On Sun, 05 Mar 2006 22:31:05 GMT, "Frank"
wrote:

Dan, I think #43 is powdered iron, which is fine for high Q inductors, but

Type 43 is a nickel zinc ferrite. Spec sheets indicate it is
principally a suppression material, but usable for broadband
transformers up to 10MHz.

Bifilar winding, and possibly better material are probably the key to
improving the transformer, or alternatively making a common mode
choke.

Owen

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