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RE: Re: "Precision" Antenna Pointing

>Ok, so what to do with Az.  Well, that's a little more complicated, but
>there still might be a digital solution.  They make digital solid state
>"fluxgate" compasses.  Again, an ADC to a micro and you are done.  There is
>one problem with any compass, it's influenced by conductive materials or in
>most cases, large hunks of metal, you know towers, tripods, etc.

There's also magnetic variation, which changes over time, so you'll have to
recalibrate the system from time to time .. but yes, a magnetometer is a
pretty direct measurement, and as long as you compensate for local field
anomalies (which may be large) you can get a pretty decent bearing.  You
could use an optical encoder ring for azimuth and reference it to the
magnetometer though, or take your GPS to a TV tower a few miles away and do
some trigonometry to get a known azimuth fix ..

"Orthodoxy is orthodoxy because it won, not because it is true." -- Bp.
John Spong
 "Power takes as ingratitude the writhing of its victims." -- Rabindranath
               --... ...-- -.. . -. ..... ...- -...
         Bruce Bostwick  mailto:lihan@ccwf.cc.utexas.edu
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