Dear all
In all the excitement regarding magnetic direction devices, has anyone
mentioned fluxgate devices with arc-minute accuracy? (specious claim -
indefensible really).
I read Electronics and Wireless World 5 years back now, got the kit and
built one sensitive to micro-gauss for monitoring the earths magnetic field
for incipient aurorae.
The company supplying the coil, Telcon metals, still exists as far as I know
and thus so should the supplier of the kit. It strikes me as being the
perfect thing for a PIC project. What's more it has a follow-up article
using it as the core of an electronic compass. In the kit you use an
oscillator and dividers to drive a square way across a coil and pick the
saturation effects up using orthogonal sense coils on the rising and falling
edges of the excitation wave. To drive it with a PIC and transistor array-
too easy sir. What *and* use an 8 bit ADC to measure the  output signal ?
Given a sufficient kick I may even bother to dig up the reference.
Email me if sufficiently desperate.
Mike
***************************************************************************
M. Harrison                                     TEL 44 1235 445288
Space Science division                          Fax 44 1235 445848
Rutherford Appleton Lab                         email m.c.harrison@rl.ac.uk
Building R25 Room 2.124                         mike@leyenda.demon.co.uk
Chilton
Oxon OX11 0QX UK
***************************************************************************