On 5/15/2011 6:37 PM, Stan Labinsky Jr. wrote:
> 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.
Earlier I told of the lightning striking the power pole from my neighbor
and myself. That storm was on the order of 10 miles from us.
Also, quite a few years back, my plane was at the FBO's at Houghton
Lake( KHTK ) for maintenance. I was flying a Cherokee 180 up to see how
things were going and a friend who is both a pilot and ham, went with
me. On climb out we could see a lone cumulus of substantial size over
Gladwin (GDW) which was right on our intended flight path. Not wanting
to tangle with thunderstorms we went straight North which would put us
about 12 miles due East of the Storm. As we were passing it, my friend
asked how close I though we could safely get to the storm. Just as he
said that, a bolt of lightning left the cumulus at our level (5,000
feet) and pointed right at us. It curved down and stuck the ground
about 2 miles to the West of us, or abut 10 miles from the storm. Where
it struck was in bright sunshine.
73
Roger (K8RI)
> 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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