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Message-ID: <4B179DE6.3050608@usa.net>
Date: Thu, 03 Dec 2009 12:15:50 +0100
From: Alberto di Bene <dibene@usa.net>
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References: <38A51B74B884D74083D7950AD0DD85E828AAF4@File-Server-HST.hst.e-technik.tu-darmstadt.de> <4B16987B.9000002@usa.net> <op.u4bnzwomyzqh0k@pc1>
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Subject: Re: LF: Results of optimising an active antenna
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Roelof Bakker wrote:
> Hello Alberto,
> 
> I have used a large coffee tin (30 cm high and 27 cm diameter), for a  
> passive electric field probe.
> The capacitance was way to high for active circuitry. Instead a rf  
> transformer wound on a hefty high mu toroid was used to couple the antenna  
> to the coaxial feedline. It worked, though the bandwidth was restricted to  
> LF and MF.
> 
> An other example is using a small diecast alluminium box (50 x 50 x 30 mm)  
> with the buffer amplifier mounted inside.

Hello Roelof,

   thanks for the info. Well, 30 x 27 cm was rather a big coffee tin...
Who knows, may be a small beer can, those of 33cl, has the right capacity
towards ground... must do an experiment. Suggestions about the brand of the
beer are gladly accepted... :-)

73  Alberto  I2PHD