Hi Laurence.....a bit odd ?? I presume your ground
is frozen hard now so winter ground loss. Just a silly thought I wonder because
a lot of your noise is from 30 to 50km if the mat is reflecting noise into your
loop that would in another position be absorbed in the ground ?? Then again I am
used to fence wire being steel or maybe coated iron .....magnetic conversion
rather than rectification, (never quite understood how Marconi's wire detector
worked) ?? ;-)) or is your neighbour using it as one electrode of his
Christmas lights ?
Best Wishes for the holiday
Alan
G3NYK
----- Original Message -----
Sent: Sunday, December 14, 2014 11:53
PM
Subject: LF: Noisy Earth mat...?
It so happens my 10ft diameter multi turn LF loop is now
plonked in the centre of an extensive earth mat consisting of bonded
welded fence wire, and about 100 x 100ft radials, numerous Earth
rods etc part of the MF tx system - Cant detect any diode type effects from
the mat.... Ive noticed since the loop has been surrounded by
this "mat" the induced noise into the loop has increased and the
loop effectiveness at 137kHz has been severely compromised (about
5dB on Transpolar paths over an optimized positional L400B) - the mat
and the loop are above 2.5 metres apart and not electrically connected
(galvanically isolated) with common mode chokes on the 400 coax -
there is no local coupling from the MF Marconi ie I can short it to ground or
bring it down and the background noise (somewhat White in nature around
-95dBm) doesn't change.... So I just wondered if I should move my
loop to a new Green field location away from the radial mat etc - anyone else
noticed similar?? Any suggestions? Thanks Laurence KL7L et
al ps over the pole is poor this evening so far with a little
spreading...
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