>>Have Topbanders used parasitic elements?
Yes, there are several parasitic arrays in use on the band.
Mine started out in 1998 as a "K3LR" array (described in ON4UN's "Low
band antennas" book) with a central tower as the driven element and four
sloping t-shaped parasitic wire elements giving three elements in each
of four directions. Two of the elements in line are used as a director
or reflector and the other two left floating. I later added a loaded
90-ft tower as a second director element toward Europe (4 elements total
to Europe). Each of the original 5 elements has 120 1/4 wave radials
laid on the ground (now mostly invisible, sunk in slightly) -- shorter
where they intersect at a midpoint and are bonded to adjacent radials..
Some more details at www.aa1k.us under "160 TX array."
KC1XX has one at his contest super station, described here:
http://www.kc1xx.com/antennas/160_array.pdf
K0HA has one that has proven quite effective from his Nebraska QTH:
http://k0ha.com/160m/160m.html.
My first recollection of the sloping reflector idea was in an article
VE2CV wrote in the Sept. 1984 QST.
4X4NJ (now K7NJ) used parasitic elements on a loaded tower to produce a
consistently big signal, described in a Feb. 1985 QST article.
K4ERO's article on sloping reflectors appeared in the ARRL Antenna
Compendium Vol. 4.
N6LF covers them in an article in the March/April 2003 issue of NCJ,
available here:
http://rudys.typepad.com/ant/files/antenna_array_single_support.pdf.
There's a good list of additional references at the end of that article.
73/Jon AA1K
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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