Ok, I have nine of these things; elevated, with four elevated
radials each so far; with plans now to add more radials.
Also, vines have found the radials to be a great place to hang
on to while spreading!
When first set up back in the late Spring, all were resonating
just where I wished:
TL160 on 1.830; TL80 on 3.520; not top loaded 40, on 7.050, etc.
I presume because of the vines, they resonate now below the band
edges. However, I use them anyway, getting a fine X=0 and
SWR=1:1 using the antenna tuner and an MFJ259B to bring
the tuner to exact resonance and presumably the antenna system
is conjugately matched, so all the power from the rig is eventually
radiated, less the line loss.
Now, as I add more radials, they will not be elevated and resonant
radials.
Rather will be strung out across the brush and vine tops, eventually
to be overgrown by the ever rapidly creeping green menace out here!
If I add 8 such ground wandering, longer than 90 degree radials, between
each pair of the present four elevated radials, I wind up with four still
elevated, and 32 more in the greenery. And am sure the resonant
frequencies of each antenna will again be lowered.
This could be "fixed" by taking each vertical down, adjusting
the length of the top section, setting back up (a back breaking
process for me!), checking the frequency of X=0, finding it
still not quite right, and then repeating the entire process
over again a few times!! And this effort on a hillside in the
midst of usually wet and buggy "jungle" vines and bushes,
in which everything, including me, the wiggly vertical element,
the radial wires, guy ropes, are constantly becoming entangled
requiring much blue smoke and added effort and time to
work free(To say nothing about the huge cane spiders
hanging about here and there)!
What do I loose, penalties paid in forgetting the system natural
resonance of each vertical set up, and just tune with the in-the-
shack "XMatch Classic Low Bander" tuner?? I presume the
radiating efficiency of these, as described, is pretty much
established by the lengths of the vertical elements, 38 feet
for both the 160 and 80 meter elements, and around
33 feet for the 40 meter unit. Plus, the perceived signal
levels each way may be increased, maybe 3 dB by the
added weed/vine mounted radials. I am sure the tuner
can bring these to conjugate match in the CW bands
of interest. Can I avoid the laborious tasks of repeated
take down, adjust, and re-set up to bring into "natural"
resonance if using the tuner as described?
Obviously I am looking for the easy way out, hi! Any comments?
73, Jim, KH7M
On the Garden Island of Kauai
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