, then it's not surprising that the rules would be more lax.
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Old 08-12-2017, 8:03 AM
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Ah - I didn't think about the insurance industry, I was simply thinking life threatening incidents, but with money involved I can see how this drives. Here, despite the software telling you of hits locally, it nevere really makes the news.
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Old 08-12-2017, 8:55 AM
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Here in central Florida, we have what's called the "Lightning Capital" of the USA. I had a direct strike on one of my antennas back in ~'92. It melted a small length off the main element; but for some unknown reason, it made that antenna receive better!!! But it took out all my speakers, telephone and a couple of worthless radios that were lying around though.
Knew that lightning was coming so I unplugged everything except for a couple of cheap CBs. My Yeasu FT-101EE and other expensive equipment wasn't damaged!
I had a mirror that was laying next to one of the coax PL259 connector that came from the antenna that was struck. The lightning traveled in through the coax, hit the mirror, burned off the metal back coating and broke the mirror in two! I still have that mirror to remind me of the consequence of lightning coming in to the shack.
UK undoubtedly get very few lightning storms and so I can see why there's less code requirements for grounding as such. Here, the insurance companies play a part in the codes. Last year I heard that a couple down the road lost their a/c and suffered some fire damage from a direct hit. THEY said the insurance company gave them a run around because their inspector didn't see a grounding wire in the a/c unit. I have no knowledge how true this is.
As for the OP, best bet is to follow the advice given about the NEC code.
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