If you use an automotive spark plug make sure its not the resistor type.
Carl
KM1H
----- Original Message -----
From: "DAVID CUTHBERT" <telegrapher9@gmail.com>
To: "Bob Kupps" <n6bk@yahoo.com>
Cc: "topband" <topband@contesting.com>
Sent: Friday, July 27, 2012 8:24 AM
Subject: Re: Topband: Fw: Choke Construction Info Needed
>I agree with Tom and Bob that the big, heavy choke is not needed. Even it
> offers too much inductance to be an effective lightning path.
>
> A spark gap is the thing to use across the choke or shorted 90 degree
> feedline. It should have a weather cover and be set close but not too
> close. See ROSS ENGINEERING for a picture of a spark gap. I've use 1/4"
> carriage bolts for spark gaps at 1 kA. I would use a larger one for
> protection against a direct lightning strike. Only 1% of strikes reach 100
> kA but I think that's a good current to design to.
>
> http://www.rossengineeringcorp.com/hv_spark_gap.htm
>
> Dave WX7G
>
>
>
> On Thu, Jul 26, 2012 at 7:53 PM, Bob Kupps <n6bk@yahoo.com> wrote:
>
>> Hi Phil
>>
>> I'm no expert but plan to use a quarter wave shorted stub of RG6 at the
>> feed point of my verticals for static drain and harmonic reduction, along
>> with a spark gap in the event of a close strike.
>>
>> 73 Bob
>>
>> ----- Forwarded Message -----
>> From: Phil Clements <philclements@centurylink.net>
>> To: topband@contesting.com
>> Sent: Friday, July 27, 2012 2:03 AM
>> Subject: Topband: Choke Construction Info Needed
>>
>> I need to construct a heavy-duty choke to be installed from the feed
>> point
>> of my 160 meter vertical to ground, for static drain and for lightning
>> protection. How large does the wire, form, and inductance need to be?
>>
>>
>>
>> Thanks in advance for your expertize!
>>
>>
>>
>> (((73)))
>>
>> Phil, K5PC
>>
>>
>>
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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_______________________________________________
UR RST IS ... ... ..9 QSB QSB - hw? BK
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