From: WarmSpgs@aol.com
Message-ID: <49.1820cfe.25eed9a7@aol.com>
Date: Wed, 1 Mar 2000 15:37:59 EST
Subject: Re: LF: Re: Low loss inductors
To: rsgb_lf_group@blacksheep.org
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In a message dated 3/1/00 2:29:31 PM Eastern Standard Time,  
computernetworks@excite.com writes:

<< So Q = 1722/4.46 = 386, which is somewhat better than your conventional 
coil. >>

If someone actually performs such a measurement (I hope someone can; math is 
wonderful and theory is indispensible, but the only way to see if theory is 
being applied correctly is to test a hypothesis under controlled, repeatable 
conditions) I think we'll find it to be significantly worse, not better.  For 
one thing, the DC resistance of the center conductor will be found to be 
somewhat greater than 4.46 ohm in practice, and effective resistance at RF is 
invariably higher than for DC.  For another, as I believe Rik ON7YD has 
already pointed out, dielectric loss cannot be dismissed as insignificant at 
these frequencies, considering the lengths of cable involved and the 
additional loss that results from operating under deliberately-induced high 
SWR conditions.

73,
John