Need a simple lightning protector setup

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dragon48

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My hurricane proof apartment is mostly an RF dead zone, but if I step out on my balcony with a radio, reception is fine. The problem is that rainy season is starting now, and I don't want to risk damaging my equipment from a lightning strike.

I just want to drag a 13-inch metallic antenna outside. I don't want to throw a lot of money at the solution but need to be safe. My main project is picking up ISS SSTV next week at 145.800 MHz and I don't want to put anything in between the antenna and the radio that would interfere with reception.

What is recommended?

Also, just curious how much damage a direct, or nearby lightning strike could cause? I'm going to have a 3.5 mm audio cable going from the radio to a USB sound card connected to a powered USB hub connected to my laptop. Could a lightning strike break the radio, fry my laptop, and damage other equipment connected to the hub?
 

k7ng

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A good lightning protector won't attenuate the signals even enough to measure.
I have used the Alpha Delta products: https://www.alphadeltaradio.com/pg3-surge.html
I don't have any pecuniary interest in that company, I just have used their products before.

Beyond a decent lightning protector, the next step to good lightning protection is the best possible earth ground and having everything connected to a common ground point. You being in Florida, you do have a much more severe problem than I. The best you can do for a non-permanent antenna installation is to not give the lightning anything to strike. In your case as described, bringing your antenna inside when you aren't using it and disconnecting it from the equipment is a fine means of protection.

A lightning strike won't necessarily stop at the radio. It goes anywhere it can. It can come in on the utility power too.

You can't be too safe. I disconnect everything, unplug it all, and be somewhere else in the house if there is known lightning around. Generally when I'm not using the equipment the antenna cables are switched to ground (and have lightning protection as well).

Others may have inputs as well, but the above may be a start.
 

iMONITOR

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My hurricane proof apartment is mostly an RF dead zone, but if I step out on my balcony with a radio, reception is fine. The problem is that rainy season is starting now, and I don't want to risk damaging my equipment from a lightning strike.

I just want to drag a 13-inch metallic antenna outside. I don't want to throw a lot of money at the solution but need to be safe. My main project is picking up ISS SSTV next week at 145.800 MHz and I don't want to put anything in between the antenna and the radio that would interfere with reception.

What is recommended?

Also, just curious how much damage a direct, or nearby lightning strike could cause? I'm going to have a 3.5 mm audio cable going from the radio to a USB sound card connected to a powered USB hub connected to my laptop. Could a lightning strike break the radio, fry my laptop, and damage other equipment connected to the hub?

There is no such thing as a "simple lightning protection setup". Nothing will protect your equipment from a direct lightning strike. It could burned down your entire apartment building. You be very limited as to what you can do anyway in an apartment building.
 

prcguy

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Just be advised that within a reasonable budget, you cannot prevent damage from a direct lightning hit. Since your antenna is very small its unlikely to pick up much EMP from a nearby strike so in my opinion the best you can do is simply ground the antenna per National Electrical Code. Here is some info on the subject and you can find more by searching "NEC Article 810".
 

iMONITOR

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Just be advised that within a reasonable budget, you cannot prevent damage from a direct lightning hit. Since your antenna is very small its unlikely to pick up much EMP from a nearby strike so in my opinion the best you can do is simply ground the antenna per National Electrical Code. Here is some info on the subject and you can find more by searching "NEC Article 810".

How would he accomplish this in an apartment building that most likely doesn't allow outdoor antenna to begin with?
 

dragon48

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A good lightning protector won't attenuate the signals even enough to measure.
I have used the Alpha Delta products: https://www.alphadeltaradio.com/pg3-surge.html
I don't have any pecuniary interest in that company, I just have used their products before.

Beyond a decent lightning protector, the next step to good lightning protection is the best possible earth ground and having everything connected to a common ground point. You being in Florida, you do have a much more severe problem than I. The best you can do for a non-permanent antenna installation is to not give the lightning anything to strike. In your case as described, bringing your antenna inside when you aren't using it and disconnecting it from the equipment is a fine means of protection.

A lightning strike won't necessarily stop at the radio. It goes anywhere it can. It can come in on the utility power too.

You can't be too safe. I disconnect everything, unplug it all, and be somewhere else in the house if there is known lightning around. Generally when I'm not using the equipment the antenna cables are switched to ground (and have lightning protection as well).

Others may have inputs as well, but the above may be a start.

Thanks,

I'll take a look at the linked products. Not sure if it is the geography or building geometry, but my building and the parking lot attached to it get hit by lightning a lot! Earlier in the week while I was driving, a strike came very close to hitting my car. I'll probably just be safe and take the antenna inside when it rains with the possibility of lightning, which pretty soon is every day after 1:00 P.M. :)
 

prcguy

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Even though NEC requires all outdoor antennas be grounded to a certain specification there may not be any legal ground points within reach of a balcony mounted antenna or coax. If the balcony is not on a top floor then I would not bother with a ground. If its a top floor and if you have a mast that pushes the antenna up near or above roof level that's a different story but you would still need a legal ground like metallic conduit or water/sprinkler pipe, etc. Is there a metal railing around the balcony? If so it could be bonded to the building ground and you could test for that with an ohmmeter. Are there any electrical outlets on the balcony? You could make up a 3 prong power plug with a ground wire and attach that to the antenna or coax. It would be a safety ground but not a legal one.

How would he accomplish this in an apartment building that most likely doesn't allow outdoor antenna to begin with?
 

dragon48

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Even though NEC requires all outdoor antennas be grounded to a certain specification there may not be any legal ground points within reach of a balcony mounted antenna or coax. If the balcony is not on a top floor then I would not bother with a ground. If its a top floor and if you have a mast that pushes the antenna up near or above roof level that's a different story but you would still need a legal ground like metallic conduit or water/sprinkler pipe, etc. Is there a metal railing around the balcony? If so it could be bonded to the building ground and you could test for that with an ohmmeter. Are there any electrical outlets on the balcony? You could make up a 3 prong power plug with a ground wire and attach that to the antenna or coax. It would be a safety ground but not a legal one.

There is a metal railing around the balcony. What setting on my multimeter would I use to test whether it's bonded to the building ground?
 

prcguy

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Use the lowest ohm scale and check between the railing and the third grounded prong on an AC outlet. I would hope its less than a few ohms if the railing is bonded to building ground.

There is a metal railing around the balcony. What setting on my multimeter would I use to test whether it's bonded to the building ground?
 
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