Towertalk
[Top] [All Lists]

Re: [TowerTalk] Clarifying on Mosley

To: "towertalk@contesting.com" <towertalk@contesting.com>
Subject: Re: [TowerTalk] Clarifying on Mosley
From: Bryan Swadener <bswadener@yahoo.com>
Reply-to: Bryan Swadener <bswadener@yahoo.com>
Date: Tue, 3 Dec 2013 23:59:14 -0800 (PST)
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
Thanks, Ward. I selected a Force12 C-4XL (similar to the C31XR 
but, with 40m added) based on your reporting (I bought the book) 
and because it came available when I was seeking a good antenna. 
As evidenced by signal reports in my log, I'm not disappointed.
It nests atop a US Tower TX-472. 
 
vy 73, 
Bryan WA7PRC 
http://www.tinyurl.com/wa7prc-tower

********************************
Date: Tue, 03 Dec 2013
From: Ward N0AX
Subject: [TowerTalk] Clarifying on Mosley

As one of the report authors, I thought I should jump in here.

The antennas were working models, borrowed from their owners for the 
tests, and assembled following the manufacturer directions to the 
letter.  The antennas were returned to the owners and reinstalled, 
continuing to be used on the air with no reports of significant 
failures.  After a first test indicated problems with a PRO-57 we 
offered to test a new antenna from Mosley in the second round but they 
declined for whatever reason.

The main issue with the Mosley PRO antennas we tested was on 10 meters 
where gain and pattern were definitely below spec.  It is quite possible 
that the manual's instruction not to use a balun at the feed point 
allowed significant feed line interaction to the point of upsetting the 
radiation pattern.  All other antennas did use a ferrite bead balun made 
by Force 12.  We did not test the Mosleys with and without a balun - 
there wasn't enough time and energy.

On the other bands tested (20 and 15 meters) they performed more or less 
in line with what you would expect from their boom length as did other 
tribanders such as the KT34XA, C31XR, TH11DX, Skyhawk, etc.

It would not be fair to characterize Mosleys as chronic underperformers 
across the board - numerous stations report good results from them.  For 
example, K4RO has a pair of PRO-57 beams and does quite well (his QTH 
has some rather dramatic topography to work with).  I don't see a lot 
of Top Ten stations using them and you can read into that whatever you 
want.  Although the electrical designs are pretty long in the tooth, the 
antennas are sturdy and robust - they stay up and withstand the elements 
pretty well.  There are other considerations such as operating bandwidth 
or wind speed rating that might be more important than forward gain to 
some customers.  Antenna selection is a complex situation with a lot of 
moving parts.

All of the data and the methodology is published in the report. I've 
wished another group would tackle reproducing the results but this is, 
after all, a leisure activity :-)

73, Ward N0AX
_______________________________________________



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

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