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Re: Topband: 160m inv vee questions

To: topband <topband@contesting.com>
Subject: Re: Topband: 160m inv vee questions
From: Bill Tippett <btippett@alum.mit.edu>
Date: Mon, 2 Apr 2018 07:35:21 -0400
List-post: <mailto:topband@contesting.com>
This plot shows my low inv-V (30m apex is only 0.19 wavelengths) compared
to my 3 element parasitic vertical.  Study the relative gain vs TOA plots
carefully:

Ooops...bad link.  Use this one:

http://users.vnet.net/btippett/new_page_10.htm

On Mon, Apr 2, 2018 at 7:10 AM, Bill Tippett <btippett@alum.mit.edu> wrote:

> FYI in response to two recent threads:
>
> http://lists.contesting.com/archives//html/Topband/2018-03/msg00139.html
> http://lists.contesting.com/archives//html/Topband/2018-04/msg00043.html
>
> This plot shows my low inv-V (30m apex is only 0.19 wavelengths) compared
> to my 3 element parasitic vertical.  Study the relative gain vs TOA plots
> carefully:
>
> http://lists.contesting.com/archives//html/Topband/2018-03/msg00139.html
>
> My observations over the past 14 years comparing both:
>
> 1.  The vertical array is best 99% of the time.  Usually by ~10 dB to the
> NE (e.g. EU/W1 from here).  From the plots you can see this equates to TOAs
> (<20 degrees).
>
> 2.  The inv-V (wires running NNW/SSE) is occasionally (1%of the time) much
> better to EU or other directions at my local sunset or sunrise.  This is
> striking when it happens and is easy to detect since the inv-V is also
> better for RX than either Beverages or an RX4SQ.  This is clearly some sort
> of high angle mode around SR/SS and it usually lasts for <30 minutes.
>
> 3.  The inv-V BW is much broader than the vertical array which is very
> narrow (~30 kHz).
>
> 4.  TX antennas are separated by about 100m on different towers and the
> 30m inv-V height is near optimum for maximum radiation straight up
> (intentionally).
>
> 5.  The inv-V also works well to the SE (Caribbean/SA) even without SR/SS
> enhancement.  I have no idea whether how it would behave if rotated 90
> degrees since my site doesn't allow for that.
>
> Just FYI,
>
> Bill  W4ZV
>
>
>
>
>
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