Your note is exactly why I swerved away from the 4 square and I am cabling
mine as a 4 el parasitic... those phasing lines are gonna be right over a
narrow range only, and 160 has more delta-reactance per kc, than any other
ham band... the use of a switched coil at the bottom to pull it down to cw
range is just fine... the difference in efficiency from full size is
un-measureable in the real world... btw, you may want to experiment with
switched phasing lines also...
On a parasitic array, leaning elements have little influence as long as the
average spacing is ok.. I'm not absolutely sure about a driven array, but
since an element does not know how it is excited, it _should_ work just the
same... you could model it.... my array is leaning considerably... the bases
are a 100 foot from the tower and the tops are 30 foot... the spacing was set
after many modeling sessions in 5 foot increments with eznec, which predicts
a gorgeous pattern with this arrangement... now if I can just live up to
Uncle Ezee's expectations...
R.E. tuning... I model mine and after the array is optimized, I model the
resonant frequency of a single element, with the others removed from the
field electricallly..
As I install, I tune each one to that frequency, with the others electrically
removed from the field... I have a dpdt relay at the juncture of each of the
verticals/elevated radials... I slip the corner of a dollar bill between the
contacts, which isolates/translates the quarter wave vertical element down to
80 meters ( I borrow the bucks from the xyl - and keep em :)... and I have
ground stakes, with a long lead and an alligator clip... I use this to take
one end of one of the elevated radials to ground, which translates them up to
the 320 meter band ... then I tune the one I'm working with... much easier
than unbolting all the connections, etc... The Autec RF1 is worth it's weight
in wildcats for this...
I will note that I have 2 of the elements complete, tuned and working and I
amazed some of the hairy(er?) denizens of 160 last night with a front to back
demo (unplanned)... I was chattering on AM with some stations in pa , va and
ia, when a very weak station broke in from northern michigan... no one else
responded and I switched to the north to acknowledge him... the others
noticed the difference in my signal immediately and started asking
questions... I was not trying to show off and I had gotten on the band to
spend a few minutes on AM, a mode I have not used on many years... When I
checked into the group I initially said I was using a vertical (no
elaboration), so they were not aware that it is a parasitic beam... but in
thinking about it afterwards, all, but one station, were 135 degrees
(roughly) off the beam heading to the NE, which dropped them into the rear
quarter notches in the pretty pattern that ezee predicts... they said I was
S9 before and that I almost(2)/did(1) disappeared when I switched... so, ezee
must be doing something right...
The 80m 4el parasitic will have non-leaning vertical elements, but doubt I
will have the last 60 foot of tower up in time to install the array for
cqww... durn...this working for a living really interferes with the important
things in life...
Denny
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