[Xastir] RDF Units?

[Curt Mills]

I haven't messed with direction-finding for quite some time.  I
built portable quads and the double-ducky direction finder way back
when, but always had my eye on the doppler systems ever since I saw
the first one in QST back in, what, '78 or so?  The DoppleScant.

More recently I was checking out the Montreal Doppler-II, and I see
there's a Montreal-I, II, and III now.  I can't even tell which
one's the current (latest) project.

Anyone playing with RDF Doppler units and/or keeping up with the
latest offerings out there?  I'm interested in kit form or
readily-assembled yet inexpensive products.  I need something that
puts out a beam heading on a serial port.  This is for a SAR
project.

If someone can point me to a theory of operation for decoding the
audio signal to come up with a bearing, that would be of interest as
well.  If it's a relatively simple sort of operation (and it must be
since people are doing it with a PIC), then it might be fun to do
that myself someday.  Any open-source RDF Doppler projects out there
I can glean stuff from? 

-- 
Curt, WE7U.				archer at eskimo dot com
http://www.eskimo.com/~archer
  Lotto:  A tax on people who are bad at math. - unknown
Windows:  Microsoft's tax on computer illiterates. - WE7U.
The world DOES revolve around me:  I picked the coordinate system!"