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Amateur Radio Antennas - For discussion of all amateur band designed antennas and related accoutrements. This includes base, handheld, mobile and repeater usage. For commercial antennas on the amateur bands please use Commercial Radio Antennas below.

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Old 06-07-2017, 12:51 PM
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Default Antenna and ground

at which point you ground your antenna? I look at this thread here and really want to move my antenna mount from lower point of my roof to the one like this thread before, but I seem to can't figure out where this person ground his antenna ground. look like he has the cable go all the way into the house from the antenna

https://forums.radioreference.com/sc...ting-idea.html

if I had PolyPhaser - Bulkhead Arrestor N/F (IS-B50LN-C2) for light protect, can I ground that with my inside ground electric ground or have to be outside ground like I read else where?

try to put up repeater system for private use and my build thread question is here

https://forums.radioreference.com/ra...onnection.html
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Old 06-07-2017, 9:48 PM
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Depends on your exact antenna, but "usually":

The antenna mounting pole should be grounded, as should the outer shield of the coax. In commercial installs, the coaxial shield is grounded near the antenna base, at some interval coming down the tower and at the base of the tower.

The Polyphaser should be installed where the cable enters the structure.

Lightning ground is different from your house internal safety ground. Do NOT ground your antenna to your electrical outlet grounds.

What you need is:

Lightning travels a long way, and a little bit of insulation, etc. isn't going to stop it. Lightning is trying to find the quickest path between cloud and the earth. You want a direct and straight (as possible) path to ground for your system. That means that you ideally want a heavy gauge conductor (6 gauge or bigger) running straight down from your antenna support to at least one ground rod directly under the antenna. This should be your system ground. Support pole/tower, coaxial shield and polyphaser ideally should all be connected to this rod (or rods, depending on local ground resistance). Also, the National Electric Code requires that all your grounds be bonded together. Running a 6 gauge or larger conductor from the radio ground rod to the house electrical ground rod is required.

Ideally you should be talking to someone who can design a proper ground system. It's not necessarily something that can be designed properly via an internet forum. There are a lot of variables. To do it correctly requires a professional with knowledge of the location.
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Old 06-08-2017, 12:32 PM
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Quote:
Originally Posted by mmckenna View Post
Depends on your exact antenna, but "usually":

The antenna mounting pole should be grounded, as should the outer shield of the coax. In commercial installs, the coaxial shield is grounded near the antenna base, at some interval coming down the tower and at the base of the tower.

The Polyphaser should be installed where the cable enters the structure.

Lightning ground is different from your house internal safety ground. Do NOT ground your antenna to your electrical outlet grounds.

What you need is:

Lightning travels a long way, and a little bit of insulation, etc. isn't going to stop it. Lightning is trying to find the quickest path between cloud and the earth. You want a direct and straight (as possible) path to ground for your system. That means that you ideally want a heavy gauge conductor (6 gauge or bigger) running straight down from your antenna support to at least one ground rod directly under the antenna. This should be your system ground. Support pole/tower, coaxial shield and polyphaser ideally should all be connected to this rod (or rods, depending on local ground resistance). Also, the National Electric Code requires that all your grounds be bonded together. Running a 6 gauge or larger conductor from the radio ground rod to the house electrical ground rod is required.

Ideally, you should be talking to someone who can design a proper ground system. It's not necessarily something that can be designed properly via an internet forum. There are a lot of variables. To do it correctly requires a professional with knowledge of the location.
Thanks for the answer, from what I understand reading from other forum is all the ground from antenna, from tower and from polyphaser need to be bond togetther to a separate 6 feet deep copper ground with at least 6 gauge wire, this is pretty much what you were saying too.

however, when using with EMT mast I am not sure if that 6 feet deep need for the ground. I also read somewhere that this separate ground need to connect to connect to house ground main entry point.

what about radio ground ? can I connect to house hold ground since it is in side ?
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Old 06-08-2017, 8:42 PM
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Xccess- Here is a good publication by the IEEE which details in layman's terms, the art and science of lightning protection. You want to consider a few more venues in this pursuit.......not just your antennas. This will give you some important good pointers (and it does address antennas too.)

http://lightningsafety.com/nlsi_lhm/IEEE_Guide.pdf
.
Cheers
.
..........................CF
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Old 06-08-2017, 8:55 PM
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mmckenna said:
Quote:
Do NOT ground your antenna to your electrical outlet grounds.
...but this is quite difficult. Any mains powered receiver will have a 3-conductor power lead with the ground lead connected to the chassis - even if it's only through the negative lead of an external power supply. If the incoming antenna lead is through the normal BNC or SO239 socket mounted to the chassis, then you have joined the power ground to your antenna ground. I note that your regs say that you must bond all grounds together to comply and shield yourselves from the wrath of the electrical inspectors and the insurance company if (God forbid) you do get a lightning strike. Here, being long narrow islands with a notably damp atmosphere, lightning strikes are few and far between thank goodness and I'm certainly not the highest antenna around!
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Old 06-08-2017, 10:22 PM
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Quote:
Originally Posted by majoco View Post
Any mains powered receiver will have a 3-conductor power lead with the ground lead connected to the chassis - even if it's only through the negative lead of an external power supply. If the incoming antenna lead is through the normal BNC or SO239 socket mounted to the chassis, then you have joined the power ground to your antenna ground.
You're barking up the wrong tree here. The ground rods for the antenna tower and utility power should be directly connected by the shortest possible run of 6-gauge or larger wire, rather than relying solely on a long loop between the antenna coax shield and the ground conductor in the houshold wiring. It's fine if there is a secondary connection between grounds through the household wiring, but the primary connection must be a direct run of heavy wire between all ground rods.
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Old 06-09-2017, 12:21 PM
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A cautionary note... all Grounds are not created equal.
.
When dealing with lightning, a factor called the Ground Potential Voltage Rise raises its ugly head, This is the unequal voltage distribution along wires that occurs during the microsecond's discharge of millions of volts into an electrical system.... and it will seek its earth connection thru everything and anything it finds, and at disproportional voltages.
.
This unequal voltage distribution in those microseconds of discharge causes tremendous damage.... and the chief culprits are a lot of multiple grounds.
.
In our remote field stations, repeaters and such-- everything in those huts goes thru one, and only one, grounding port; all the AC power spike, telephone/data lines, antenna bulkhead arrestors.. and all the equipment grounds, tie into this, and only this--one heavy copper plate. The towers are another story, but all the electronics in the huts 'float' on that single ground- no secondary paths are created to the earth.
.
And these installations get hit a LOT !...
.
In ham radio Lightning suppression, like Antennas- is full of advice. Be chary in how you partake of it
.
.
.....................CF
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Old 06-09-2017, 1:56 PM
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Quote:
Originally Posted by Coyote-Frostbyte View Post
A cautionary note... all Grounds are not created equal.
.
When dealing with lightning, a factor called the Ground Potential Voltage Rise raises its ugly head, This is the unequal voltage distribution along wires that occurs during the microsecond's discharge of millions of volts into an electrical system.... and it will seek its earth connection thru everything and anything it finds, and at disproportional voltages.
.
This unequal voltage distribution in those microseconds of discharge causes tremendous damage.... and the chief culprits are a lot of multiple grounds.
.
In our remote field stations, repeaters and such-- everything in those huts goes thru one, and only one, grounding port; all the AC power spike, telephone/data lines, antenna bulkhead arrestors.. and all the equipment grounds, tie into this, and only this--one heavy copper plate. The towers are another story, but all the electronics in the huts 'float' on that single ground- no secondary paths are created to the earth.
.
And these installations get hit a LOT !...
.
In ham radio Lightning suppression, like Antennas- is full of advice. Be chary in how you partake of it
.
.
.....................CF
now you are scaring me
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Old 06-09-2017, 3:52 PM
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Hey jonwienke, I understand your regs, that's why I said...

Quote:
I note that your regs say that you must bond all grounds together to comply and shield yourselves from the wrath of the electrical inspectors and the insurance company if (God forbid) you do get a lightning strike.
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Old 06-09-2017, 4:27 PM
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(Laughing ) I'm sorry if all this is a bit scary, Xccess... but when you come down to it, lightning is a pretty scary subject.
.
I have been on mountain tops and been almost hit several times.
.
Here's a favorite story... ... of being at a high altitude meteorological research station- designed to with stand just such direct lightning hits-- and Oh-Boy did I experience lightning first hand!... Multiple hits during multiple storms over several days. St. Elmo's Fire is beautiful, but not when it encircles you earrings and bracelets!
.
... One of the things that strikes visitors to this station are the tall stools mounted on telephone pole glass insulators. Think you're tough?.. ... try not to cluster with everyone else in the centre of the station, perch'd on your stool, as Zesus shows off what he can hurdle... The station has a protective 'sacrifical mast'-- actually the mother-of-all lightning rods-- some 75 feet tall next to the building. That savior took all the hits- and a good thing it did, too.
.
Another....
.
Not long ago I visited a site where the awesomeness of lightning demonstrated its capricious nature. This site had withstood years and countless electrical storms on an Arizona mountainside. But the gods were in a mischievous mood one storm, and show'd us Who was Who. A thick 2 inch (!) copper strap ran from the common grounding block (describe in my last post) down the inside of the equipment hut, and thru the cinderblock wall. It went another 2 feet or so to where it bolted to the 3x3" metal tie point of an extensive copper ground matrix.
.
Well, that individualistic piece of lightning, not wanting to behave like its kith and kin, took a short cut half way down that strap, blasting an 18" hole thru the cinderblock wall and arced over to,-- not that ground post,-- but a large propane tank used to power the back up generator. It blew the paint off half that huge tank and fused all the bolts solid that held the tank to its concrete foundation. Fortunately it didn't blow up the tank!....
... and all the electronics?-- they survived as if this was an entirely harmless, normal thing for lightning to do-- for our entertainment, mind you.
.
Xccess, if I have resorted to being anecdotal, its because I see this stuff in the very colourful light-- and here as in first hand experience. Being a little bit scared?? Nothing wrong with that. Do your research, and follow a scientific approach to this little issue ( ) and you will be fine....
.
Oh, that..., and maybe don't taunt the gods with an antenna too pretentious.....
.
.
....................................CF

Last edited by Coyote-Frostbyte; 06-09-2017 at 4:37 PM..
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Old 06-09-2017, 10:22 PM
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Quote:
Originally Posted by Coyote-Frostbyte View Post
(Laughing ) I'm sorry if all this is a bit scary, Xccess... but when you come down to it, lightning is a pretty scary subject.
.
I have been on mountain tops and been almost hit several times.
.
Here's a favorite story... ... of being at a high altitude meteorological research station- designed to with stand just such direct lightning hits-- and Oh-Boy did I experience lightning first hand!... Multiple hits during multiple storms over several days. St. Elmo's Fire is beautiful, but not when it encircles you earrings and bracelets!
.
... One of the things that strikes visitors to this station are the tall stools mounted on telephone pole glass insulators. Think you're tough?.. ... try not to cluster with everyone else in the centre of the station, perch'd on your stool, as Zesus shows off what he can hurdle... The station has a protective 'sacrifical mast'-- actually the mother-of-all lightning rods-- some 75 feet tall next to the building. That savior took all the hits- and a good thing it did, too.
.
Another....
.
Not long ago I visited a site where the awesomeness of lightning demonstrated its capricious nature. This site had withstood years and countless electrical storms on an Arizona mountainside. But the gods were in a mischievous mood one storm, and show'd us Who was Who. A thick 2 inch (!) copper strap ran from the common grounding block (describe in my last post) down the inside of the equipment hut, and thru the cinderblock wall. It went another 2 feet or so to where it bolted to the 3x3" metal tie point of an extensive copper ground matrix.
.
Well, that individualistic piece of lightning, not wanting to behave like its kith and kin, took a short cut half way down that strap, blasting an 18" hole thru the cinderblock wall and arced over to,-- not that ground post,-- but a large propane tank used to power the back up generator. It blew the paint off half that huge tank and fused all the bolts solid that held the tank to its concrete foundation. Fortunately it didn't blow up the tank!....
... and all the electronics?-- they survived as if this was an entirely harmless, normal thing for lightning to do-- for our entertainment, mind you.
.
Xccess, if I have resorted to being anecdotal, its because I see this stuff in the very colourful light-- and here as in first hand experience. Being a little bit scared?? Nothing wrong with that. Do your research, and follow a scientific approach to this little issue ( ) and you will be fine....
.
Oh, that..., and maybe don't taunt the gods with an antenna too pretentious.....
.
.
....................................CF
ok now you are even scaring me more .. time to take this antenna off and forget about this hobbies
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Old 06-10-2017, 7:27 AM
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Thousands of amateur radio operators have antennas up at their houses. Most of them are pretty loose with their grounding. Most of them never get a lightning hit.

Are they playing with fire? Are they lucky? Are they benefiting from the fact that lightning is a somewhat random occurrence? Yes to all three.

I'm not advocating that you ignore good grounding practices. But, I am pointing out that the likelihood of you having a problem with lightning is small.
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Old 06-10-2017, 1:03 PM
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Oh, com'on Xccess, don't let this little lightning thingy dissuade you --at least not yet. There are far more worrisome esoterics in radio to worry about..... like the the four foot rattlesnake last week-- curled up, inside a hut, warmly sleeping beneath a transformer pile. We didn't see it for over an hour; us two little innocents tinkering away. Then it finally awoke and started rattling, right at my feet--- scared the #!@!& out of us.
A rather graphic example-- but: You are far far more likely to be bitten by a snake than to suffer a lightning strike.... however, don't look to my personal record on this- I seem to be moving ahead of the curve here... (laughing)
.
If you look at all the stats, a direct hit is *very* rare. Yet this is what everyone fears.,,, and what I can't, so colourfully-- keep from describing. If one of those Bolts has your name on it, that's just Fate and there is not much you can do about it- and I don't care if you are Average Joe Ham or one of our engineers- its going to be BAD and that's that.
.
But its not the direct hits you should be concern'd about. Practically all the damage everyone worries about will come in the form of secondary spikes-- those little buggers that will find there way into your setting- from a powerline struck, to maybe a tree nearby-- All these strikes can induce tremendous microsecond pulses into your house wiring and damage your sensitive electronics.... and sometimes that spike doesn't have to be much... a few hundred volts will fry your microwave oven..... Hence the surge protectors, antenna 'lightning arrestors'...et al., they are your first line of defense against 99% of these threats**
.
So install them- but do it properly. Disconnect your antenna when not in use- unplug your radio during electrical storms-- follow all the myriad of simple lightning safety tips that abound everywhere... and you will be Okay.
.
If you want to start spinning off into madness, start with the the AC service line into your house. Is it a drop line or is it underground?.... think it makes a diffference?..Ha! Its just another 'antenna'--coming right into your home.
What have you in the way of a whole house powerline surge protector? (I dare say few of you out there have one..... I don't.)
.
Do you have any any lightning rods install on your house? a'la Ben Franklin? .. are they installed properly?... bet I know the answer (I do, by the way, have them on my home in the mountains- but I live in Lightning Alley.)
.
My point is, if you are going to take this lightning threat to heart, look at the whole subject- not just your antenna. Chances are Zip that anything you install as a ham (short of that 100 foot tower ) will be of any more danger to you than your nearby powerlines.
.
What I do professionally and what I do a Lauri Average, unfortunately is quite different. I too, get complacent. I will say in my defense that I adhere to the 'Floating Ground" school in my home-- all my electronics connect to one and only one common ground point- My earth connection encircles my house as a single 1/2" braided copper cable, with deep ground rods at frequent intervals-- this was designed and installed by professionals- this 'circle of copper' also is the tie-ins for the 'air terminals' (neat term, No?) for the lightning rods.
.
Xccess, put your antenna up- do your own research, keep the Scientific Method before you always- in your Lightning protection, in working around any voltages--- You do keep your other hand in your pocket when adjusting live HV circuits don't you?..smiles
.
(laughing) There, that's one more thing to worry about- and for me HV is far far more worrisome than lightning
..........................except maybe Rattle Snakes
.
..............................CF
.
.
.
.
.
.
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**99% is just a number for illustrative purposes- it may not be that high, but my unscientific confidence places it around that figure
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Old 06-10-2017, 4:54 PM
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CF said:
Quote:
I see this stuff in the very colourful light
No pun intended?

......and 'colourful' spelt correctly?

I have been in an aircraft getting a strike a couple of times - the second time the whole cabin stayed ionised for a few seconds with St. Elmo - weird light-headed 'out of body' experience - fortunately no damage to any of my equipment or the flight deck gear. Punched a 1/8" neat hole just above the cockpit window - never found the exit one, perhaps the static wicks bled the charge away rather than continuing the strike.
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Old 06-10-2017, 11:11 PM
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Quote:
Originally Posted by Coyote-Frostbyte View Post
Oh, com'on Xccess, don't let this little lightning thingy dissuade you --at least not yet. There are far more worrisome esoterics in radio to worry about..... like the the four foot rattlesnake last week-- curled up, inside a hut, warmly sleeping beneath a transformer pile. We didn't see it for over an hour; us two little innocents tinkering away. Then it finally awoke and started rattling, right at my feet--- scared the #!@!& out of us.
A rather graphic example-- but: You are far far more likely to be bitten by a snake than to suffer a lightning strike.... however, don't look to my personal record on this- I seem to be moving ahead of the curve here... (laughing)
..
Xccess, put your antenna up- do your own research, keep the Scientific Method before you always- in your Lightning protection, in working around any voltages--- You do keep your other hand in your pocket when adjusting live HV circuits don't you?..smiles
.
(laughing) There, that's one more thing to worry about- and for me HV is far far more worrisome than lightning
..........................except maybe Rattle Snakes
.
..............................CF
.
.
Now I am even more terrify , but to be honest, I want to do it right as much as I can, however, you are right if sh*t hit the fan nothing can stop it with nature. I start out as just two small two-way radio, but somehow I found my way to set up repeater for GMRS and talking to local radio shop here as well about using their antenna for relay. I am just bit of disappointing with my repeater signal now.. I get about 5-7 miles from my repeater with the handheld. my attenna is about 10 feet up in the air from the root.... how the heck did ham people people get they signal out at 100s miles away? I realized the higher the antenna go the better signal. look like I will need to rent space from NASA up in the sky to put my antenna up there

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CF said:


No pun intended?

......and 'colourful' spelt correctly?
I believed in some country does spell it that way
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Old 06-11-2017, 4:12 AM
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Quote:
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.... how the heck did ham people people get they signal out at 100s miles away?
The answer to that question is easy.

1. They aren't using a repeater with an antenna only 50 feet in the air. They are using repeaters which have antennas that are 100s of feet in the air and/or those repeaters are linked together to extend the range of the system.

2. They aren't using 5 watt handhelds. You can get UHF mobile radios for amateur radio that put out 50 watts and you can get amplifiers to go beyond that. An amateur radio license in the U.S. permits you to use as much as 1500 watts.

3. They aren't using UHF. I have an antenna in my back yard that is about 16 feet of the ground and I can use it to talk 100s of miles. I have another antenna that's mounted at the ground and I can use it to talk 1000s of miles. In both cases, I'm using those antennas on the amateur radio HF bands, not UHF. HF radio waves tend to reflect off of the ionosphere thus extending my range around the world while UHF signals do not typically reflect and are limited to line of sight communications.
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Old 06-11-2017, 8:50 AM
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The answer to that question is easy.

1. They aren't using a repeater with an antenna only 50 feet in the air. They are using repeaters which have antennas that are 100s of feet in the air and/or those repeaters are linked together to extend the range of the system.

2. They aren't using 5 watt handhelds. You can get UHF mobile radios for amateur radio that put out 50 watts and you can get amplifiers to go beyond that. An amateur radio license in the U.S. permits you to use as much as 1500 watts.

3. They aren't using UHF. I have an antenna in my back yard that is about 16 feet of the ground and I can use it to talk 100s of miles. I have another antenna that's mounted at the ground and I can use it to talk 1000s of miles. In both cases, I'm using those antennas on the amateur radio HF bands, not UHF. HF radio waves tend to reflect off of the ionosphere thus extending my range around the world while UHF signals do not typically reflect and are limited to line of sight communications.
Thanks for explaining it. I am in the process study to get me a HAM license .. this is going to be fun
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Old 06-11-2017, 9:53 AM
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The answer to that question is easy.
You forgot 4.
He could have been hearing a RoIP node that was nearby but the people talking at the time could be anywhere.
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Old 06-14-2017, 5:30 PM
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Don't overlook the fact that a direct lightning strike is the only risk. Even nearby ones can induce enough energy into the antenna, mast, coax, etc. to cause issues.

A long time ago we had a lightning strike at work. Not sure exactly where it hit, but an improperly installed and grounded underground copper telephone cable took a lot of energy. It blew out an old terminal server system (this was quite a while ago) a mile or two away.

Thanks to the numbskulls that decided that grounding was "optional" and played fast and loose with the NEC as well as common sense, we saved a few bucks on install, but paid a lot more for damaged equipment.

I was on a ship once that was hit by lightning. It didn't take out the HF radio, radar, VHF or any of the "other" stuff. What it did take out was one of the engine management computers all the way down in the engine room.

Lightning will not play by your rules. You can attempt to direct it's flow, but it might just laugh at you and go the opposite direction, as CF pointed out.
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Old 06-15-2017, 4:11 PM
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I received a personal message about the discussion (here) on lightning, that got got me thinking about the vagaries in the different types of lightning.... like my account of that errant bolt that decided to take out a piece of the equipment hut rather than follow the ground strap that countless other hits had coursed. Why did it do that?.. to be more precise, what exactly made it decide to do that?
.
Okay, the physics can give some insight- and a technical warning too- to a lightning bolt. They are comprised of some incredibly high radio frequency pulses- and behave according to the same rules employed in RF circuits. In the case of "Cinderblock," we figured the length of the copper strap and its slight drip-loop at its ground tie point formed an efficient RF choke that sent the errant bolt off thru the wall. That's cool- the drip loop is now gone- impedence should have dropped---- let's see if Zesus notices.
.
This recalled to me a project of my friend and work Sidekick, "Barbi." **
She was running a HIPAS (High Power Auroral Stimulation) project using a former military site, far far above the Arctic Circle. The site had been moth-balled for some time and it was with no considerable effort we got things reasonably back in order. The heart of this installation- or at least the part we were interested in, was the high power'd Blow Torch of a HF transmitter and its curtain array antenna.
When the transmitter was brought back to life, at a greatly reduced power output, that antenna was not taking the load correctly. All the parameters were off, and it would have been a disaster to continue the project at high power until it was corrected. The most likely cause, consensus had it, was a corroded/weather'd connection(s) somewhere in that antenna array. But where?
Barbi came up up with a novel diagnotic.. at night, the transmitter on, we'd look for arc's at the myriad bolt'd joints in the array.
.
But... it was like looking for needles in a hay stack ..................... (hang in there, the lightning part is coming up.... )
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Then another bright idea. Modulate the signal and Listen for the arc's. So we readjusted the bias on the PA from a Class C to AB1, and feed Barbi's stream of a Blondie CD into the driver as AM. We figured that a few hours of Debbie Harry was better than a warbling tone or some such.. we don't ID, and never think of asking for SWL reports.
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Next night- the setting. It was like 50 below- crystal clear sky- the Aurora streaming from horizon to horizon.....
"the Northern Lights were running wild in that Land of the Midnight Sun...." (..........Robert Service.) And so was the transmitter.
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And outside you could here music!
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Barbi, in her parka, boots and gloves- went out to locate the arc's. She was gone but a few minutes when she came bursting back into the building:
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"Lauri !, Guys!... come quick, you won't believe this !.... C'est un feu d'ange !"
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(she's French...this happens often when excited ) ...
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"Angel Fire?.. what are you talking about?"
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"Come out side. Quickly, Run!!.......Ahh, its Ball Lightning! ... its dancing on the curtain !"
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By the time we made it out the door into that bitter cold (I wasn't wearing a coat or gloves)-- it was gone. But Debbie was still singing in the wires.
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"It was right there!" said Barbi, pointing to the array,
"It was about 2 feet in diameter, a bright blue ball of light!... it float'd to the ground over there.." (pointing to a tower base.)
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"And that's when I came and got you"
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Well. there was nothing to see and I was rapidly freezing. Coyote Frostbyte for real.
_______________

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Back inside, a little skepticism was in the air.. not on my part, mind you (smiling).. but I couldn't help but ask my friend:
"Where is the bottle of Vodka?.... this wasn't...... Oh, never mind"
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___________________________________
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But the next morning, at the base of the tower was a hole melted thru the snow down to the earth- a perfect 2 foot diameter circle.
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If a French physicist says she sees Angel Fire- believe her.
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___________________________________________
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Was it Ball Lightning?,, where did it come from? There aren't storms like that there in the dead of winter.....
I have seen St. Elmo's fire several times, but never Ball Lightning............. Maybe I really don't want to!-- but have any of you had such and experience, ever seen
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................ un feu d'ange ?

.
.
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.................................................. .CF
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Story told while sitting in an airport- this connecting flight lay-over stuff is time best turn'd to stories...
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__________________________________________________ ______________
**Her nickname, I'll leave it to the imagination why- its her work radio callsign too- Barbi is a PhD., particle physicist.

Last edited by Coyote-Frostbyte; 06-15-2017 at 4:29 PM..
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