[Elecraft] Feeding the Halfwave Ant

[Ed - K9EW]

Hi Steve,

As long as you mentioned the inverted vee, I thought I'd offer this to think
about.  I have been using a 20m center-fed inverted vee with very good
results.  And here's the great thing about it... it's a coil of TV
twinlead.  One end of the twinlead is split to form the two arms of the vee
(each approximately 17 feet long), and then the remainder of the twinlead
becomes the feedline which you can connect directly to your rig.  The only
constraint is that the feedline portion of the twinlead *must be* an
electrical half-wavelength long (about 29 feet, depending on the velocity
factor of the twinlead you use) in order to present a 72 ohm impedance to
your rig.  It's small (rolled up), lightweight, and requires one branch
about 30 feet off the ground for the vertex.  At this height, it's
approaching a half-wavelength above the ground which is great for
the radiation pattern.  The ends are tied off with small ropes to stakes (or
rocks) 30 feet from where the feedline would touch the ground.  This will
give you a 90 degree angle at the vertex.  It's balanced, so no
counterpoise.  And it works just like a "home" antenna.

72/73,
ed - k9ew


On 6/13/06, n0tu/Steve <n0tu.qrp at gmail.com> wrote:
>
> It seems to me the endfed half-wave inverted vee should give me the
> same result as the center fed inverted vee and have the benefit of
> leaving the feedline at home.