Richard Fry wrote:
"This R is a little lower than the first number I posted--which I looked
up in Kraus, 3rd edition."
An excellent source for everything about antennas, I think. I chose
Arnold B. Bailey who has a special affinity for loops, I think. In "TV
and Other Receiving Antennas" on page 403 Bailey says:
"The small loop has a very low resistance (not much over 0.5 ohm for a
circumference of 0.25 wavelength) and a very high positive Q indicating
inductive reactance. The Q will depend on the thickness of the cross
section of the conductor (P factor, as previously used for rod
antennas). For 200-Mc balanced circular loops, where L=0.25 wavelength
(coil diameter=0.25 wavelength/pi), the following Q`s are
representative:
1. For 1-inch diameter rods, QA = 175
2. For 1/4-inch diameter rods, QA = 280
3. For No. 10 wire, QA = 400."
Bandwidth is about equal to 2/QA.
Q is about X/R, or X is about RQ.
The loop radiation resistance of 0.5 ohm is so small that loss
resistance likely may affect the actual loop resistance total.
I`ll leave the reactance (RQ) for the user to calculate for whatever
frequency and Q may interest him.
Best regards, Richard Harrison, KB5WZI
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