Interesting thread.
Bought three acres in the country here in central Ohio, where the
general ground conductivity articles feel we have good midwestern loam
soil. Well, MY soil is more like semi clay but it is agricultural
land. Corn and soy farming in particular.
When I moved here I had already sold off my tower and yagis (204BA and
KT36XA) , so was stuck with one 20 ft walnut tree as my highest
support. So I cut a 1/4 wave piece of #12 wire. shot it over the tree
and pulled it out to the east, sloping back to the ground.
I added one ground rod. Then slowly added several 130 ft #12 pvc
jacketed radials on the ground.
That season I worked LZ, 4X4, and a JA which opened my eyes to what
could be done on 160, a new band for me.
Over subsequent years I kept adding radials, and noticed each one
raised my swr. So I kept adding radials, eventually going to #17
aluminum fence wire, and shortening them to around 70 ft. The
proximity of the north PL forced me to use shorter wires...as short as
35 due due north and progressively longer to the NE and NW.
But at 28 radials, the swr no longer changed. so I stopped there.
Also, as the walnut tree kept growing, I was able to use 4'x 1.5" mil
surplus aluminum masts sections to push the vertical wire up to 52 ft.
So, today, the c. 130 ft INV-L ( pvc insulated #12 solid copper wire)
wanders up through multiple tree branches, to the top of the 52'
supporting mast, and slopes out to the ENE, terminating about 15 ft
above ground level. And that original ground rod now has 28 radials to
go with it.
W3HKK DXCC totals are now 175 worked/154confirmed.
A home brew coke bottle inductor shunts across the antenna-ground
connection and is played like an accordion to lower swr to nearly 1:1
during winter season when the radials are laid out across the grass;
and adjusted for the summer lawn mowing season when the radials are
coiled up and hung from the walnut tree to enable mowing without
chopping them up.(voice of experience. )
Five years back I added the SAL30 Rx antenna which I now use as my de
facto rx antenna on 160-40m.
Note: with the exception of a 5 el yagi at 15 ft, W3HKK uses an
all-wire antenna farm. The other antennas consist of monoband 1/4 wave
ground planes ( wires) with 4-8 elevated radials on 40--30-20-17-10m.
Seeking more oomph, on 40 and 20m, those GPs have been converted to 2
el vertical phased arrays. The 40m PA beams ENE and WNW, while the 20m
PA beams Asia (330 degrees) and SSE. ( in search of those final 10
remaining DXCC entities.)
I should add that wandering along beside the 160m INV-L is a second
INV-L, this one for 80m. However only about 8 ft of it is bent over,
so it is almost a qtr wave vert, and performs very well.
Most of my activity is in the 160m cw contests and in the WWDX-cw
contests, plus Dxing for the few rremaining new ones. .
Im not sure how to significantly improve the 160m L's performance at
this point. I am unable to raise the vertical leg any higher, and at
age 79 am definitely slowing down. Some thought has been given to
adding a couple of wires as a top hat but have been waiting for the 52
ft support mast to fall down on its own before attempting to make
changes.
Dont think any more radials are making a significant difference. since
the swr is not affected in a measurable way, per my AA54 antenna
analyzer. So guess this will have to do.
Thoughts?
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