I am also on a small lot in a city with a 1 wavelength 80 m.
horizontal loop. Actually mine is 1 w/l at around 4 mhz so where I
operate it's really more like .8 or .9 w/l. my lot is 50 x 100 feet.
I found that the practice of feeding the end of the ladder line by
tying each side together and working against ground is at best a
compromise. Firstly, it only works if you have a pretty long
vertical run of line. 30 feet vertical with 10 or 15 running over
the ground to get under the feedpoint of the loop isn't enough.
Secondly, you also have to have some kind of counterpoise. A tuner
ground rod isn't enough. You say you have trees. If you have room
for a 1 w loop on 80 then you have room to get on 160. I'd take the
tallest loop support (I'll assume it is a tree) and use that to hold
up a vertical wire. You run the wire up and through a marine pulley
on a dacron rope shot over the tree to make an inverted L. The
horizontal part of the L bisects the loop and ends at the opposite
corner, so for example if the vertical is in the NW corner, then the L
ends at the SE corner. Don't worry about it messing up the loop's
performance, it won't. And the loop won't affect the L either. Run
coax feedline out to the base of the L, do the necessary
counterweighting with pulleys if you are using trees, spring-load the
bottom insulator of the L if necessary so it can move with the trees
and put down a radial ring (don't use aluminum) and as always, put
down as many radials as you can with no. 14 solid, insulated that's
sold in 500 foot spools at most hardware stores. shop around for the
best price, invest in a wire stripping tool, staple down the radials
and they will eventually sink into the ground. don't worry if they
are only 10, 20, 50 feet long, just fit them in the corner of your lot
as best you can. If the horizontal part of the L is too long to fit
in the loop, you can bend it around like this > or this ) and it will
work fine. Does it sound like this is what I did? Bingo! and the
horizontal part goes right over my house and ends in a tree in my
front yard. Try this before you resort to loading, voyagers,
isotrons, etc.
73,
rob / k5uj
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