Does the A sub L of a ferrite core change at very low signal levels?



Background; Years ago in an electronics class we measured a

5 Henry laminated iron core inductors. We drove it with a low

current 60 hz signal. The whole class came up with an answer of

around .75 Henry. This was a 5 Henry high current inductor.

After some head scratching and looking at B-H curves I decided

it measured low because of the slope of the curve. At low B fields

the curve is horizontal and as B goes up the curve moves more

vertical.

So I'm wondering if the transformers we wind for antennas are

working properly at small signal antenna levels. Is our primary

reactance really 4 times the source impedance at very low signal

levels?



Does the AsubL of a ferrite core change at very low signal levels?



Mike