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Ian Jackson[_2_] · April 5th 14, 08:46 AM posted to rec.radio.amateur.antenna

In message ,
writes
On Friday, April 4, 2014 9:16:01 PM UTC-5, Fred McKenzie wrote:

3. Ground is relatively flat. Drooping radials to approximate a sleeve

dipole is stretching the definition of a ground plane!

The best modeled version of the 5/8 with 5/8 radials scheme, I
consider more of a dual 5/8 collinear than a 5/8 ground plane.
You don't get the full 5.1 dbi free space gain of the straight
collinear, but you get fairly close.
But.. I don't really care about the name.. Just as long as they work.

I understand that my 2m 5/8 mobile antenna (on a magmount) is
essentially electrically a 6/8 (ie a 3/4 wave - hence a good match). The
actual whip is around 5/8, and the other 1/8 is the 3-turn spring steel
'loading' coil at the bottom end.

Again my understanding is that a 5/8 gives the maximum broadside gain (a
tiddly bit more oomph than a 1/2 wave), and if you make the antenna
longer, the predominant broadside lobe collapses, and most of radiation
moves to the higher angle lobe.

--
Ian