...In Germany you can use a maximum braid length of 100m without a
special licence. If 200m would be allowed, my vertical would be a 200m ;-)
But with a special permission you can relatively easy go up to 300m! I
still try to get that permission for the next weeks. Then, the VLF
signal would even be more than 10dB stronger, what would give the chance
for the UK to get the VLF signal, i hope so...
Static HV dangers are well known to all of us i assume. But the upper kV
range is nothing mystic. 10kV is just a factor 10 of 1kV, just like 10V
is a factor 10 of 1V. You can die if you touch a 10kV power line or if
you touch a 100kV power line. So there is just that rule: Do not touch
when under voltage and assure that there can be no voltage when you
think that there is no voltage (measuring, earthing during operating).
I've worked almost 6 years in the HV group of the institute of
electrical energy systems
(http://www.hst.tu-darmstadt.de/index.php?id=10&L=1) and had almost each
week to work with voltages well above 20kV (up to 3MV, 1,2/50µs), so i
think i have the necessary respect without beeing afraid or careless. On
my hill there are no schools, no roads and no neighbours but i will keep
in mind what you caution on! :-)
73, Stefan/DK7FC
Am 10.03.2010 09:16, schrieb [email protected]:
Hi all
May I ask you to pay some attention on the three following issues related to
balloon/kite aerials ?
- using "high" altitude kites or balloons is often subject to a formal
authorization (at least in France, and specially if you expect to use the aerial close to
an airfield)
- even when weather is very good, very high DC voltages (many kV) can appear
(from natural local electric field) on the antenna wire. DC grounding of the
wire is therefore mandatory
- avoid any AC HV lines (or schools, or roads, or irritable neighbours) in the
vicinity of your experiment area.
Regards
Jean-Louis F6AGR
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