"K7ITM" wrote in message
...

I had no particular interest in looking at the B-H curves, since it's
distortion in filters I'm interested in, and that's easy for me to
test directly.

Looking at the B-H curves will save you the trouble of testing core material
that is obviously non-linear. If the B-H curve is perfectly linear there
would be no distortion in the signals. Some material from just a quick look
at the curves would eliminate them from consideration without the time
wasted testing them.

http://www.ferroxcube.com/appl/info/3B46.pdf


With respect to flux density: there seems to be a bit of a disconnect
between what I know and what you've written. From Faraday's law of
magnetic induction, I expect that for the same inductance with fewer
turns, the flux density must be higher: if the inductance is the
same, the voltage must be the same for a given current at the test
frequency. The same voltage with fewer turns around the same cross-
section core implies higher flux density. No?

With all things being equal that's true, however not all core material
reacts the same. As you can see from the link above things are a bit more
complex than they at first appear. Somebody could do a PhD thesis on the
subject of designing low distortion magnetic components.

http://info.ee.surrey.ac.uk/Workshop/advice/coils/mu/


So far, my tests suggest that you can't draw any conclusions one way
or the other from only the relative permeability of the core
material.

I think it's worth another look myself.


--
Regards,
Leland C. Scott
KC8LDO