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References: <BFF6723B062BFF40B4B7A6CF670160B403129C18@argos2.clb.tcfr.thales> <4B978B2E.70404@iup.uni-heidelberg.de>
Date: Wed, 10 Mar 2010 16:56:26 +0000 (GMT)
From: Dave Pick <davepick@btinternet.com>
To: rsgb_lf_group@blacksheep.org
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Subject: Re: LF: KITE ANT
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Stefan

Just one warning, I have used kite-supported aerials on 136 many times and=
 you have to be careful what insulating material you have between the kite=
 and the top of the wire. One day the kite was flying well but there was=
 a little rain, I transmitted and the wire fell out of the sky and the kit=
e fluttered down (fortunately I could find it!). When I looked to see what=
 had happened the thin rope holding the wire to the kite had burned throug=
h because the rain had made it conductive. I think monofilament fishing li=
ne may be better...

Dave G3YXM



----- Original Message ----
From: Stefan Sch=E4fer <Stefan.Schaefer@iup.uni-heidelberg.de>
To: rsgb_lf_group@blacksheep.org
Sent: Wednesday, 10 March, 2010 12:06:06
Subject: Re: LF: KITE ANT

...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 sti=
ll try to get that permission for the next weeks. Then, the VLF signal wou=
ld 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 yo=
u 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 syst=
ems (http://www.hst.tu-darmstadt.de/index.php?id=3D10&L=3D1) and had almos=
t each week to work with voltages well above 20kV (up to 3MV, 1,2/50=B5s),=
 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 Jean-Louis.RAULT@fr.thalesgroup.com:
> Hi all
>=20
> May I ask you to pay some attention on the three following issues relate=
d to balloon/kite aerials ?
>=20
> - 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)
>=20
> - even when weather is very good, very high DC voltages (many  kV) can=
 appear (from natural local electric field) on the antenna wire. DC ground=
ing of the wire is therefore mandatory
>=20
> - avoid any AC HV lines (or schools, or roads, or irritable neighbours)=
 in the vicinity of your experiment area.
>=20
> Regards
>=20
> Jean-Louis F6AGR
>   =20