If you are using EZNEC and have the wire structure for the flags,
setting phase is easy.
1) model each flag with a source record (the two sources will be
assumed to be fed in parallel).
2) on the Sources window set the offset flag to "160" under "Phase".
This will allow you to check out the model and get your understanding
of the phasing confirmed.
Since these two antennas are lossy, the interaction will be very
slight, and assuming attention is paid to equal construction and
getting a 50 ohm feed, the usual two to one devices will work, with
160 degrees more 50 ohm coax to the flag doing the lagging.
Guy.
----- Original Message -----
From: "David Gould" <david.gould@btinternet.com>
To: <Antennaware@contesting.com>
Sent: Sunday, December 18, 2005 5:05 PM
Subject: [Antennaware] Help with modelling phased Flags
> My antenna modelling with EZNEC has been limited to simple antennas.
>
> I no longer have access to the land I used to use for beverages so
> would like to try a pair of end-fire flag antennas as described by
> ON4UN in his latest edition (4) of his "Low Band Dxing" (Fig 7.137,
> Page 7.95). I can model the basic wire structure, but do not know
> how to go about modelling the feed arrangement where the phasing
> angle needs to be 160degs.
>
> I would like to ask if anyone would volunteer to act as a "mentor"
> to
> give me some help to get started on this project, any offers of
> help
> would be much appreciated.
>
> 73,
> Dave, G3UEG
>
>
> _______________________________________________
> Antennaware mailing list
> Antennaware@contesting.com
> http://lists.contesting.com/mailman/listinfo/antennaware
>
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