Figuring that .045" is a standard 2000V air gap for variable caps in medium
humidity it would be a good place to start. For 1500V set at .030".
Everybody should have a set of feeler gauges(-;
A sacrificial size >100 uH choke should suffice as a static drain and be a
visible indicator of whats happening.
Carl
KM1H
----- Original Message -----
From: <donovanf@starpower.net>
To: "160 reflector" <topband@contesting.com>
Sent: Sunday, July 29, 2012 4:18 PM
Subject: Re: Topband: Spark Gaps..
> Trailer hitch balls should work fine as a lightning arrestor. Typically a
> trailer hitch ball has spherical sides and a flat top. The two balls
> should be oriented so they the spherical surfaces are side-by-side and so
> that rain water and debris cannot bridge them. Ideally they should be
> shielded from rain and insects. The gap should be adjustable, and it
> should be set to about the thickness of a credit card (1 to 2 mm).
>
> 73
> Frank
> W3LPL
>
> ---- Original message ----
>>Date: Sun, 29 Jul 2012 11:33:07 -0600
>>From: DAVID CUTHBERT <telegrapher9@gmail.com>
>>Subject: Re: Topband: Spark Gaps..
>>To: Robert Briggs <vk3zl@bigpond.com>
>>Cc: topband@contesting.com
>>
>>Bob, that an excellent idea!
>>
>>Dave WX7G
>>On Jul 28, 2012 6:06 PM, "Robert Briggs" <vk3zl@bigpond.com> wrote:
>>
>>>
>>> Has anyone thought about using two trailer towing balls set up for a
>>> spark gap? I use this on a 90 foot insulated mast in a very lightning
>>> prone environment....To date "(25)" years, with many direct hits, I have
>>> sustained no damage...Mast is located 20 feet from my lounge room..
>>>
>>> 73..Bob..VK3ZL..
>>> _______________________________________________
>>> 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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