[CQ-Contest] ARRL-DX SSB (CQ WPX) : How were condx ?

Yannick DEVOS (XV4Y) yannick.devos at online.fr
Thu Mar 29 01:18:21 PDT 2012

Thanks Tom, Dave, for your comments,

Yes I knew the Moxon was rather sensitive to its environment.
However, since it was working so well to Europe, I was surprised to have bad performances to NA.
I think I will keep it heading 330 degrees so it give me a could coverage of Europe, part of Africa, part of NA and even some part of SA.

Two years ago I built a portable Moxon for 17m.
While it was exhibiting a good SWR and allowing me to make some DX QSO for the first time on 17m, it was far from being like a real Moxon.
The "tip-to-tip" coupling was good because the "legs" were supported by the spreaders.
The main parts of the driver and reflector were not however, and they were neither perfectly straight neither perfectly parallel when the antenna was swagging with the wind.
If you want a Moxon beam to perform nominally, it has to keep perfectly its shape.
That said, you can still have fair performances being a little bit of frequency (using your ATU) or having the elements not perfectly in place.

Yannick DEVOS - XV4Y

> I remember reading Cebik's design articles on Moxon antennas where he 
> pointed out their advantages (smaller size, wider bandwidth), but one of 
> the things he noted was their strong degradation due to nearby metallic 
> structures.  The Moxon design is very dependent on tip-to-tip coupling 
> of the elements and it doesn't take much to throw that off.
> 73,
> Dave   AB7E

More information about the CQ-Contest mailing list