[TowerTalk] Discoverer 7-2 or Cushcraft xm-240

[Georgens, Tom]

I echo all the comments on the W6NL Moxon.  I have built two from scratch and they are both in operation at my station 8P5A.

All cutting was done on a table saw and all element drilling was done with a cheap Home Depot drill guide.  I had a friend with a drill press drill the brackets.

Could not be happier with the antenna.  I had a Discoverer 7-3 before and spent more time maintaining it that on all the other antennas combined.    I don't know that I would recommend this antenna over the Cushcraft.  I had an old 402_CD which worked well, but had limited bandwidth and some reliability issues of its own.

One thing to consider is installation of a Moxon.  On a free standing or crankup tower it is no different than any other antenna.    On a guyed tower the odd geometry can be challenge if you try to twist it through the guy wires or assemble at the top of the tower.  Tramming or a crane works better if that is an option.  Even with an experienced tower person, we had to drop a guy at each level to get it to the top.

Happy to answer any questions off line

73, Tom W2SC
-----Original Message-----
From: TowerTalk [mailto:towertalk-bounces at contesting.com] On Behalf Of Tony Brock-Fisher
Sent: Saturday, March 15, 2014 3:48 PM
To: Towertalk
Subject: Re: [TowerTalk] Discoverer 7-2 or Cushcraft xm-240

I have to second what Paul, W0AD said about the W6NL Moxon. I replaced a 
CC shorty-forty with the Moxon design and the difference is NIGHT AND DAY,

-For the first time EVER, I find a frequency on 40 (never a 'clear' one, 
just one where nobody comes yelling in your face to QSY). I call CQ for 
10 minutes, and I notice that the frequency is getting QUIETER! Folks 
are moving away from me because I am LOUD.

-The SWR is much better than the shorty-forty. Even with 'secret' 
compromise settings, the shorty-forty will be over 2:1 when you go up 
high in the band - such as operating split in a SSB contest. With the 
Moxon, the SWR is below 1.5 anywhere - no need to retune the amp.

-There are no coil losses. Talking to W1JR, the coils on the 
shorty-forty are lossier than you think - as the bandwidth is wider, so 
the Q is lower, than predicted by modeling.

-The elements are longer, so they have more directivity in and of 
themselves. This adds to a better pattern, more forward gain.

All in all, between the coil losses and the directivity, I'd say it is 
~4 db better than the shorty-forty in forward gain. That's a lot on 40m!

Contact me off-list for details. I built one from scratch and would do 
it again in a heartbeat.

-Tony, K1KP
_______________________________________________



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