Re: AC wire resistance with proximitry effects

Original poster: "Barton B. Anderson" <bartb@xxxxxxxxxxxxxxxx>

Hi all,

I measured a few coils today, and a couple which are far outside the norm.

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8.4375" x 39.75", 1789 turns, 24 awg, Loaded with 9" x 30" toroid.

Freq = 73400 Hz.
Q meas = 183.5
Q Fraga = 218.09
Error = 15.86% (better than I thought it would be with a loaded coil)

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4.5385" x 21.165", 900 turns, 24 awg. Bare coil with h/d of 4.4

Freq = 406000 Hz
Q meas = 270
Q Fraga = 251.86
Error = 6.72%

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1.6837" x 54.25" (Seibt coil), 2410 turns, 24 awg. Bare coil with h/d of 32.2

Freq = 600000 Hz
Q meas = 100
Q Fraga = 138.27
Error = 27.68%
Q measurement accuracy difficult due to digital frequency readout is limited.

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12.9" x 9.375", 215 turns, 18 awg. Bare coil with h/d of 0.7

Freq = 388000 Hz
Q meas = 194
Q Fraga = 479.28
Error = 59.52%
Q measurement accuracy difficult due to digital frequency readout is limited.