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[aprssig] Dayton Pilgrimage Mobile Settings

Robert Bruninga bruninga at usna.edu
Thu Apr 19 17:41:34 UTC 2007


Dayton Mobile Settings:

If you like meeting new people on your pilgrimage to Dayton,
here are the recommended settings for 2 VOICE channels.

EVERYONE:  146.52, and 144.39 with CTCSS 100

Monitor 146.52 and find contacts there.  But if NOTHING heard,
then all the rest of the time sit on 144.39 CTCSS 100.  If there
is anyone within simplex range, you automatically will hear a
fractional second tone burst once every minute or so from their
APRS Voice Alert System.  

VOICE ALERT:  This setting for APRS mobiles TX and RX's with
CTCSS 100.  Thus, even though the channel is full of packets,
NONE of them have PL 100 except the direct packet from a nearby
mobile, not all the digipeted copies.  So if you hear a PL100
packet, then you are not only in SIMPLEX range, but the other
station is in-effect "calling CQ" for anyone else running voice
alert to contact him because he has the volume turned up and is
listening with CTCSS 100 just like you.  Just key up, make voice
contact and QSY to 52 (so you are not competing with all the
other packets on the 144.39 channel).

Although only APRS mobiles are Transmitting the PL 100 pings,
everyone else can listen for these "pings" alerting you to their
presence.  Why is this better than 52?  Because it is like an
automatic "CQ 52"  once a minute.  This guarantees you will be
able to make contact even in a passing situation.  On 52, most
contacts are ships passing in the night completely unaware of
each other unless everyone is calling CQ every minute the entire
trip.  In a crossing situation, you are only in simplex range
for about 3 minutes or so (2 miles a minute crossing situation).

By using the automatic APRS Voice Alert system, you can't miss
someone.  Come join us. 

APRS MOBILE SETTINGS FOR DAYTON:  Set your TNC or tracker to the
path of VIA WIDE1-1,WIDE2-1.  This will get you out farther than
you can talk though any voice repeater, and should be
sufficient.  Set your beacon rate to 1 minute or 2 minutes.  No
less.

APRS LAPTOP SETTINGS FOR DAYTON:  First, let someone else drive
so you can spend the 8 hour trip playing APRS like never before.
Use the above path, but also put whatever Voice channel you are
monitoring, make sure that is included in your POSIT PACKET so
that all other APRS mobiles can see what voice repeater you are
monitoring.

SOFTWARE SELECTION AND MILEMARKS:  Make sure you use an APRS
program that fully supports the fundamental milemarks and
Deadreckoning!

MILE-MARKS:  Most mobiles will not have APRS, but ALL of them
will know their position by their milemark.  APRS has a built in
mile-mark system that will allow you to place someone you are in
QSO with on the map by just asking them their mile mark,
entering the route number and mile mark, and BINGO you have
placed a vehicle object on the map at their location.  Assuming
they are headed to Dayton, then you can enter an estimated CSE
and SPEED.  

>From that point on, that CAR and its object will continue to
move on your APRS map toward Dayton and so even without GPS, you
have a good approximation where that person is.  You can AMAZE
him by calling him every half  hour or so and mentioning "I see
you are approaching Crabtown".  "How can you tell that?"
Because I am tracking you with APRS.  "But I don't have APRS".
And you answer.  "But I do"...

MILEMARKS and Dead Reckoning were fundamental to allow APRS to
see the Tactical Situation around them, INCLUDING all stations
participating even if they don't have APRS.  Once you put "joe"
on the map moving to Dayton, ALL OTHER APRS mobiles within 100
miles or more of you will also see JOE on their maps.  And if
they have Dead Reckoning Enabled, then Joe should continue to
move on their maps too.  You can even enter his frequency in his
object text, so that others know what freq to contct him on.  If
joe stops for a rest stop, next time he mentions a milemark,
just click and drag him to the new milemark, and his DR will be
updated on everyone else's map too.

Without Dead Reckoining, the map display of an APRS client is
always wrong.  It always shows where things were 1, 3, 5, 10, 30
minuets ago, which is pretty useless in maintaining "situational
awareness"!!!  Turn on DR going to Dayton!  And USE MILE MARKS
and objects to show us everyone else on the road in range, not
just the APRS folks.  APRS was never desigend to be an
end-in-itself, but to be a tool for ALL OF Amateur Radio.

APRS WITHOUT GPS?!  Sure,  Just hook any-old TNC to your radio
and type in a LAT/LONG posit and CSE and SPEED once eveyr hour
or so.  All surrounding APRS stations with DR turned on, will
see you move on their screens.  Before the trip, just copy down
the approximate lat/long of some key landmarks about every hour
on your route to Dayton.  When you pass one, just type these
into your TNC Btext in APR Sformat. Set yoru beacon rate to once
every 2 minutes and your unproto path to APRS VIA WIDE1-1.  This
will update your position on evrone's map.  And with DR on, you
will continue to move on their maps..

VOICE ALERT WITHOUT APRS?!  Sure, anyone can receive voice alert
just by setting CTCSS on 144.39.  But you can also PING if you
want.  Just load something like ">Joe Enroute Dayton Voice
Alert" into the Btext of any old TNC and set the beacon rate to
once every minute, again with CTCSS 100.  Now all APRS people
will hear you when they get in simplex range of you and may call
you and you both then can go to 52.  Be sure to set your UNPROTO
PATH to "UNPROTO APRS" without any digipeaters, because beyond
simplex range, you are only QRM.

For more details, see this web page:

http://www.ew.usna.edu/~bruninga/VoiceAlert.htm

ALL DIGIPEATER OWNERS:  Make sure your digitpeater has the
proper settings for the New-N paradigm.  For details see:

http://www.ew.usna.edu/~bruninga/aprs/fix14439.html

DIGIS IN DAYTON:  Turn off WIDEn-N support except for ONE HOP.
This whould be able to support 150 APRS mobiles which is typial
of APRS in Dayton.  TO do this (assuming you have set your digi
for New-N above):

1) Set UITRACE to TEMP,30
2) Set UIDIGI ON WIDE1-1

This will cause these digipeaters to digipeat any/all mobiles
ONE HOP and will prevent any outside QRM from coming in.

WATCH FOR RECEOMMENDED VOICE REPEATER FREQUENCEIS ON THE FRONT
PANEL OF YOUR MOBILE APRS RADIO:  Many areas are supporting the
"New Local Info Initiative" which transmits local-direct info on
the recommended voice repeater in their area for direct display
on the D7, D700 and HamHUD mobile Displays.  See:

http://www.ew.usna.edu/~bruninga/localinfo.html

Hope I got everyting covered.  I'll be PASSENGER mobile this
year and will be playing APRS all the way from Maryland to
Dayton on Thursday night and Friday morning.

Bob Bruninga
WB4APR






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