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Re: LF: Results of optimising an active antenna

To: [email protected]
Subject: Re: LF: Results of optimising an active antenna
From: Alberto di Bene <[email protected]>
Date: Wed, 02 Dec 2009 17:40:27 +0100
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Stefan Schäfer wrote:

My Conclusion: It seems that a short receiving antenna can bee seen as a capacitive divider out of the capacity between far field and antenna and the capacity between antenna and ground. If the wire length is to much, the input stage becomes nonlinear/goes into saturation. If the height above ground is increased the signal comes up, but not the signal/noise ratio(surely there will be a benefit if such an antenna is placed in a region with heavy local qrm. Then, the height should be increased and the wire length can be decreased). So, one cannot say “the more the better” 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 can...



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