> I'm looking at the series combination of four large inductors, and a
relatively small rod.  I know from direct observation that the system is
series resonant near 250kHz, with a low impedance notch.


The mini-NEC antenna modelling program may help.
I've never used it ...

Available many places including here

        http://www.geocities.com/gregsdownloadpage/em.html

He has other interesting related programs too.


        RM

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