[aprssig] RE: Marrying Doppler & APRS

Robert Bruninga bruninga at usna.edu
Mon Mar 20 16:24:25 CST 2006

>>> noskosteve at yahoo.com 03/20/06 5:00 PM >>>
>>  ...  The distance field for a DF line is important 
>>to limit the bearing  lines to only that area of 
>>interest and not infinitly long.
>>   ... This vastly improves the visibility of the maps  ... 
>>otherwise,  an observer looking at a 128 mile range 
>scale map would see total gyberish, 
>  As usual, Bob, a good idea.

Yes, it only took one replay of an event at the wrong
scale to realize that the vectors have to be a length
appropriate to the area of interest as we were circling 
as we  homed in on the fox, or it makes no sense
at other map scales.

With DF vectors limited to the approximate range of
the fox, At the 2 mile scale, you see short vectors directed
INWARD to where the fox is.  But at the 32 mile scale
and with full screen DF vectors, the SAME vectors
appear to be a nonsense bearing line in all directions 
of the compas OUTWARD and the viewer makes no
sense whatsover.

That is why I am so very disappointed that other 
APRS software does not use the standard RANGE SCALE
for all map descriptions to make sure that different
viewers are "on the same page" so to speak when
they are looking at maps!

de WB4APR, Bob

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