Stan Zurek, Approximation of Grover's T(x) function - auxiliary data, Encyclopedia Magnetica,
http://e-magnetica.pl/doku.php/calculator/approximation_of_grover_tx, {accessed: 2025-03-14}
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[1] Frederick W. Grover, Inductance Calculations: Working Formulas and Tables, ISA, New York, 1982, ISBN 0876645570
[2] B.C. Wadell, Transmission Line Design Handbook, Artech House, Norwood, 1991, ISBN 0890064369
Table 52 in [1]
x T(x) approx. by Wadell [2]
TW(x) =
√[ (0.873011+0.00186128*x) / (1-0.278381*x+0.127964*x2) ] 		Wadell's approx. Wadell with Zurek's correction
TW,Z(x) = TW(x) + 0.06/(x+1)6
(published here only)
0 1.0000 0.9344 0.9944
0.5 0.9998 0.9894 0.9946
0.6 0.9997 0.9972 1.0008
0.8 0.9989 1.0089 1.0106
1 0.9974 1.0148 1.0157
1.5 0.9871 1.0031 1.0034
2 0.9611 0.9581 0.9582
3 0.8452 0.8169 0.8169
4 0.6863 0.6747 0.6747
5 0.5560 0.5606 0.5606
10 0.2816 0.2845 0.2845
15 0.1947 0.1875 0.1875
20 0.1413 0.1397 0.1397
50 0.0566 0.0561 0.0561
80 0.0354 0.0358 0.0358
100 0.0283 0.0291 0.0291

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