Dear Peter, LF group,

I have used a simple DOS program coil.exe (runs OK in windows DOS box) which can be downloaded as coil02.zip from http://www.moshier.net/coildoc.html
with reasonably accurate results for several types of coil. This implements one of several text-book formulae depending on what menu option you chose - it does loops, round and square solenoids, toroids etc. The Decca type basket-weave coil is probably best represented by a multi-layer circular solenoid (option 7). Don't forget to set the dimensions (option 11 - inches or cm).

Do not expect very accurate results with this type of coil - all the formulae ignore distributed capacitance, which makes L frequency dependent. Multi-layer coils are obviously susceptible to this, which makes the apparent inductance higher.

Cheers, Jim Moritz
73 de M0BMU