Message-ID: <00cb01c19878$1b38f6a0$6a01a8c0@cianciolo>
From: "PC" <paulc@snet.net>
To: rsgb_lf_group@blacksheep.org,  lowfer@mailman.qth.net
References: <3C39E6F2.6C1C0918@netscapeonline.co.uk> <004801c197ba$645b49a0$1700a8c0@home>
Subject: LF: Receiving loop very close to the ground
Date: Tue, 8 Jan 2002 14:10:15 -0500
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Gentlemen,
I have 3 sort of odd questions that have been on my mind for awhile
Has anyone ever used a multiturn air core loop for LF that was mounted very
close to the ground?

I have built a very nice loop that I can tune fron 210 Khz to 73 Khz very
nicely.  Right now it is mounted on a few inches above the ground.  Now I
know that when raised to its final resting position 5 feet or so above the
ground that it is likely to change freq. range sligthly.

Here are my questions

I know that I can illuminate(to some extent) a light bulb by connecting it
to the hot side of the mains and grounding it to the earth indicating that
there can be significant current flow in the earth at 50/60 Hz.

1) Can there also be significant flow at harmonic frequencies of the 50/60
Hz?  If so does this mean that an antenna low to the ground like mine, could
be picking up some of that energy that may be in the LF bands?
Would raising it to 5 feet help eliminate some of that noise?

2) Does raising a loop have any effect on the received signal strength other
moving the antennas resonance point?

3) Is it possible to shield one side of a loop antenna  with say wire
fencing a few feet away to  elimiinate noise coming from 1 direction and
thus making the unidirectional instead of bi-directional.

After all are not we playing the game of signal against noise.  To extend
the range of a given station should much consideration be given to
minimizing the undesirable noise, either man-made or natural ?   Isn;t the
noise the limiting factor here?

Please tell me if I am all wet...  I will go get a towel

Thank you for information on these topics


Paul A. Cianciolo
W1VLF