----- Original Message -----
From: "g3ldo" <[email protected]>
To: <[email protected]>
Sent: Thursday, January 01, 2004 10:31 PM
Subject: Re: LF: Re: "T" versus "L"aerial
In the early days of LF experimenting we all thought Ts and Ls from
available LF commercial knowledge. It soon became apparent that for a
suburban QTH the shape of the antenna was unimportant. The trick seemed to
be to put up as much wire covering the greatest area and as high as
possible.
John, G4JVC had a long wire running the length of the garden, 3m high at
the
feed end and 12m high at the other. With this antenna and a TS-850 he was
able to hear a lot of DX that we couldn't (he was the first to hear
OH5TN).
All very electrically small antennas have the same half doughnut shaped
3-D
polar diagram on a computer model. Ground parameters have a huge effect on
small LF antenna performances so I guess they must compute return path
losses.
The one I use - Antenna Model - asks whether you want to take ground losses
into account and if so what conductivity figure to use.
Walter G3JKV.
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