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From: "Soegiono, Gamal" <soegiono@nmex01nt.hsd.utc.com>
To: rsgb_lf_group@blacksheep.org
Subject: LF: capacity of wires
Date: Mon, 28 Jun 1999 07:05:08 +0100
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Hello all,

here some equations which I found in my book
regarding capacity of wires above a ground plane.


vertical wire of diameter d[m] and length l[m]
lower end being h[m] above ground

Cv[pF]=55.6*l / {ln (2*l/d)*SQR[(1+l/(4*h))/(1+3*l/(4*h))]}
restriction: d << l

test:
l=4m h=1m d=2mm
Cv = 37.921 pF



horizontal wire of diameter d[m] and length l[m]
being h[m] above ground

Ch[pF]=55.6*l / {ln (2*l/d)*SQR[(SQR(1+(4*h/l)^2)-1)/(SQR(1+(4*h/l)^2)+1)]}
restriction: d << l

test:
l=2m h=10m d=1mm
Ch = 14.094 pF


Best 73 

Gamal Soegiono (SWL)

50N01 / 08E27 / JO 40 fa
soegiono@nmex01nt.hsd.utc.com