that happens quite frequently at my station at home and I have had no damage
from it... of course all antenna lines now have bandpass filters and stubs and
grounding switches so that voltage should never get to the amps or radios, but
it does happen at the inputs to the tuners for the 80m inverted V at 150' which
is before the stubs and switches.
Apr 20, 2015 09:48:48 AM, patrick_g@windstream.net wrote:
David, I had that same tick, tick, tick from my marine band VHF with
masthead antenna. At first I thought it was my knotmeter's log but the
tick rate got way too fast for our boat speed. I went hunting for the
sound and it was arcing at the chassis mount UHF connector, I took my
chances, unplugged the antenna, put a jumper across the PL-259 and stuck
the coax down by the propshaft to offer a safe path for any lightning.
Nothing happened, no damage to the radio, no lightning was evident at
all then or for the rest of the day. Later in port (Catalina Harbor on
the west side of the isthmus on Santa Catalina Island) I gingerly
checked things out and returned the antenna to the radio which still
worked fine.
If two of us had this happen then it is likely not especially rare
although you are the only other person to volunteer this experience to
my knowledge.
Patrick NJ5G
On 4/20/2015 6:30 AM, David Robbins wrote:
> I had to replace the front end protection diodes in a cb once. I started
> hearing this tick-tick-tick sound from the radio, the receiver went dead,
> then there was a lightning flash a mile or two away. then it started ticking
> again until the next flash. I pulled the antenna line off the radio and it
> was arcing across inside the pl-259. this was out on a high dry plane out
> west, I don't think the storm ever got rain to the ground but it sure made an
> impressive lightning show.
>
>
> Apr 19, 2015 10:15:54 PM, patrick_g@windstream.net wrote:
>
> Bill, in so doing you would be just as wrong as Hans. Re the CB
> comment. To my knowledge we never replaced a CB for lighting causes.
>
> Patrick NJ5G
>
> On 4/19/2015 7:33 PM, Bill Aycock wrote:
>> Hans is right, if a little too gentle. I would have called the tale
>> "manufactured" on "Invented" rather than "Anecdotal".
>> Bill--W4BSG
>>
>> -----Original Message----- From: Hans Hammarquist via TowerTalk
>> Sent: Sunday, April 19, 2015 2:44 PM
>> To: towertalk@contesting.com
>> Subject: [TowerTalk] Fwd: Near Field Lightning Damage
>>
>> This sounds very anecdotal. Yes, a near strike lightning may take out
>> CB radios etc but that it took out digital watches make me suspicious.
>> The are usually metal encapsulated and very immune to external field.
>> I believe a EMP strong enough to take out a watch also will take out
>> the person carrying that watch.
>>
>>
>> Depending on the grid size, a Faraday cage is useful for the EM from a
>> lightning as the "M" will introduce back EMF in the cage which will
>> neutralize the "M".
>>
>>
>> I hope the "falme" will not be too long,
>>
>>
>> Hans - N2JFS
>>
>>
>>
>> -----Original Message-----
>> From: Patrick Greenlee
>> To: towertalk
>> Sent: Sat, Apr 18, 2015 10:18 pm
>> Subject: Re: [TowerTalk] Near Field Lightning Damage
>>
>>
>> Back in the 80's a tuna boat pulled into San Diego with every device on
>> board
>> containing a semi-conductor inoperative. CB radio, Marine VHF,
>> SSB, SONAR,
>> RADAR, VHS tape player, SatNav LORAN, and on and on... All
>> the crew members
>> wore digital watches which were all totally dead.
>>
>> One near miss by a large
>> lightning stroke took out everything with solid
>> state semiconductor junctions.
>> The good news was they didn't have a
>> spotter chopper aloft at the time
>> dependent on the aircraft beacon band
>> transmitter on board to find the boat
>> (helipad is the roof of the pilot
>> house.) We theorized it was the EMP that
>> ate everything as there was no
>> evidence that the bolt hit the boat.
>>
>> Later
>> when asked what could be done to provide an immune backup comm
>> radio we told
>> them a mu metal box. A Faraday cage wouldn't stop the
>> magnetic pulse.
>>
>> Just
>> a thought in case there are any serious preppers in our midst.
>>
>> Patrick
>> NJ5G
>> _______________________________________________
>>
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