My brother in law back in Iowa a few years ago, put his disconnected coax
ends into a large glass jar. When a tornado passed by about two blocks from
his house, on the ground, he took a direct lightning strike to his 2 meter
FM beam at about 50 feet. The generated electrical envelope build up in the
room popped a diode in his power supply of one of his radios. Everything
was unplugged from the wall and disconnected from the antennas, as I said.
His shack was in the basement and the coast came in the basement window and
over the heat ducting at that point. The lightning had no place to go and
literally arced through the RG8 to the duct work, found a ground outlet in
his furnace and he had to repair the furnace. The best workable situation
is building an outdoor panel made of SO239 female connectors, lightning
arrest those connectors to ground before connecting them to the panel, then
screwing all your antennas to that. Even then, having a coax switch inside
that switches all antennas to ground, once you have disconnected the feed
coax to the radio or tuner or match box, which then goes out to a ground rod
is a lot safer. Who am I to talk. I took a direct lightening strike once
and I was three feet away from the coax switch when it flashed over. I had
two sighted witnesses in the room who saw it, too. My ears rang for an hour
afterward.
Phil.
[log in to unmask]
----- Original Message -----
From: "John Miller" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Saturday, June 20, 2009 7:46 PM
Subject: Re: Lightning Arresters
>a sharp bend in the coax will help too. Doesn't have to be real sharp, but
> about as sharp as you can make around 90 degrees for each type of coax.
> ----- Original Message -----
> From: "Phil Scovell" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Saturday, June 20, 2009 3:14 PM
> Subject: Re: Lightning Arresters
>
>
>> An old broadcast chief engineer told me once to make several turns of the
>> coax in a large three foot loop before putting the coax into the
>> building.
>> It creates a inductor which will theoretically arc the lightning strike
>> off
>> to ground before entering the building due to the resistance.
>>
>> Phil.
>> [log in to unmask]
>>
>>
>> ----- Original Message -----
>> From: "John Miller" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Saturday, June 20, 2009 12:58 PM
>> Subject: Re: Lightning Arresters
>>
>>
>>>A lightning arrester for inside the building? not good at all in my book,
>>> you don't want lightning anywhere near the inside of the building.
>>> ----- Original Message -----
>>> From: "Phil Scovell" <[log in to unmask]>
>>> To: <[log in to unmask]>
>>> Sent: Saturday, June 20, 2009 2:48 PM
>>> Subject: Lightning Arresters
>>>
>>>
>>>>I was asking about lightning arresters based up what I have tried. I
>>>>once
>>>> tried an in-line arrester but discovered, on my R7 multiple band
>>>> vertical,
>>>> it lowered the SWR by about 40 KHz. I couldn't believe it so I tried
>>>> testing it in and out and sure enough, it did change frequencies. No,
>>>> I
>>>> can't remember the model and make of it. I have, for several years,
>>>> been
>>>> using the Alpha Delta gas tube arc-tube coax switch arrester. They
>>>> make
>>>> them for HF and for VHF-UHF operations but they ain't cheap. They are
>>>> really rugged and strong and they make one to mount on a wall, desk, or
>>>> whatever, but they also make one with rubber feet for desk top usage.
>>>>
>>>> Phil.
>>>> [log in to unmask]
>>>
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