I don't fully agree with the way it is shown on that picture. I would rather
see the grounding wires taken straight down and the feeders swooped off to
the side, observing minimum bend radius of course. Additionally keep the
ground wires from the outer bonds to the ground plate junction less than
0.5m.
Just my 2 satang worth.
Martin, HS0ZED
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of K8RI on TT
Sent: 26 March 2011 09:01
To: towertalk@contesting.com
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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>>
>>
>>
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