Roger:
I understand why you might think that weatherproofing a ground clamp on
braided coax like RG-8/u might be tricky. However, it can be done if you
apply the proper materials.
I posted some time back in 2001 about applying homemade ground clamps
to my runs of RG-213 at the top and bottom of my tower:
http://lists.contesting.com/archives//html/Towertalk/2002-07/msg00698.html
. You can see photos of how Joe KC2TN followed my suggestions here:
http://lists.contesting.com/archives//html/Towertalk/2007-10/msg00356.html
. The trick to getting a proper seal is to use Scotch 2200 Mastic Pads to
cover the clamp and to bridge the cut in the coax shield.
http://s83.photobucket.com/albums/j282/ersmar/?action=view¤t=Scotchmastic.jpg
,
http://s83.photobucket.com/albums/j282/ersmar/?action=view¤t=Masticsealed.jpg
, and
http://s83.photobucket.com/albums/j282/ersmar/?action=view¤t=Scotch88.jpg
.
73 de
Gene Smar AD3F
----- Original Message -----
From: "K8RI on TT" <k8ri-on-towertalk@tm.net>
To: <towertalk@contesting.com>
Sent: Friday, March 25, 2011 10:01 PM
Subject: Re: [TowerTalk] Grounding Question
> On 3/25/2011 9:25 PM, Jim W7RY wrote:
>> If you would like to see how the professionals do it, take a look here:
>>
>> http://www.maplenet-inc.com/grounding
>
> I really dislike that approach on the types of cables most of us use. It
> works well with solid copper jackets like Heliax (TM), but I'd not want
> to use it with regular coax using either a braid or foil shield. Also
> weather proofing these on braid and foil shields is much more critical
> than on a coax with a solid copper shield. I much prefer the use of
> bulkhead connectors for those grounding points which I do at the top and
> bottom of the tower.
>
> I do use the ring around the base of the tower and tie that into ground
> runs going out to about 80' from the tower.
>
> 73
>
> Roger (K8RI)
>
>
>> Motorola's Communications Site Ground Standards know as R56, are all
>> written
>> around the NEC and TIA/EIA standards. As well as many MIL documents. I
>> happen to work for one of the authors.
>>
>> W8JI has some good stuff on station grounding. www.w8ji.com
>>
>> Do some Google searching on Motorola R56 or tower site grounding or ham
>> station grounding etc. You will find lots of info.
>>
>> 73
>> Jim W7RY
>> Motorola
>>
>>
>> --------------------------------------------------
>> From: "Jim Brown"<jim@audiosystemsgroup.com>
>> Sent: Friday, March 25, 2011 10:00 AM
>> To:<towertalk@contesting.com>
>> Subject: Re: [TowerTalk] Grounding Question
>>
>>> On 3/25/2011 6:08 AM, Larry Libsch wrote:
>>>> I must be misunderstanding something . How do I attach my
>>>> coax shield to the outside common point and also attach it to my radio
>>>> inside the shack?
>>> Since I wrote the grounding chapter for Steve's book, I'll attempt to
>>> clarify.
>>>
>>> One ancient and accepted method of accomplishing this is often called a
>>> "ground window," where coax cables go through lightning arrestors
>>> (Polyphaser, ICE, etc.) that are bonded to a conductive plate (usually
>>> copper) where they enter the building, and that plate is bonded to the
>>> ground system. The coax from the antenna has a PL259 that screws to the
>>> arrestor on the outside of the wall and a coax jumper with PL259s on
>>> both ends goes between the arrestor and the radio.
>>>
>>> Several brands of arrestors are sold in "feed-through" form, so that the
>>> plate can be installed in a wall (or an actual window). There's nothing
>>> magic about the feedthrough arrangement, it's just a mechanically neat
>>> way to do it.
>>>
>>> The MOST critical part of all of this is the bonding together of ALL
>>> grounds associated with your home and shack -- power service entrance,
>>> shack, CATV, telco, other lightning arrestors, building structure, all
>>> ground rods, etc.
>>>
>>> 73, Jim Brown K9YC
>>>
>>> _______________________________________________
>>>
>>>
>>>
>>> _______________________________________________
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>>> TowerTalk@contesting.com
>>> http://lists.contesting.com/mailman/listinfo/towertalk
>>>
>>>
>>>
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>> _______________________________________________
>>
>>
>>
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>
>
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