Useful App note (15 pages ) on resistance of windings on toroidal cores from MicroMetals. Charts and equations for Rac/Rdc, etc.
FairRite Products Corp catalog http://www.lodestonepacific.com/distrib/pdfs/FairRite/fair_rite_14th.pdf
Lodestone Pacific actually has a lot of useful stuff on their web site ( http://www.lodestonepacific.com/)
Some stuff from Michael Ellis on Directional couplers using toroidal transformers http://members.tripod.com/michaelgellis/direct.html
radio/toroid.htm - 6 Jan 2003 - Jim Lux
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