There is another aspect that hasn't been mentioned here regarding handling
antenna downfeeders;
Being a member of Sky Warn, I've heard about the possibility, no, the
probability of a lightning strike happening ten or more miles away from a
storm. With no warning, unless you have a dedicated receiver (lightning
detector) running. Taking the chance of doing such a disconnect at the
advent of a storm is... well... just a "little bit" dangerous.
It cannot be predicted and I'd hate to be the friend or relative of the guy
who looses the snap-kaboom lottery.
Stan
----- Original Message -----
From: "Sam Andrews" <sandrews@aristotle.net>
To: "towertalk" <towertalk@contesting.com>
Sent: Sunday, May 15, 2011 12:02 PM
Subject: [TowerTalk] Fw: zapped with my dipole. OUCH!
> The gentleman who began this thread was concerned with eliminating the
> OUCH!
> he got when disconnecting the transmission lines when storms were
> approaching.
> Another question might be "do I really want to leave an open transmission
> line in the shack that might receive a direct or induced lightning
> strike?"
>
> In my case, the answer is NO. I saw one installation that took a big
> induction hit with an open coax on a rig in the kitchen. The strike arced
> from the PL-29 a foot or so to a built-in home intercom system, then to a
> sink faucet on one side, and a central vacuum system outlet on the other.
> Destroyed the intercom and piped vacuum system, and damaged the plumbing.
>
> I have always left my lines connected to the rig. I have taken 4 or 5
> induction hits and the only harm was antenna relays and power supplies
> (easily and inexpensively fixed), as well as some consumer electronics
> devices. Better that than jumping around to other stuff in the home, in
> my
> opinion.
>
> 73, Sam AE5L
>
> ----- Original Message -----
> From: "Grant Saviers" <grants2@pacbell.net>
> To: "K2VI" <k2vi@cox.net>; <towertalk@contesting.com>
> Sent: Saturday, May 14, 2011 7:52 PM
> Subject: Re: [TowerTalk] zapped with my dipole. OUCH!
>
>
>> My I.C.E. coax arrestors measure 680k to ground on the radio side. It
>> seems like a good strategy to bleed off static with a high value
>> non-inductive resistor. 10x that amount (6.8Meg) would handle 2500
>> volts rms in a 2 watt carbon composition rated for the voltage.
>>
>> The antenna side I.C.E. has an toroid inductor to ground, value unkown.
>> In a rare stroke of good luck the unit I measured was open circuit to
>> ground on the antenna side. Inspection showed the center pin of the N
>> connector hadn't been soldered. Now I have to take all of them apart
>> :-( .
>>
>> Grant KZ1W
>>
>> On 5/14/2011 3:59 PM, Jim Lux wrote:
>>> A 1meg resistor to ground?
>>>
>>> On May 14, 2011, at 13:29, "K2VI"<k2vi@cox.net> wrote:
>>>
>>>> It seems every time there's distant lightning and i go to disconnect
>>>> the
>>>> dipole i get this nasty discharge when i touch the pl-259. Im concerned
>>>> it will eventually damage my tuner and or radio. The antenna is not dc
>>>> grounded like my beam or vertical are. It is a ladder line fed antenna
>>>> terminating into a 4:1 balun outside the shack and a 3' run of rg8 coax
>>>> to the tuner. How can i bleed this static off? I heard from a ham
>>>> friend
>>>> the jump a 2.5 MH RF choke between the two terminals of the 4:1 balun
>>>> where the ladder line connects.Any advice would be greatly
>>>> apreciated.73
>>>> tony k2vi
>>>> _______________________________________________
>>>>
>>>>
>>>>
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