I might have a chance to operate from a portable location this summer for a
contest or two but at the location they have no antennas, nor is there room
for any huge vertical, inverted L, guys ropes etc. etc. and no permission to
climb roofs, chimneys, or put a bolt in the building, nor touch the trees.
All very restrictive.
I might be able to erect a 35' freestanding fiberglass mast with a ZS6BKW.
Maybe. The ZS6BKW is basically a 94' dipole with a 40' downlead of 450ohm
ladeer line..which will be sloped slightly, as I don't see a way to get the
peak above 35'
Suffice to say, the best I MIGHT be able to do is sneak in this low
ZS6BKW(G5RV) as an inv. vee to run 10m-80m but I am looking for a way to
ALSO be on 160m to make a few dozen contacts in a contest or two.
I am thinking the peak of the ZS6BKW (G5RV like antenna) would be at max
35'.
For 160m, could I short the 2 leads of the 450ohm ladder line together where
they meet the coax run and sneak out 2 x 65' (bent) ground radials and
attach them to the braid side of the coax?
(maybe I'll even make up a switchbox so I don't have to be running around in
the dark a few times a night reconfiguring bare wires in an unfamiliar
location.)
I've read 3830 contest reports where folks have done this type of thing, but
of all the antennas I have ever had (many!_) I have never EVER tried this
shorting of the ladder line or coax and feeding what is a G5RV as a T-Top
vertical.
with a couple of radials.
I am not sure how a 40' tall vertical with 94' of toploading, models in NEC,
but it seems like it might be close-ish(?) to resonating on 160m. (will I be
in the ballpark?) What kind of matching will I need if any?
I could maybe even add more coax or ladder line to the "vertical" section
when on 160m, however it will also have to be sloped/bent and on or very
near the ground (probably not good, eh?)
I'll be using a modern transceiver with internal ATU.
I am not looking to run pileups on 160m.(where I am going is not rare, just
a nice summer place)..I just want to pick up a few 160m mults in a contest
or two.
Ideas? Remember, I am very restricted. Gotta have the ZS6BKW for my
antenna.and I may not be permitted to have more than 1 coax run out to the
antenna. I doubt adding a couple extra 65' legs is possible either. (no
square footage for that.
Thanks
Mike VE9AA
Mike, Coreen & Corey
Keswick Ridge, NB
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