Hi all,
    The conclusion of the recent discussion about mu-metal was that after you 
cut it, bend it or whatever, it needs to be annealed in a Hydrogen atmosphere 
to restore its desirable magnetic properties. This is discouraging news for 
those of us who would like to build our own fluxgate sensor for a 
magnetometer. I discussed this with Jack Janicke, author of "the Magnetic 
Measurements Handbook". He has some flat strips of Permalloy-80 he can sell 
you to make your own homemade straight fluxgate. The cost is $4.00 which 
includes shipping and handling. He will include winding instructions and a 
coil form. Expect a week or two delay in shipping while Jack puts this kit 
together and writes the winding instructions, His email address is 
<> His  postal mailing address is:

                        Jack M. Janicke
                        122 Bellevue Avenue
                        Butler, NJ 07405 
                        USA
Have fun,
Cap
            
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In a message dated 6/12/00 11:39:04 PM Eastern Daylight Time, 
ChrisAtUpw@....... writes:
              
<<  The straight fluxgate sensors used to be made from insulated wire to 
 reduce eddy current problems. If you have really thin foil, you could 
 probably just roll up a multi turn coil, but the metal probably wouldn't 
have 
 it's optimal magnetic properties.---------------- Sorry not to be more 
encouraging.------------- I would just try making a core. You would probably 
need more drive field, but so what? ----------------- Several companies 
market fluxgate sensors, but that's not like making your own. >>

       Regards

       Chris Chapman
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