[aprssig] Dfing success on APRS

Robert Bruninga bruninga at usna.edu
Thu Apr 9 14:46:39 EDT 2009


We found the stuck 144.39 transmitter.

To see how APRS helped visualize these signal strength reports
on yesterday's event, please see the web page:
www.aprs.org/dfing.html 

You can see how we were getting close, just by signal reports
alone.

It is a little bit frustrating how difficult it is to get Height
above average terrain information from most hams. Seems many
hams do not understand the difference between HAAT and their
mast-height or their height above sea level.  Neither of which
mean anything.  But  HAAT completely describes their "coverage"
by simply how high their antenna is generally, above the GROUND
in the general area in the direction where we are interested.
It is so simple, but we are failing in our ham education system
to educate operators to this fundamental station parameter (at
VHF and above)...

Worse, some APRS programs even left it out completely!

Please look at the solution on the web page, and encourage your
fellow hams to practice it whenever you get a jammer or unknown
signal.  You don't need APRS, just a map and pencil. (Though
APRS helps estimate the size of the circle based on HAAT and
signal).  Read the rest of the page and you can see how easy it
is to drive right to the source without APRS or any DF
equipment, just your mobile or HT and your grey-matter and
enough time..

Bob, WB4APR





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