----- Original Message -----
From: "Bill Turner" <dezrat@copper.net>
To: "K4SAV" <RadioIR@charter.net>
Cc: <towertalk@contesting.com>
Sent: Saturday, November 04, 2006 11:05 AM
Subject: Re: [TowerTalk] Inverted Vee vs. Dipole QRN
> ORIGINAL MESSAGE:
>
> On Thu, 02 Nov 2006 16:51:32 -0600, K4SAV <RadioIR@charter.net> wrote:
>
>
>>An inverted vee is not more susceptible to QRN than a dipole.
>
> ------------ REPLY FOLLOWS ------------
>
> I have to disagree, for two reasons:
>
> 1. An inverted vee has a vertical component of radiation, and man-made
> noise is predominantly vertically polarized, so an inverted vee will
> pick up more man-made noise than a dipole.
The question was about QRN (natural), not QRM (man made).
However QRN is predominately vertically polarized and in theory the
inverted - V would hear more. In practice I doubt the user would be able to
tell the difference most of the time as the difference is not great. In the
past I've noticed substantial differences between true verticals and either
type wire antenna "at times". I've never been able to tell much difference
between the inverted V and dipole. What I have noticed when the bands are
really busy with lots of QRM the lower angle of the vertical discriminates
against the closer stations or stateside QRM so I can hear the DX much
better.
>
> 2. An inverted vee with an apex angle of about 90 degrees is almost
> perfectly omnidirectional in the azimuth plane, whereas a dipole is
> quite directional, having sharp nulls off the ends. If you are lucky
Again I've never noticed the sharp nulls off the ends of a dipole BUT and I
hasten to add that by nature they are much closer to the ground (75 and 160)
than the big antennas (20, 15, & 10) and as such have quite distorted
patterns. IE they become much higher angle radiators with less defined
patterns.
Roger Halstead (K8RI and ARRL 40 year Life Member)
N833R - World's oldest Debonair CD-2
www.rogerhalstead.com (Use return address from home page)
> enough to have the dipole's end pointed toward a noise source, the
> dipole will be quieter than the vee.
>
> Bill, W6WRT
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