Message-ID: <003101c1664d$23eaf440$e7c928c3@ericadodd>
From: "g3ldo" <g3ldo@ukonline.co.uk>
To: rsgb_lf_group@blacksheep.org
References: <E15ysc1-0004SW-00@gemini.herts.ac.uk>
Subject: Re: LF: Multi-layer loading coils
Date: Mon, 5 Nov 2001 22:55:57 -0000
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 Dear James, LF group,

>
> In the end, I just used the wire from the Decca coil and scrapped
> the rest. As a former, I found a "sectional manhole" made by Osma
> was very suitable. This is a brown PVC cylinder about 500mm
> diameter and 350mm long, with external ribs. It is meant to form the
> walls of manholes for drains, and several sections can be slotted
> together for a bigger former if needed.

I found one of these Osma 'sectional manhole' units at the local builders
yard - they seem ideal LF coil formers and I wondered how I had missed them
before. I had hunted around all sorts of DIY and builders yards in the past.
>
> About 6 turns of the Decca litz wire fit between each pair of ribs,
> forming a winding 3 layers deep by 2 long. about 80 or so turns
> altogether gave me the required inductance, which has a Q of
> about 700.

What was the inductance of your 80 turn coil?

>. I am using a
> second sectional manhole wound with more turns of smaller,
> ordinary stranded wire for 73k, which stacks on top of the 136k
> loading coil.

can you give details of the second coil?

Regards,
Peter, G3LDO

e-mail <g3ldo@ukonline.co.uk>

Web <http://web.ukonline.co.uk/g3ldo>