At 08:37 30/06/00 +0100, G4JNT wrote:

There is also the issue of reduced skin depth and extra losses when
using steel wire, or any other magnetic material for that matter.   Skin
depth reduces as the square root of relative permeability, which for
steel wire is several thousand.

Following might be interesting :

Aluminium has a lower conductivity compared to Copper (1.76 lower) but has
a higher skin-depth (on 136kHz : .18mm for Cu, 0.24 for Al).
The result is that for wires with a diameter of more than 1mm Al is only
32% worse than Cu. Or otherwise, a 1.3mm Al wire will have the same losses
as a 1mm Cu wire while the weight of 1.3mm Al wire is only half of 1mm Cu
wire.

73, Rik  ON7YD