Do they make an inline Lightning arrester (bnc to bnc) ? I want something that plugs directly into the back of my BCT 8.
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Lightning arrester ?
- Thread starter fireman_dude
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N_Jay
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You want to put the lightening arester where the cable enters the house, not right on the back of the equipment.
N_Jay is correct, the lightning arrestor, stays outside (you don't want lightning inside 
). As for the connections, I have never seen a BNC type, since they are designed to be outside. Most good ones use "N" connectors with some using UHF (SO-239).
). As for the connections, I have never seen a BNC type, since they are designed to be outside. Most good ones use "N" connectors with some using UHF (SO-239).
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N_Jay
Guest
loumaag said:N_Jay is correct, the lightning arrestor, stays outside (you don't want lightning inside
CATV ones use F connectors (and are usually cheap crap)
Hi all,
The NEC requires the coax shield to be grounded where it enters the house, that's all the cable company does. Those "lighning arrestors" are simply a dual female F connector pressed into a mounting bracket with a hole and set screw to attatch the earthing wire. Then those buggers usually connect it to the metal conduit that brings the electrical service into the house and rely on the service panel ground usually connected to the water main. Lovely, iddnit?
The proper grounding may be accomplished by simply connecting the SHORT earthing wire to a double SO-239 and screwing the PL-259s on each end. Bring the coax near to the ground and back up again if need be. Wrap the connection tightly with vinyl electrical tape for waterproofing and there you have it, instant lightning arrestor.
Need I tell you to leave the coax unplugged unless you're actually using the scanner and never during a lightning storm? Yeah, lightning has a nasty habit of showing up at unexpected times, even during a winter snowstorm, I have seen some doozies.
The NEC requires the coax shield to be grounded where it enters the house, that's all the cable company does. Those "lighning arrestors" are simply a dual female F connector pressed into a mounting bracket with a hole and set screw to attatch the earthing wire. Then those buggers usually connect it to the metal conduit that brings the electrical service into the house and rely on the service panel ground usually connected to the water main. Lovely, iddnit?
The proper grounding may be accomplished by simply connecting the SHORT earthing wire to a double SO-239 and screwing the PL-259s on each end. Bring the coax near to the ground and back up again if need be. Wrap the connection tightly with vinyl electrical tape for waterproofing and there you have it, instant lightning arrestor.
Need I tell you to leave the coax unplugged unless you're actually using the scanner and never during a lightning storm? Yeah, lightning has a nasty habit of showing up at unexpected times, even during a winter snowstorm, I have seen some doozies.
MacombMonitor
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None of these devices are going to stop lightning from entering your house, even if the device is mounted outside. They simply bleed off electrostatc charges that build on on the antenna, and coax, during electrical storms. If your antenna takes a hit, so will your radio, and probably a portion of your house as well. :shock:
bsavery
Member
Good timing on this.... I actually had an antenna hit last night.
It was a fiberglass Omni directional antenna on a 10' mast on top of a 10 story building.
The repeater kept running for several hours after the storm before it finally decided the SWR was too high and shut down.
The antenna is missing the top 6-8 inches, and the shiney silver case of the lightening protector is now a nice black and bronzish color.
Replaced both, reset the repeater, and we were back up and running.
GOOD lightening protectors can and do work. No need to unplug anything. So called protectors that just gound the outside of the shield though don't work and should never be trusted! All they do is ensure the bolt travels through the house before going to ground.
Expect to pay a pretty penny for them though! I'm not sure what this one cost, but I'm sure it was expensive!
Bob
It was a fiberglass Omni directional antenna on a 10' mast on top of a 10 story building.
The repeater kept running for several hours after the storm before it finally decided the SWR was too high and shut down.
The antenna is missing the top 6-8 inches, and the shiney silver case of the lightening protector is now a nice black and bronzish color.
Replaced both, reset the repeater, and we were back up and running.
GOOD lightening protectors can and do work. No need to unplug anything. So called protectors that just gound the outside of the shield though don't work and should never be trusted! All they do is ensure the bolt travels through the house before going to ground.
Expect to pay a pretty penny for them though! I'm not sure what this one cost, but I'm sure it was expensive!
Bob
Al42
Member
Tell that to WRRC - they lost a tower many years ago due to a main stroke hit, in spite of a very good "protection" system (which vaporized along with the tower). You were probably hit by a feeder, or induction from a main stroke.bsavery said:
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N_Jay
Guest
Al42 said:
I have seem many a tower (With proper protection) take a direct strike with no damage.
The trick is proper protection, and a bit of luck.
The better the protection the more bad luck you can withstand. :twisted: :wink:
If the lightenting "vaporized" a tower, then something was VERY wrong.
Like an old tower with rusty joints and little grouinding!
MacombMonitor
Member
- Joined
- May 18, 2005
- Messages
- 3,551
Here are a couple sources for these protective devices:
http://www.grove-ent.com/LAR1F.html
http://www.universal-radio.com/catalog/protect.html
http://www.grove-ent.com/LAR1F.html
http://www.universal-radio.com/catalog/protect.html
Al42
Member
Mounted into a few tons of keystoned concrete. An 18" diameter steel ball was welded to the tower. Another 18" ball was mounted on what amounted to a piece of tower leg driven about 20 feet into the ground, connected to a ground field that took up about an acre. The gap was about 4" (small enough that 100% modulation didn't cause an arc on a rainy day, plus 1"). This was designed and installed by a commercial tower company.N_Jay said:
But, as you said, enough bad luck can overcome good design.
Bottom line, for me, at least, is to never assume that anything I install is "protected" against lightning. It's a lot cheaper to replace a worn-out connector than to replace even a cheap radio - and a house, if my luck runs out.
Al42
Member
Aircraft Radio Corp. used the same thing on ARC-5 receivers (back when we had dinosaurs for pets, kiddies). They put an NE-2 neon bulb from the antenna terminal to ground.MacombMonitor said:
Hi all,
"None of these devices are going to stop lightning from entering your house, even if the device is mounted outside. They simply bleed off electrostatc charges that build on on the antenna, and coax, during electrical storms. If your antenna takes a hit, so will your radio, and probably a portion of your house as well."
You can tell that to my grandmother whose TV antenna was struck. We replaced the antenna, downlead and lightning arrestor, the set was untouched.
That proved to me at least that proper lightning arrestors and proper installations DO work but it's NO GUARANTEE that everything won't go up in flames. A properly installed earthing system for coax as I described in my previous post is in accordance with NEC/NFPA regulations so that should tell you it DOES work.
As for leaving the coax disconnected when not in use, that eliminates an alternate path to ground through the equipment. Of course that can't be done in the case of the repeater that was mentioned, but it can save you a fried rig at home. I have seen lightning do some strange and unexplainable things so like I said there's no guarantee, but still proper precautions make you better safe than sorry.
OK, go on with your endless debate of the unknown and unpredictable, it's not the first I've seen and surely won't be the last. (;->)
"None of these devices are going to stop lightning from entering your house, even if the device is mounted outside. They simply bleed off electrostatc charges that build on on the antenna, and coax, during electrical storms. If your antenna takes a hit, so will your radio, and probably a portion of your house as well."
You can tell that to my grandmother whose TV antenna was struck. We replaced the antenna, downlead and lightning arrestor, the set was untouched.
That proved to me at least that proper lightning arrestors and proper installations DO work but it's NO GUARANTEE that everything won't go up in flames. A properly installed earthing system for coax as I described in my previous post is in accordance with NEC/NFPA regulations so that should tell you it DOES work.
As for leaving the coax disconnected when not in use, that eliminates an alternate path to ground through the equipment. Of course that can't be done in the case of the repeater that was mentioned, but it can save you a fried rig at home. I have seen lightning do some strange and unexplainable things so like I said there's no guarantee, but still proper precautions make you better safe than sorry.
OK, go on with your endless debate of the unknown and unpredictable, it's not the first I've seen and surely won't be the last. (;->)
N
nmfire10
Guest
Guys, there are many many levels of "getting hit by lightning". There is a huge difference between the main stroke finding your antenna, and some other less violent phenomenon of lightning hitting it. You guys that are saying you "got hit by lighting" and your radio shack static discharge block saved your house probably didn't get a "real" direct hit.
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