The loopstick magnet is not permanently magnetized. Normally we think of BaFe as a hard magnetic material- IOW a PM. That is one of may quandaries in trying to identify what is active about the cores in question. Hard magnets are usually no good as "antennas" but that is not the use here.
BTW This could relate to why the eBay cores were rejects and ended up at a fraction of the expected price. Since DrS has some old BaFe cores from earlier days (MRA etc) which do work, he took the seller's word on the composition. There are also "lesser" BaFe magnets, which can have only small amounts of barium relative to iron. Some of these "can be" soft. This kind of "cheap ferrite" is used in fire extinguishers for instance. As BillB mentioned, a high "Q" is probably important. Jones --- Terry Blanton <[EMAIL PROTECTED]> wrote: > Not magnetic that I am aware. No mention of it in > his web site that I recall. > > Terry > > On 10/20/07, OrionWorks <[EMAIL PROTECTED]> > wrote: > > Is the barium ferrite core used in Dr.S's device a > permanent magnet? > > I'm assuming that's not the case. I'm assuming > there are no permanent > > magnets involved. > > > > Am I right on this? > > > > > > Regards, > > Steven Vincent Johnson > > www.OrionWorks.com > > > > > >
