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Message-ID: <3.0.1.16.20011030093531.2cb76306@mail.cc.kuleuven.ac.be>
Date: Tue, 30 Oct 2001 09:35:31
To: rsgb_lf_group@blacksheep.org
From: "Rik Strobbe" <rik.strobbe@fys.kuleuven.ac.be>
Subject: Re: LF: Decca Coils
In-reply-to: <002501c160d0$873758e0$a1ca28c3@ericadodd>
References: <2614258.1004295195891.JavaMail.computernetworks@gomailjtp05> <3.0.1.16.20011029161314.30eff79c@mail.cc.kuleuven.ac.be>
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At 23:21 29/10/01 -0000, you wrote:
>Hi Rik
>
>> L = inductance (nH)
>> N = windings
>> D = average coil diameter (cm)
>> H = coil length (cm)
>> C = thickness of the wirelayers (all together, in cm)
>> K = correction factor depending on H/C ratio :
>> L/C K
>> 2 0.10
>> 3 0.15
>> 5 0.23
>> 10 0.27
>> 15 0.30
>> 20 0.31
>> 30 0.32
>>
>> 2. For 'fat' coils (H<=D) : L = 78*L^2*D/(3*D+9*H+10*C)
>
>I will use the 'fat' coil formula because with my coil D = 60cm and H =
>18.2cm
>
>I don't understand the L^2 in the formula because L is what I am trying to
>find.

Hello Peter,

My mistake, it should be N^2 instead so : L = 78*N^2*D/(3*D+9*H+10*C)
where 
L = inductance (nH)
N = number of turns
D = average coil diameter (cm)
H = coil length (cm)
C = thickness of all the wirelayers (cm)

BTW : according to this book (Taschenbuch der Hochfrequenztechnik) a 'fat'
coil is more sensible to the enviorement than a slim coil

73, Rik  ON7YD