Well on commercial sites like hospitals or communications sites they do this. Every piece of metal on the roof of the building gets connected to lightning conduction wires that go to the external ground ring, until the whole roof looks like a web of wires. In addition, every piece of metal (grates, fans, etc) in equipment rooms get connected to the interior perimeter ground bus. The ground system is also connected to the structural steel of the building. This guarantees that the lowest impedance path is through the ground system, but damage could still occur if a strike overloads the ground system and branches into undesired paths, or that the strike inducts harmful currents in nearby wires.

Picture: A roof at St. Olavs Hospital in Trondheim, Norway. Each fixture has its own ground wire, and the roof is ringed with wire too.
http://i50.tinypic.com/14loux0.jpg

Not something for the average ham, of course. An important point to take from your post K1CJS is that lightning can arc through air - after all it passed hundreds of meters from the cloud already.

WX7G, insisting on a single entry point for AC and antennas can lead to bad solutions if you don't do it right. For example, if the antenna is situated on the other side of the house to the AC service entry, and you decide to run the coax to the AC service entry by hanging it on your exterior wall halfway around the house, a transient could arc through the wall to the house wiring or induce current in it. Having a separate AC and antenna entry, well bonded together, is preferable to a poor execution of a single entry.

Even if done right, running the extra coax could mean more losses that you don't want.

#6 AWG sounds a bit too small for an external ground ring, for bonding the AC and antenna ground. The Motorola R56 standard document (2005) calls for #2 AWG, or perhaps #1/0 AWG in lightning prone areas, with reference to ANSI T1.313-2003 and ANSI T1.334-2002.

I'm not an electrical or radio engineer - my degree is software oriented - but I've read enough about lightning protection to realize how tricky it is to run calculations on it. The idea that a strike will just equally divide itself among a number of ground rods without consideration to their physical distance or the impedance (resistance and reactance) of the connectors between them, or the ground resistance, still strikes me as overly simplistic.

Ignoring the impedance of the house wiring and coax, and the ground system impedance, seems to me to make the scenarios too simplified. Scenario 1 (no outside bonding of AC and antenna ground) would still be a very bad thing, but not because one 6th of the lightning that strikes the tower will go through the house. It wouldn't, I think. In case of a tower strike, you could indeed get excessive lightning current flowing on your house wiring - or the plasma it leaves behind - but not one sixth of the tower strike.

I would be at least as worried about a transient (such as a neighbor's electrical fault, transformer fault, or lightning strike) coming in on the AC wires, going through the house, and seeking your excellent antenna ground through the house wiring.

Having a single entry point for all cables (scenario 3) is indeed the ideal situation, but if you have sufficiently low impedance perimeter ground cables bonding the coax entry and AC entry grounds together, it would reach the same level of protection. The drawback is that it would need more copper wire than having a single entry for all cables; the advantage is that the extra copper could cost less than it would cost to rebuild the house.

AD5ZC's advice leads to electrocution and fires. It's not many months ago when three family members were killed while erecting an antenna that contacted high voltage power lines, and OSHA has a long list of fatal accidents involving overhead power lines. Most involve direct contact, but some involve arc flashes. (Suggested keywords are "electric arc" and "overhead power lines").

If you bring a wire antenna under high voltage power lines, you can induce enough power to light a lightbulb. If you have an antenna that doesn't bleed static, you might get a bit of spark gap action going in your antenna system or in your radio.

Asking a random police officer for a legal opinion on a specialist matter might give a good result, but it might not. You could get a wrong answer, or you might even have difficulty extracting a statement, because it might be construed as being legally binding. If you really need to know, hire a lawyer licensed in your area.

The rules are pretty clear though, so let's look at them.

What we're discussing here are really three different scenarios:

Scenario 1: Trained amateur radio operators participating in organized emergency communications, assisting public officials. They are ham radio operators, but they are also authorized. In this case, if the amateur needs to talk on police/fire/EMS frequencies, it makes sense to give them access to an approved and appropriately configured radio of the same type as the dispatchers or mobile units use, and give them at least a subset of the same training as a regular dispatcher. In some areas, their amateur volunteers are given dispatcher training, or they are sitting right next to the dispatcher.

There's no individual operator license in part 90 public service radios, the licensee (for example the police or fire department) is responsible for making sure that the radios are in good working order and used according to the license by training and authorizing.

Scenario 2: A situation might emerge where the trained communicators in scenario 1 need to use non-approved equipment to save lives and property, because the part 90 equipment malfunctions or is operating out of specification. Part 90 allows this:


Scenario 3: A random citizen in grave distress calling for help, by operating an amateur station out of band or operating without a license. In this case, even if there wasn't a statute to lean on, one could use necessity as legal defense if subject to misguided prosecution. But you won't need to do that because both part 90 and part 97 already covers this and makes it legal to use both amateur and public service radios out of band/service in real emergencies.



So out of band operation in a real emergency is in accordance with both the public service and amateur license rules.

In addition to this, there are general rules (for all FCC services) in part 2 relating to emergencies, particularly
§2.401 Distress messages.
§2.405 Operation during emergency

Note that §2.405 does NOT apply to amateur radio or broadcasters, because part 97 and part 73 contain their own rules for emergency communications, and §2.405 is more restrictive than what part 90 and 97 allows. For example, when conducting emergency operations under §2.405, one has to send a notification to the FCC every time, unlike in the amateur service.

You must of course use common sense as well - if you're calling about a house fire without lives at risk, don't interrupt communications about a fire where lives are at risk or undetermined.

For what it's worth, the OSHA minimum distances between a worker not qualified for high-voltage work - or a metal object - and energized power lines are

VE3FMC, I would have loved to see pictures of that setup.

Are you feeling OK there, W4HLN? You seem distressed, and without any arguments to support your assertion.

The President has the power to shut down amateur radio, as in WWII, but he already has that power by law. This new executive order doesn't change that at all. The President can't grant himself powers he doesn't already have, and yes the Constitution and the law still applies in an emergency.

You evidently didn't properly read and understand what you pasted.
What's being talked about here is taking frequencies from one federal agency (military, DOJ, etc.) and giving them to another, if needed. This is the spectrum managed by the NTIA, not the FCC.

The federal government is bound by the law even in emergencies, but the law may give them greater powers in a state of emergency.

Even in an emergency, laws have to be followed, but they have emergency powers that lets them do more than they otherwise would.

By the way, for international readers, it might be interesting to know that frequency coordination in the US is split into two. The NTIA, which is under the President, allocates frequencies to government agencies, and also to foreign embassies. The FCC, which is an independent body with members confirmed by the Senate, assigns frequencies in the commercial and private radio services like marine radio, amateur radio, broadcasting etc.

One way of looking at this is that your garage is already near the power lines, and it's probably connected to your house by low voltage lines - if the power lines fall down your antenna might not make much difference in the damage caused to your house and garage.

However, I would not put the antenna on that side of the house. High voltage power lines have an electric and magnetic field around them, and I'd personally consult a qualified engineer before putting up antennas, or anything metallic, under a high voltage line.

He's saying that some of the parts are made in China, and that the Chinese illegally make copy products. The real Honda engines and generators are still made in the US.

I don't know how often it happens with generators, but failed production runs from a factory - which should be destroyed - tend to go out on the black market. I've seen it happen with clothing and plastic shopping bags for example.

You can get good stuff from China, but make sure it's a brand or store that can stand by its warranty, and has some degree of quality control.

Thanks G3TXQ. KI4SDY is on many ignore lists himself. I have short "do not call" with people who have displayed abusive behavior on the air or online. KI4SDY's note field contains "BIRF SIRTIFIKIT! OBAMA! and generally off topic poster on eham.net"

Running balanced line all the way to the tuner will easily eliminate high SWR losses in the coax, as W0BTU says, but you still have the problem of many lobes and nulls on the lower frequency bands. To avoid that, you might consider a trapped dipole or a fan dipole.

PS: KT0DD, it's a bit confusing when you start making new threads to continue the same conversation. Can you keep each topic in one thread?

I'm not experienced with towers, but I don't quite understand. I thought LMR-400 would be good for HF; perhaps not cost-effective, but low loss. Perhaps somebody else could weigh in on this.
I'd understand if they discouraged any form of braided coax, and instead recommended heliax coax; that's good advice for remote commercial sites, since rusting coax braid can cause non-linearity, and thus intermodulation. However RG213 and RG-8X also have braided shields. Does the foil and braid in LMR cable start rusting and acting non-linearly before coax with just braid?

Even if it turns out that one of the access points is affected by your transmission, winding the DC power cord on a couple of ferrite beads, replacing the power supply, or plugging it into a different outlet, could cure the problem. Check the RFI/EMI forum for more information.