Jim -
I have done this - and it does work. You can get a couple of db of
gain - and perhaps even more importantly - some good F/B. The
distance should be something in the order of 45-65 feet or so (not
very critical) and you will have to do some work to determine where
the best F/B ratio is achieved. I used a broad band signal source and
a battery powered receiver that I could tune around. Get off on the
backside and tune the receiver for minimum signal. Adjust the length
of the radiator to move that to where you want it. A relay in series
with the element can be used to remove the element and go back to omni
direction. You can also put a coil in there instead and perhaps make
it a reflector to go to the opposite direction. You should see a very
sharp null off the back for 10 or 20 kHz. While this might not be the
place where you get peak gain - it's probably pretty close - and much
easier to find than a gain peak.
You will need an effective ground system for this to work. I found I
needed at least 40 radials (mostly 1/4 wave in my case) to make it
work well.
However, in the end, I went with a 1/4 wave phased array which has
much broader frequency coverage.
Tree N6TR/7
Boring, OR
On Tue, Dec 27, 2011 at 4:38 PM, Jim Miller <jim@jtmiller.com> wrote:
> I don't have a lot of room for antennas on my antenna restricted lot. After
> doing some reading on larger antenna farms I thought that a parasitic
> director added to my toploaded vertical might afford some gain toward
> Europe from my MD location. I've done a bunch of googling today but didn't
> find anything on this implementation specifically. Anyone have any links or
> thoughts on this?
>
> 73
>
> jim ab3cv
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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