> Which is the material that will produce the most inductance, handle the most > power safely at 400 to 500 kc/s? > > > Is it the 31 mix you mentioned? I have had very good luck with 31, but my best results so far have been with type "J" material. http://www.amidoncorp.com/ft-193a-jc/ Best DX & 73, Ralph W5JGV - WD2XSH/7