Message-ID: <4B16987B.9000002@usa.net>
Date: Wed, 02 Dec 2009 17:40:27 +0100
From: Alberto di Bene <dibene@usa.net>
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Z-USANET-MsgId: XID496NLBqOE9872X38
Subject: Re: LF: Results of optimising an active antenna
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Stefan Sch=C3=A4fer wrote:
>=20
> My Conclusion: It seems that a short receiving antenna can bee seen as=
 a=20
> capacitive divider out of the capacity between far field and antenna and=
=20
> the capacity between antenna and ground. If the wire length is to much,=
=20
> the input stage becomes nonlinear/goes into saturation. If the height=20
> above ground is increased the signal comes up, but not the signal/noise=
=20
> ratio(surely there will be a benefit if such an antenna is placed in a=
=20
> region with heavy local qrm. Then, the height should be increased and=20
> the wire length can be decreased). So, one cannot say =E2=80=9Cthe more=
 the=20
> better=E2=80=9D talking about the wire length!

It would be quite interesting if somebody could try to use, instead of a=
 wire, something
with a greater capacity towards ground, e.g. a can of beer (after drinking=
 the beer, of course...:-)
One of half liter (slightly more than 1 pint) could do, I think...

Maybe the increased capacity towards ground could make it more effective=
 than a wire

73  Alberto  I2PHD

P.S. And the entire active antenna circuitry could be placed inside the ca=
n...