None of the posts yet mention this so I will: The name for this approach
is "electrostatic shield", a very effective technique where it applies.
73 Art
k6xt at arrl dot net
>
> Message: 1
> Date: Mon, 16 Oct 2006 11:41:34 -0500
> From: Mike Gorniak <mgorniak@genesiswireless.us>
> Subject: [TenTec] Coaxial Ground
> To: tentec@contesting.com
> Message-ID: <4533B63E.50209@genesiswireless.us>
> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
> Hi Gary,
>
> Probably the easiest explanation is to call it a "shielded ground wire". The
> coax inner conductor is the actual ground wire, and the shield keeps it from
> radiating.
>
> My 2nd floor installation was a nightmare, given that I was also very close
> to the antenna center, which was about 10 feet above the roof of my house.
> This was one technique I used to beat the "RF in the Audio" problem. I also
> used toroids and bypass capacitors in generous quantities.
>
> OF course, each RFI condition is unique in some way...YMMV.
>
> 73,
>
> Mike
> NM7X
>
>
>
>
> ------------------------------
>
> Message: 2
> Date: Mon, 16 Oct 2006 11:51:21 -0400
> From: "Gary Hoffman" <ghoffman@spacetech.com>
> Subject: Re: [TenTec] TenTec Digest, Vol 46, Issue 45
> To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
> Message-ID: <00f401c6f13a$f04ca5b0$9ee7254a@aa2iz>
> Content-Type: text/plain; charset="iso-8859-1"
>
> Mike,
>
> I'm curious. What is the theory behind this approach ? I'm always
> interested to learn more approaches to grounding.
>
> Gary
>
>
> ----- Original Message -----
> From: "Mike Gorniak" <mgorniak@genesiswireless.us>
> To: <tentec@contesting.com>
> Sent: Monday, October 16, 2006 11:39 AM
> Subject: Re: [TenTec] TenTec Digest, Vol 46, Issue 45
>
>
>
>
>>> Hi John,
>>>
>>> If you are going to run that wire down to a ground rod, you might try
>>> using coax instead. Attach the center conductor Only at the rig end, and
>>> connect Both the shield And the center conductor at the ground rod end.
>>> Another variation is to connect the center conductor Only at both the
>>> rig and ground rod ends, and then use a .1 or .01 mfd. capacitor to
>>> connect between the shield and the Center conductor at the ground rod
>>> end, or both ends.
>>>
>>> When I had my ham shack on the second floor, this configuration worked
>>> for me.
>>>
>>> Good Luck, and please let us know of your progress!
>>>
>>> 73,
>>>
>>> Mike
>>> NM7X
>>>
>
>
>
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