In a message dated 3/1/00 2:29:31 PM Eastern Standard Time,
[email protected] 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
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