A few suggestions, in no particular order:
Use the 140-foot pole as the top support of a bent, tilted 5/8-wave vertical
(about 150 feet will have to come down the other side (following what would
otherwise be a leg of the inverted vee). Matching should be as simple as
series capacitance (which makes exact wire length less critical).
Use the 140-foot pole as the top support of a full-wave loop (about 555 feet
of wire, depending on your design frequency). Feed with an electrical
1/4-wave of 75-ohm line.
Use the 140 foot pole as the support for two or more full dipoles facing the
directions you wish to work. (You would need about 217 feet of horizontal
clearance for the ends.)
If the 140-foot pole is conductive, use it as the vertical portion of a
VE2CV half-delta loop (use a drop wire if it's not conductive). Tune it at
the feedpoint for the best efficiency. Needs radials, however, if you were
using a vertical before... Also, with a tuner at the feedpoint, should cover
the entire band. (QST, September, 1982, page 28). He used a 50-foot tower
and 110.5-foot slanted wire for 80,40 and 20. Scaling it to a 140-foot tower
for 160 shouldn't be too hard. (The point was to have half of a full-wave
loop above ground with the rest as a reflection in the ground.) The bonus
here is the hanging of wire is no different than a tilted vertical.
Use the 140-foot pole as the support for four catenaries holding up four
bent 1/4-wave verticals around the pole fed as a four-square array. With 130
feet of spacing from the pole, you'd have 130-foot vertical elements with 15
feet vertical and 115 feet rising toward the top of the pole.
Use the 140-foot pole as the support for a bent vertical dipole. But, and
you'd have to model it, feed it at the bottom corner. This will require a
means of transforming impedance, but it would simplify routing of coax,
which, if you fed it in the center, you'd want to run at 90-degrees away
from the antenna (preferably away from the side where the elements are bent
? that might be difficult!).
Good luck. I wish I had a 140-foot pole to play with!
73, kelly
ve4xt
On 11/18/14 8:34 AM, "Jim Thomson" <jim.thom@telus.net> wrote:
> Date: Sat, 15 Nov 2014 08:40:39 -0500
> From: john nistico <electric911inc@hotmail.com>
> To: "towertalk@contesting.com" <towertalk@contesting.com>
> Subject: [TowerTalk] 160 meter antenna thoughts.
>
> In February I have the chance to once again operate from a baseball stadium I
> do work for on Long Island.In the past (see cq magazine June issue) I have
> used a 125 foot vertical supported from the 140 foot light pole with much
> success.I am thinking of an inverted v this year. A dipole is out as I will
> not be able to support in in an east west orientation and other ideas?
>
>
>
>
> John J. Nistico
> 911 Electric Inc.
> 516.325-8993
>
> ## Since u plan on running coax up the light pole to an inverted vee.....
> another option would be a quarter wave sloper.
>
> Jim VE7RF
> _______________________________________________
>
>
>
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