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HF end fed antenna without radials or ATU Single band

Mel Farrer, K6KBE
 

Here is a simple design for using an end-fed 1/2 wl wire without a ATU or radials.

Consider the simple "J" antenna used on the VHF bands.  That is, a 1/2 wl conductor on top of a 1/4 wl parallel matching section.

Now constructing a full size J would seem to be difficult, but really isn't.  Take a end fed 1/2 wl wire.  Now the current thinking is to put in a >9:1 transformer and put some kind of counterpoise to work.  Then a ATU.

What if you attached a 1/4 wl parallel transmission line to one end of the 1/2 wl wire and tapped up from the shorted end and matched to a 4:1 transformer? No radials, no ATU needed.  Can the matching section be jumbled up, well yes, with some care it can be stacked back and forth to some degree, and yes the simple twin lead speaker wire will work once you find the match point for 4:1. Builder's choice on the compromise.  BUT it is MUCH better than an compromise counterpoise.


Mel, K6KBE


Dave WD8CYV
 

Tried this on 20 meter rtty about 20 years ago     it works but was hard to tune      used it for a couple years

then went to a quad loop behind a dipole      like a ///   http://www.macoantennas.net/files/Y-Quad_2011.pdf

but with only the Horizontal Dipole