[Elecraft] Feeding the Halfwave Ant

[Don Wilhelm]

Steve,

If your tuner is of the L network type (like the Elecraft auto-tuners), it
will have a difficult time matching the high impedance of a half wave end
fed antenna.  If you want something similar, use the W3EDP length antenna -
an 85 ft. radiating section with a 17 ft. counterpoise wire in place of the
half wave.

If you insist on feeding a half wave antenna at the end, plan to use a
parallel tuned circuit to tune it - the Z-match tuner is a multiband tuner
of that type and will tune high impedances fine.

I personally consider the center fed configuration to be less troublesome
because it is inherently balanced, but then you have to set it up in a
balanced configuration to preserve that balance, and I usually end up with
an inverted VEE configuration which works just fine with one support.

73,
Don W3FPR


> -----Original Message-----
>
> This may be silly question? I'm trying to cut down on set up time and
> weight for my backpacking journeys into the field with QRP gear. The
> end fed halfwave or random wire 'sounds' good to me becasue of the no
> feed line and a simple LC tuner can be used. Opposed to CF halfwave
> with balanced tuner (heavy toriod) and additional feedline weight?
>
> OK heres the REAL question: once you have a halfwave, (5/8 or 3/4 wave
> whatever) suspended in the tree or on a pole, Does it really matter
> how it gets fed? Wouldn't end feeding give the same result (or
> should?) as center or even offset feeding? Of course this assume a
> it's over a pefect ground etc (But truth is I'm usually over very poor
> ground situation)
>
> 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. But may limit where I park my tent and
> how the antenna gets supported etc? Am I missing something -- w/my
> limited knowledge of antennas?
>
> My experience has been the CF antennas have out performed (or so I
> think) than my end fed setups? But I may not have properly match the
> EF ants or I may be CF-biased from what I've read? Where's the TRUTH??
>
> Steve/n0tu
>