Hi Laurence,
Bit about using trees as antennas on the web.
Try keying in General George O. Squier into Google and see what you get.
Also in Scientific American, July 14 1919. p624
Regards
Peter, G3LDO
Sorry this is way off topic in relation to noise generation at LF/MF
but I know of one case (as I was the responsible investigating
engineer for a well known .gov dept at the time) of a tree causing non
intentional radiation as a result of mixing of 45Mhz TV signals from
Old Meldrum and a nearby "lowband" FM transmitter in Aberdeenshire -
the resultant non linear (arent they all) mixing process from this
Horse Chestnut tree (and it was the only one in the line of fire)
caused wobbly FM interference to a "fixed High band service" -
the Tree in question was about 5 miles from the TV transmitter on a
ridge and a couple from the VHF transmitter. The interfered with rx
source was some 100m from the Chestnut tree - It was confirmed that
the interference was coming from the mid section about 5 metres from
ground level - a case of the Bark being worse than the byte. Ill
leave you to guess how I cleared the problem.
Its the only one and only kind I came across with during my career and
I couldnt really believe what the test equipment was showing - but it
was - we didnt go interalia the causes and bio-causes of such an
effect but it did exist - honest gov.
youll know my respect for the globally dispersed Acacia tree and how
marvellous it is as enhancer of LF signals wrt probes - so perhaps the
trees speak more than we really think at RF...
Laurence
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