Towertalk
[Top] [All Lists]

Re: [TowerTalk] Feed Point Choke Question

To: towertalk@contesting.com
Subject: Re: [TowerTalk] Feed Point Choke Question
From: Jim Brown <jim@audiosystemsgroup.com>
Reply-to: jim@audiosystemsgroup.com
Date: Sat, 7 Nov 2020 10:56:35 -0800
List-post: <mailto:towertalk@contesting.com>
I will not be drawn into debates about scientific concepts that have long been well understood.

73, Jim K9YC

On 11/6/2020 12:58 PM, Artek Manuals wrote:
Jim

Show me the ACTUAL antenna range pattern measurement data  with and without the common mode choke on a a similar antenna, with a reasonable SWR ( LESS THAN 1.5:1)  and the feed line has been brought down perpendicular to the plane of the antenna and I will concede you the point

Dave
NR1DX


On 11/6/2020 3:37 PM, Jim Brown wrote:
On 11/6/2020 12:28 PM, Artek Manuals wrote:
The short answer is how tight you make the turns will have little real world effect.

That short answer is WRONG.

Use the RG-8X I would probably use the #31 core over the
43 . The poor mans 8 turns of coax 4-5" in diameter without ferrites will probably actually work as well.

Define "work." The important thing a choke should do is kill common mode current on the feedline that couples noise to the antenna and fills in nulls in the antenna's pattern. That "poor man's" solution won't do much for that. If "work" means it won't overheat, yes, it would "work."

Depending on SWR and feed line dressing (always perpendicular to the plane of the beam the need for choke at all� is arguable

It's arguable only if you don't understand the problem, or don't care about noise or the antenna's nulls.

73, Jim K9YC
_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk


_______________________________________________



_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
<Prev in Thread] Current Thread [Next in Thread>