Towertalk
[Top] [All Lists]

[TowerTalk] Coax baluns

To: <towertalk@contesting.com>
Subject: [TowerTalk] Coax baluns
From: jreisert@jlc.net (Joe Reisert)
Date: Mon, 02 Aug 1999 19:26:49 -0400
Hi gang,

Back in the June 1985 issue of Ham Radio Magazine, I wrote an article on
"Protecting Equipment". While primarily aimed at VHF/UHF, many techniques
shown are useable on HF as well. The coil of coax was shown.

Another interesting and simple scheme is also shown, namely the placing of
a 5 foot long (or so) piece of conduit over RG-8 type coax. It acts like a
high impedance to lightning but otherwise no affect on the operation. check
it out.

73,

Joe, W1JR

>Hi Donald and anyone else interested,
>
>Donald said:
>
>> For years I have added a coil of two or three
>> windings about 20" to any coax that comes into
>> the shack.  I bare the coax outer covering above
>> the balun spot to expose the braid on the outer
>> lead.  Then I run a soldered a connection from
>> the braid directly to ground STRAIGHT DOWN.
>
>There are many methods of protecting your gear from lightning.
>Usually the correct and most reliable methods are just not feasible
>if you live typical residential house or apartment.  You need to pull
>little tricks.  Some work quite well actually.  A few turns of coax
>outside makes a nice choke.  Grounding the braid as Donald described
>should work just fine.  Sure, not as fancy as a commercial entrance
>panel and following every step in the Poly-Phaser manual, but better
>then just running the coax straight in.
>
>That reminds me of the time I visited a dumpy old shack that was
>being used for commercial two-way stuff.  This place was so dumpy
>that they even had plastic tarps over the radios to keep the
>rainwater that leaked through the roof from getting in the rigs.  A
>few turns outside in the coax, and the AC line cord had a big ugly
>knot tied in it.  I asked the "tech" about the knot and he told me it
>was for lightning protection.  He claimed he had replaced several
>completely blasted apart line cords, but the radios survived in fine
>shape.  I had to just shake my head, but then, it probably worked.
>Either that or the tech was pulling my leg.
>
>73 Jim K7SLI
>
>
>It
>> doesn't seem to make signals any  worse, and it
>> may have even helped some.  One thing, I've
>> never have lightning come into the shack.
>>
>> I am curious if anyone else does the same thing,
>> and what results they have had.
>>
>> tnx es 73 de n8csp
>>
>>
>>
>>
>>
>>
>>
>> --
>> FAQ on WWW:
>http://www.contesting.com/towertalkfaq.html
>Submissions:              towertalk@contesting.com
>Administrative requests:  towertalk-REQUEST@contesting.com
>Problems:                 owner-towertalk@contesting.com
>Search:                   http://www.contesting.com/km9p/search.htm
>
>
>
>--
>FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
>Submissions:              towertalk@contesting.com
>Administrative requests:  towertalk-REQUEST@contesting.com
>Problems:                 owner-towertalk@contesting.com
>Search:                   http://www.contesting.com/km9p/search.htm
> 

--
FAQ on WWW:               http://www.contesting.com/towertalkfaq.html
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com
Search:                   http://www.contesting.com/km9p/search.htm


<Prev in Thread] Current Thread [Next in Thread>