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Old April 17th 06, 11:43 AM posted to rec.radio.amateur.antenna
Owen Duffy
 
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On Mon, 17 Apr 2006 08:41:36 +0100, "Reg Edwards"
wrote:

You dim witts are calculating Q incorrectly.


Reg, that is just so polite!

Q = X / R

where R is the RF resistance of the conductor and X is the reactance
of the conductor's inductance. You first have to calculate
inductance.


So, you state that the ratio X/R is an acceptable way to express the Q
of an inductor, why is it unacceptable to express the Q of a two
terminal device with an equivalent series impedance of 0.88+j50 (where
0.88 is the RF series resistance of the network and 50 is the series
inductive reactance of the element) as 50/0.88 or 57?

Aren't the effiency implications (for that was the context) for a 50
ohm reactance created with a TL stub as described just the same as for
a coil with 50 ohms of inductive reactance and 0.88 ohms of series
(RF) resistance, ie a coil with the same Q factor?

Owen
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