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Topband: DX Engineering Receiver 4 Square uing W8JI Passive Elements

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Subject: Topband: DX Engineering Receiver 4 Square uing W8JI Passive Elements
From: "Dave Robinson" <ag8b@chartermi.net>
Date: Sat, 26 Sep 2009 11:02:45 -0400
List-post: <topband@contesting.com">mailto:topband@contesting.com>
One variation of the this system that hasn't been mentioned is to use W8JI 
passive elements instead of the active elements.   DXE doesn't sell these 
passive elements, but you can find all the info you need at W8JI's web site.  
The advantages of the passive elements are that they are less expensive, you 
can locate them closer to the tx antenna without overload problems (noise may 
force may you to detune the tx antenna) and lightning isn't a problem.     

Because I've only got a a couple of acres to work with, I'm using only 70' 
spacing and so the dimensions need to be exact and the impedance of each 
element need to be pretty close to one another.    I use 4 20' long ground 
radials.  I use the MFJ-259B to closely set each elements resistance with a 
multi-turn pot.   Because the elements are so short (20' high plus 20' sloper 
wires) BC interference isn't a problem with the MFJ-259B

I usually have to run an external preamp like the ICE unit and on exceptionally 
quiet nights I can run a second unit in series.   Results from Michigan: I've 
heard and worked VQ9LA, 3Y0X, ST2A, SU9HP, 9X0R, ZL7T, 4X4ZR, EY8MM etc, so I 
think it works pretty good.   Is it as good as staggered phased beverages?   
No, but I do think it is close to a single beverage.   The RDF numbers in the 
ON4UNs Lowband DXing book confirm this.

Dave, AG8B
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