It was intended to compare to the specific Moseley model, a disclaimer the
author clearly makes. He didn’t optimize the antenna because Moseley didn’t,
either.
He also admits he ignored the other lumped inductances in the actual antenna,
which probably hampers 20m efficiency even more than his model represents.
I suspect that particular Moseley was designed to appeal to folks transitioning
out of a ground-mounted vertical, for whom the Moseley would appear to be a big
upgrade, primarily for being up in the clear rather than for any electrical
advantages over a dipole.
73, kelly
ve4xt
> On Jan 10, 2016, at 10:16 AM, Joe Subich, W4TV <lists@subich.com> wrote:
>
>
> The model used for the yagi is far from optimum and contains losses
> not likely to be present in a well designed antenna. The losses in
> a half size element are typically less than 0.5 to 1 dB unless the
> loading/matching circuits have extremely low Q.
>
> That said, Moseley antennas have been found to be quite inefficient in
> actual range tests (see the W0AX/K7LXC tribander books) to the point
> of showing loss compared to a dipole on some bands.
>
> 73,
>
> ... Joe, W4TV
>
>
> On 1/10/2016 9:27 AM, dw wrote:
>> I read an interesting article in eham where EZNEC was used to compare a
>> specific commercial beam to a dipole.
>> I guess I was a little surprised at the results.
>> The article is here.
>>
>> http://www.eham.net/articles/35421
>>
>> It goes to the question of whether or not a given antenna solution
>> represents an improvement significant enough to warrant investment.
>> I wonder how others formulate return on investment considerations.
>> Perhaps years of experience, and some "been-there-done-that", have
>> allowed you to develop some golden-rules about antennas?
>>
>>
>>
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