Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!uunet!mcsun!ukc!inmos!cheetah!kevin
From: kevin@cheetah.inmos.co.uk (Kevin Cameron)
Newsgroups: sci.electronics
Subject: Re: Hall Effect Sensor
Message-ID: <16869@ganymede.inmos.co.uk>
Date: 25 Jun 91 09:29:15 GMT
References: <1991Jun24.232559.3004@helios.physics.utoronto.ca>
Sender: news@inmos.co.uk
Organization: INMOS Limited, Bristol, UK
Lines: 25

|> keving@cheetah.inmos.co.uk  (Kevin Cameron) writes:
|> Followup-To: Hall Effect Sensor
|> >I always wanted to build a Hall-effect compass - but never got round to it.
|> 
|>    This is not the way to go. The Hall effect is not strong enough to
      ^^^^^^^^^^^^^^^^^^^^^^^^^^
|>the regime of interest. You can buy packaged fluxgate magnetometers the
|> the magnetic field strength along each axis, for about $3000. That
                                                          ^^^^^
|>  Christopher Neufeld....Just a graduate student  | If ignorance is bliss

I'm sure you're right about it working, but $3000 seems a bit expensive
compared to an ordinary magnetic compass. You could probably buy a global
positioning system for that price (Inmos have developed a pocket one based
on transputers).

It only needs to be accurate to ~1 degree to be competitive with a
magnetic compass on performance, but it would need to cost nearer $100
in total to be worth buying instead.

How strong is the Earth's magnetic field anyway?

-------------------------------------------------------------------------------
Kevin Cameron         INMOS, 1000 Aztec West, Almondsbury, Bristol BS12 4SQ, UK
kevin@inmos.co.uk     Tel: (UK) 0454 616 616 x364, Fax: 617 910