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From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <NKEMLGOEKANPNJOBFBAFMEKNCNAA.g4wgt@tiscali.co.uk>
Date: Wed, 5 Jul 2006 19:25:04 +0100
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Subject: LF: Re: LF loading coils
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Hi Gary, taken simply I would guess the answer is "NO". The loss in the coil
is but a small portion of the total loss in the system. Several years ago
Dave G3YXM, did an experiment with three old loading coils wound, I believe,
at different stages of his LF transmitting "career". From memory the "worst"
was 1mm plastic covered wire and the best was using thick ex-Decca litz
wire. Dave probably still has the original data, but from memory there was
about a 30% difference in coil loss between the two (9 ohms down to 6 ohms)
As even with Dave's big top-load wires his Marconi has a ground loss of
about 30 ohms, the difference between the coils in the aerial system was a
disappointing 10% , a fraction of a dB, and almost imperceptible to the
receiving station.

I think If you cannot get topload in the only way to improve things is to go
very much higher. I think Steve, GW3ALG's site is still open and there is a
description of his balloon aided vertical, using party helium balloons to
extent his 10m vertical by another 10m. This was only usable when the
evenings were calm.
http://www.alg.demon.co.uk/radio/136/intro.htm
Steve unfortunately left LF when what he described as a "repeater" was
installed as a remote receiver to aid some stations with high levels of
domestic interference  on LF.


----- Original Message -----
From: Gary - G4WGT <g4wgt@tiscali.co.uk>
To: LF (Rsgb LF Group) <rsgb_lf_group@blacksheep.org>
Cc: LW Wave <lowfer@lwca.org>
Sent: 05 July 2006 18:38
Subject: LF: LF loading coils


> Hi All,
>
> There is a lot of discussion at the moment on LF & LW regarding antenna
> tuning & loading etc, I have a related question.
>
> Would there be any noticeable improvement to the performance my 14 metre
> vertical antenna if I replace my normally wound LF loading coils with
basket
> weave coils?
>
> My back garden is so small I cannot run any substantial capacitive top
load
> so I need to improve the antenna system in any way I can.
>
> 73
>
> Gary - G4WGT.
>