Hello to all.
Better weather and a few hours of daylight before leaving for work this
morning and I have a new 160m inverted L in the air but untried.
It didn't go as planned and I need some advice, reassurance or criticism
to know what to do next.
I had planned to put up about 175' of wire. The 40' tower and standoff
would get the vertical portion up 38' above ground and the rest would run
horizontal
to an unused wooden light pole with a wooden cross bar at the top to toss a line
over. The line went over the cross bar easily but brought disaster. The cross
bar had
rotted with age and the connecting bolts failed and down came the entire cross
bar and
no easy way to get a pulley up.
The only support nearby was a tree about 65' from the tower. 65' + 38' = too
short.
I remembered reading in the ARRL antenna book about linear loading (folding the
wire
back on itself) and it is supposed to have less loss than inductive loading or
traps.
I ran 12ga insulated wire for the vertical segment (40' long) to the insulator
on top then I ran
58' of 450 ohm ladderline (one wire connected to the 12ga vert. wire, the other
end left floating)
from the insulator at the tower cross bar to the insulator at the tree
(ladderline ends shorted
together at this end). This gives me approx. 156' of wire. Its longer than a
1/4 wave but short
than the 165 to 175' that I wanted.
The loading is in the horiz. section and most loss in inverted Ls is in the
ground loss around
the vert. and in ground loss under a long low horizontal section. The linear
loaded design I used
leaves the vertical section as it would usually be and the horiz. loading might
reduce ground loss
since its shorter. Is this right or would the horizontal section ground loss
still be the same (folded
wire loading means same length of wire at the same height)???
I had just enough time to lay down 3 ground radials (132' long) and 2 short
(25' long) before
leaving out to work. The tuner seems to like it but tonight will tell the tale.
Any thoughts on this???
Thanks
JerryC
KC8TES
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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