Envelope-to: dave@picks.force9.co.uk
Delivery-date: Sun, 17 Jul 2005 18:47:28 +0100
Disposition-notification-to: ve7alq_lf@shaw.ca
Date: Sun, 17 Jul 2005 10:46:43 -0700
From: "Ya`akov N. Miles" <ve7alq_lf@shaw.ca>
To: rsgb_lf_group@blacksheep.org
Message-id: <42DA9983.9080002@shaw.ca>
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Subject: LF: Apparent Error in "LF Today", g3xdv, formula page 83
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I notice that the book "LF Today" put out by Alex Dennison, g3xdv
appears to have missed a parameter its loop radiation resistance
formula as stated on page 83

Rr = 320 * (pi**4) * A*A/(Wavelength**2)

This equation does not scale with wavelength even if the area  A
is scaled proportionately with the Wavelength.  I believe this should be

Rr = 320 * (pi**4) * A*A/(Wavelength**4)

This can be simplified (for circular loops of diameter D)

Rr = 17228. * ((D/Wavelength)**4)

and this equation gives answers which agree with published data elsewhere.

-- 
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