To: rsgb_lf_group@blacksheep.org
Date: Mon, 8 Mar 2010 14:56:34 -0500
Message-ID: <20100308.145635.644.0.riese-k3djc@juno.com>
MIME-Version: 1.0
From: riese-k3djc@juno.com
Subject: Re: AW: LF: VLF TX coil ready
Content-Type: text/plain; charset=iso-8859-1
Sender: owner-rsgb_lf_group@blacksheep.org
Precedence: bulk
Reply-To: rsgb_lf_group@blacksheep.org
Content-Transfer-Encoding: quoted-printable



Check http://jeff560.tripod.com/loomis.html,, just used ground currents
which may have excited his kite wire,,,,, =20
Bob K3DJC


> =20
> And: Does anybody of the group want to buy such a kite? A second=20
> "kite-station" would give the chance for a 2 way QSO there! Maybe in=20
> good old CW! :-)
> =20
> 73, Stefan/DK7FC
>=20
> ________________________________
>=20
> Von: owner-rsgb_lf_group@blacksheep.org im Auftrag von Paul=20
> Nicholson
> Gesendet: Mo 08.03.2010 07:57
> An: rsgb_lf_group@blacksheep.org
> Betreff: Re: LF: VLF TX coil ready
>=20
>=20
>=20
> Stefan Sch=E4fer schrieb:
>=20
>  > [VLF loading coil] has about 1100 turns. Average diameter is
>  > about 0,55m, hight about 0,5m.
>=20
> I ran this info through a modelling program, with a guess that
> the wire is 26awg:-
>=20
>   Ldc: 482mH
>   Rdc: 258.3 ohms
>=20
> Resonances, unloaded, base grounded, stood vertically 10cm
> above a good ground with nothing within a few metres:-
>=20
>   1/4 wave : 46.56 kHz
>   3/4 wave: 121.7 kHz
>   5/4 wave: 195.5 kHz
>=20
> Adding a 100m kite, 2m diameter, raised vertically (=3D560pF) to
> the model, I found I needed an extra 70pF of shunt loading to
> bring the system into tune.
>=20
> The system resonances then become:
>=20
>   1/4 wave:   8.973 kHz
>   3/4 wave: 116.3 kHz
>   5/4 wave: 185.4 kHz
>=20
> Hopefully you can seal the coil before the thing warms up and
> the turns fall out of place!
>=20
>  > TX power of 200W.
>=20
> I bet you will need more, eg 500W.   Very hard to predict the
> Q factor obtained in the field, but it is always lower than what
> you hope it will be!
> --
> Paul Nicholson
> --
>=20
>=20
>=20
>=20
____________________________________________________________
Home Improvement Projects
Do it right the first time.  Click to find contractors to work on your hom=
e improvement project.
http://thirdpartyoffers.juno.com/TGL2141/c?cp=3DOY3blswFvUGOcdUNHEWzmQAAJ1=
D5rfaR-77IPsUFbn2LcZ2XAAYAAAAAAAAAAAAAAAAAAADNAAAAAAAAAAAAAAAAAAAShAAAAAA=
=3D