So has anyone tried using an elevation rotor on a high yagi? Why couldn't
you have the best of all worlds with a high yagi and point it up for high
arrival angles?
Michael WY6K
--- "Guy Olinger, K2AV" <k2av@contesting.com> wrote:
>
> I suspect that this is not so much a matter of where the main
> radiation pattern is, as where the nulls are in respect to the
> incoming angles.
>
> Very high antennas have better gain at the lower angles in marginal
> conditions, and those extra db's at the horizon are worth a lot. But
> the high antennas have deep nulls at common arrival angles. It would
> be easy and common to have the arrival angle on a minus 25 db null in
> the high antenna's pattern.
>
> This would be the exact phenomenon accounting for being "stomped" by a
> tribander. A 25 db null advantage to the tribander would be really
> hard to beat.
>
> Aside from getting some gain at very low angles, that's the main
> performing reason for stacks -- avoid pattern nulls on angle of
> arrival.
>
> 73
>
> ----- Original Message -----
> From: "David L. Thompson" <thompson@mindspring.com>
> To: <towertalk@contesting.com>
> Sent: Friday, February 01, 2002 5:21 PM
> Subject: [TowerTalk] Super high antennas on 10 to 20
>
>
>
> N4KG and W4ZV are right. The real high antennas can be at a
> disadvantage
> after the bands open. I had a 7 el 10 meter beam at 70 feet in 1970
> for the
> CQ WPX SSB and I had a great signal into Northern and Eastern Europe
> and the
> Far East but needed to lower the antenna
> to 40 to 50 feet when I got stepped on by a local with a 3el
> tri-bander at
> 50 feet in G or HP (then KZ5 Canal Zone).
>
> N4RJ tried all sorts of combinations and his final 10 meter set up was
> 35/65/90 and about the same proportion on 15 and 20. The 35 foot
> antenna
> was often left on South America.
>
> Spend time on the lower antennas and only add antennas at 180 to 200
> feet
> when its the last option.
>
> 73 Dave K4JRB
>
>
>
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