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It seems to me on the the lower frequencies to cover a
reasonable distance of a few hundred kilometres a good Antenna and plenty of RF
power is needed as has been proved by the recent experiments by DK7FC and his
kite antenna, OE5ODL and his balloon antenna and HE3OM with his ex BC
static tower antenna. Also I understand these stations are using amplifiers of a
few hundred watts hence a respectable ERP output.
On VLF es LF especially, using anything but a proper
elevated antenna is wasted time except one is content with a few kilometres
coverage, and earth probe inductive/conduction devices are only good for
Cave Divers.
also
to cover the greatest distances a Vertical and a proper
loading coil to resonate the system is the preferred method to launch the
signal.
I am able to copy OE5ODL and DK7FC on 9 Khz at 1400
kilometres and 800 kilometres respectively using vertical antennas.
No signals heard from UK VLF/LF experimenters so far,
except G3XIZ and G3XDV appear the odd time on 137 Khz
De G3KEV
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