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[aprssig] [WOTADB] Frequency Reporting by APRS too

Robert Bruninga bruninga at usna.edu
Sat Apr 8 14:20:41 UTC 2006


There is a move afoot by the ARRL to make it
easiler to locate Hams' operating frequencies 
so they can easily be contacted.  One effort,
called WOTA for "who is on the air" is tied into 
logging programs.

But, of course, APRS already has a global system,
so all we have to do is to include our operating 
frequency in our packets if we are actively monitoring 
a voice freq.

In the past, Frequency  has not been particularly
highlighted, but it is very important and useful for
most mobiles because they usually have a live operator
present and usually he is monitoring his favorite
repeater.   We just need to be consistent in how
we report it.

This way, not only can you click on the APRS FINDU 
web page to see where someone is while mobile
(live), you can also see what his voice operating 
frequency is too.  In the future we hope to solidify
this construct so that it can easily be parsed in the
FIND data base too.

For example, see:   http://map.findu.com/we4apr-9 

You will notice my beacon contains the text:

     "147.075MHz & VoiceAlert 14439"

The 147.075 is the local repeater I always monitor,
but the "VoiceAlert 14439" is always guaranteed 
to work, since the APRS side of the radio is always
there and the volume is always up (though squelched
by CTCSS-100).  But he can always be contacted
if within simplex range.

I would like to encourage all APRS mobile operators
that  do consistently monitor a particular frrequency
to please include it in your packet and in the standard
format above so we can build a parsing system to take
full advantage of it.

The format is

FFF.FFFMHz....remainder of position comment text

Notice that this is exactly 10 spaces which is also
perfectly matches the 10 character wide window
on the front panel of the D7 and D700 radios, 
making it a pleasent display of someone else's
operating frequency when it comes in.

Notice how my beacon is also carefully crafted 
to show the Voice Alert info also.  Here is how it
flashes on the D700 panel on recepit:

WE4APR-9:
147.075MHz
-VoiceAlrt
 144.39

On the D7 display only the first two
lines are displayed:

WE4APR-9:
147.075MHz
-VoiceAlrt

Anyway, I would like to encourage everyone to
begin using this format.  If we can standardize
on it, then maybe we can get future radios,
and HAMhuds and other display devices to not
only display this info, but to automatically insert
it into our packets whenever we change the radio
knob.  

Someone even wrote a little PIC device to hang
on the D700 serial port to query the radio's
frequency and then to write it into the radio's
transmitted beacons.  This way, the person's
operating freuqency was always known, even if
he QSY'ed.

For more info on this, please see:

http://www.ew.usna.edu/~bruninga/aprs/freqspec.txt

de Wb4APR, Bob






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