Good Morning All...
...And many thanks to both Mike & Garry for sharing their experiences with
me in the matter of my travails lowering the SWR of the north leg of my
3-element phased inverted "L" array...
After separately raising BOTH the vertical portion of the antenna, as well
as the horizontal end, the best "final" improvement that I could achieve was
an SWR of about 1.75:1. This morning --- in a cool, light drizzle, no
less! --- I removed 6' of wire from the "L's" overall length of 170', and,
after judicious tweaking of the resonating base air variable capacitor, a
1:1 SWR at 1819-KHz was finally attained.
I then proceeded to bring the resonances of all three elements to within a
few KHz of each other, but found that the air variable capacitor in the
south "L" was not adequate to do the job (the antenna resonated at about
1860-KHz, or so, with the plates all fully meshed). With no room inside the
Folger's coffee "doghouse" for anything physically larger than the capacitor
already in there, I measured off about 2' of some scrap RG-58 coaxial cable
that I had on hand, "guesstimated" its overall capacitance to be some 40+
pfd., and installed this --- with one end fully open, of course! --- in
parallel with the existing air variable...
Voila!
After some back & forth jockeying of the variable capacitor, resonance was
established at around 1814-KHz.
All three elements now play within a few KHz of one another, and the
system --- as a phased array --- is good to go for another year...yet it
never ceases to amaze me how directive this thing can be: on many occasions
the array actually hears better than either my K9AY loops, or 1500'
Beverage...
All that remains to be done now is the addition of more radial wires beneath
the 3 elements...and this shall be done in the coming days, courtesy of a
1000' NOS spool of two conductor zip cord which I bought at a yard sale this
past summer for the princely sum of (and I'm blushing as I type this!)
$10.00 --- CANADIAN dollars, at that, too! Hi Hi.
See you in the pile-ups...
~73~ Eddy VE3CUI - VE3XZ
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