There was an article that came out some years ago in CQ magazine.
The author made a wire cage around a tree. It consisted of 4-135 foot
wires. The wire went up the tree to the 50 foot level, hooked to an
insulator. The remaining 65 feet went out and back down the tree, connected
to a ring around the tree (where all the wires were connected together). An
insulator was placed in the center of the longer wire to pull it out tight.
There were 4 wires like this. For precise tuning, there were some top hat
wires at the top laying in the branches.
I tried one and it worked pretty darn good. It was a lot broader than the
single wire it replaced. 7
I know, the tree will absorb RF. But not as bad at the lower freqencies.
73
Tom W7WHY
Dave,
Before you go overboard with the aluminum, consider a (wire) cage vertical
supported by the tree. Just run multiple wires up the trunk, bonding them at
the base and at the top. As for an 1/8 wave vertical, don't rely solely on a
tuner but rather make it as near a resonant antenna as possible. Perhaps the
simplest method is to string it up the tree as high as possible and then let
the remainder slope back towards earth.... an inverted el. The current
maximum of the antenna is at the bottom anyway so it's a better method than
center loading a shorter antenna with a coil. Inductive loading is normally
my last resort as it has the greatest losses, translating to reduced
efficiency. My preferences are 1: full size, 2: top loaded, 3: center and
top loaded, 4: center loaded. I don't have anything that is loaded only at
the base. Again, try the cage vertical and see if additional wire don't
help. it's still stealthy.
gl,
Jim W5QM
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