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Re: VLF: looking for a simple-to-build sub-9KHz E-probe

To: [email protected]
Subject: Re: VLF: looking for a simple-to-build sub-9KHz E-probe
From: Andy Talbot <[email protected]>
Date: Sun, 3 Oct 2010 13:00:16 +0100
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Use your existing or whatever loop, but before any preamp add a high pass filter.
 
Take a look at  http://www.g4jnt.com/LF_HPF.gif    for a design using off the shelf component values for a 50 ohm design with Fc = 6kHz (to allow you to receive the 6900 kite signals, and provide > 80dB of rejection of 50Hz and its harmonics.
 
If you want a another design - for a different Zo, Fc etc -  have a play with AADE filter designer.   It whiles-away a wet sunday afternoon (meanwhile checking there are no smoke signals) if nothing else :-)
 
On 3 October 2010 12:31, Daniele Tincani <[email protected]> wrote:
Hello VLF,
 
just to try to improve a bit my reception at < 9KHz, I'm looking for a easy-to-build E-probe design.
Currently I'm using a very simple system (http://www.vlf.it/easyloop/_easyloop.htm) which works very good but
unfortunately it has to succumb to the intense hum I have all around. In fact, I live on the 5th floor of a 6-floors
jointly-owned building in a sub-urban area (in Livorno, Italy). I have a motorway, a railway, electric powerlines, mobile phone antennas, etc. all within a few hundreds meters.
I don't know if an E-probe would survive better than a loop in such an hostile enviroment :-) However, a short whip is for sure easier to build and to handle than a 70 cm x 70 cm, 40-turns loop like the one I have currently.
I'm also looking for an homebrew design as off-the-shelf receivers look to me a bit costly compared to my VLF budget :-)
Any suggestions/references?
 
Best regards
Daniele


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