Topband
[Top] [All Lists]

Re: Topband: Dual feed for Pennants

To: Topband Reflector <topband@contesting.com>
Subject: Re: Topband: Dual feed for Pennants
From: Greg - ZL3IX <zl3ix@inet.net.nz>
Date: Wed, 24 Jun 2009 20:41:39 +1200
List-post: <topband@contesting.com">mailto:topband@contesting.com>
Greg - ZL3IX wrote:
> Hi all,
>
> I have the opportunity to extend my remote Rx site with a couple of 
> phased Pennants for the SE/NW direction.  I intend to cover both 
> directions with a single pair of antennas, and use relays to switch 
> between load and feed at each one.  I will be using W8JI's feed 
> transformer design with two transformers per antenna.  For convenience, 
> I am thinking of putting the relay in a box at one of the feed/load 
> points and running a coax right through the middle of the antenna to the 
> opposite feed/load point.
>
> My thinking is that, since the feed is isolated at each end, and the 
> coax is much shorter than a wavelength, there should be no pattern 
> distortion, and little noise pickup.  I will run a simulation on this 
> just to check, but I was wondering if anyone is using a similar 
> arrangement, and, if so, what the results are.
>
> 73, Greg, ZL3IX
>
>   
Several guys have told me that they have not managed to get this idea of 
running the coax between the arms of the antenna, to work. I have also 
realised that I would need two relays, or a 4PDT relay, as I would need 
to isolate the grounds as well.  Some pointed out that they use separate 
Pennants, but I think that this is overkill.  I will simply buy a few 
metres of extra coax so that I don't have to run it through the middle 
of the antenna.  I know that the dual feed system works, as I have used 
it before.

Thanks for your thoughts, guys.

73, Greg
_______________________________________________
Topband mailing list
Topband@contesting.com
http://lists.contesting.com/mailman/listinfo/topband

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