Topband
[Top] [All Lists]

Re: Topband: RDF for Transmit 4 Square vs 8 Circle Array

To: topband@contesting.com
Subject: Re: Topband: RDF for Transmit 4 Square vs 8 Circle Array
From: Dennis <egan.dennis88@gmail.com>
Date: Mon, 16 Oct 2017 14:43:20 -0400
List-post: <mailto:topband@contesting.com>
Chuck

Having used both at a number of stations, I can speak with some experience here.

The biggest virtue I have found of an 8 Circle array is the ability to put a bothersome station or noise in a null.  Most of the time, you can hear a station in the 4-square beamed direction as well on the 4-square as on the 8 Circle.  You might even be able to put a bothersome station or noise in a null with the 4-square, but now he doesn't hear you either. The 8 Circle allows you to steer the null and maybe find a spot where the SNR is better,
and I've found both as valuable as the direction of maximum gain.

So, yes, you can hear things on an 8 Circle that you might not hear on a 4-square, but to me its more a question of nulls (of both other signals and noise) rather than a stronger
signal.

Dennis W1UE

On 10/16/2017 2:26 PM, Chuck Dietz wrote:
I was always told that, if one had a 4 square, there would be no need for a
receive array. I am finding this to be untrue when looking at the list of
RDFs. (Receive Directivity Factor) I have snooped through the archives
reading about RDF.
Can anyone verify this from actual experience?  Can you actually hear stuff
on an 8 Circle that can't be heard on the transmit 4 square? I would think
the difference might be more than marginal with the difference in RDFs of
2.48 db.  I'm not sure of the difference in takeoff angles. That could be
important too.
As a practical matter, the 8 Circle  is huge and expensive for a single
band antenna...

Chuck W5PR
_________________
Topband Reflector Archives - http://www.contesting.com/_topband

_________________
Topband Reflector Archives - http://www.contesting.com/_topband
<Prev in Thread] Current Thread [Next in Thread>