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LW1DSE > ALL      23.01.10 03:39l 267 Lines 13780 Bytes #999 (0) @ WW
BID : 1041-LW1DSE
Read: GUEST
Subj: APRS PROTOCOL
Path: IZ3LSV<IW0QNL<IK6ZDE<OK0NAG<9A0BBS<VE2PKT<ON0BEL<F1FBB<CX4AE<LW1DRJ<
      LW8DJW
Sent: 100123/0103Z 36705@LW8DJW.#1824.BA.ARG.SA [Lanus Oeste] FBB7.00e $:1041-L
From: LW1DSE@LW8DJW.#1824.BA.ARG.SA
To  : ALL@WW


[ฏฏฏ TST HOST 1.43c, UTC diff:5, Local time: Fri Jan 22 21:16:39 2010 ฎฎฎ]

APRS On-Air Protocols and Formats

APRS and Mic-Encoder are Trademarks of Bob Bruninga
APRS protocols are copyrighted material of Bob Bruninga, WB4APR

         COPYRIGHT 1992-98: Amateur radio operators may freely copy and use
the APRS software in the Amateur Radio Service. I have tried to make APRS
fully capable of receiving and plotting ALL on-the-air packets whether a
station is registered or not. The registration contribution only balances the
headache factor, and to cover myself against un- licensed commercial
exploitation. What you get for registering is the ability to interface your
own GPS/WX/DF units and a little convenience in saving your configuration.

         Amateur Radio operators may apply the APRS formats in the
transmission of position, weather, and status packets from their own station.
However, the author reserves the ownership of these protocols for all
commercial applications and for all reception and plotting applications,
amateur or not. Homegrown versions and/or the release of source code would
cripple further APRS development and the maintenance of on-air standards
leading to chaos and aren't authorized.

         APRS is a registered trademark of APRS Software and Bob Bruninga.
Other software engineers desiring to include APRS protocols in their software
for sale within or outside of the amateur community will require a license
from the author. Licensing isn't intended to be restrictive, but to provide a
means for the maintaining a consistent on-air protocol and for the owner of
APRS to share in any proceeds made from APRS applications.

         APRS uses UI frames which retain all of the error detection
capability of standard packets, but without acknowledgment. In APRS,
collisions or lost packets aren't a problem since information is redundantly
transmitted (AND effeciently! due to the decaying transmission periods). UI
packets are the same type that are sent by a TNC using BEACON and BText
commands. NOTE, however, that the APRS UI packets are generated internally in
the APRS software and the TNC BText isn't used while APRS is running.

         APRS uses the TNC UNPROTO command to setup the path for the trans-
mission of each packet. But when we refer to the UNPROTO command in APRS, we
are refering to the APRS UNPROTO or OPS-UNPROTO command which then in turn
issues the hardware UNPROTO commands to the TNC.

         TO ADDRESS: APRS uses the TO address to indicate the general
application of your packets or to address certain sub-nets of interest. By
default, APRS will accept packets addressed to the following generic calls:

         APRS, BEACON, ID, CQ, QST, BEACON, MAIL, SKYWRN, GPS, DFNET, TEST,
DRILL and SPCL.

         All other TO addresses are ignored unless you set
CONTROLS-FILTERS-OTHER to ON. There is also a alt-SETUP-MODES-SPECIAL command
which tells APRS to ignore ALL TO calls except SPCL. Similarly it configures
your station to transmit TO SPCL. This allows participants in a special event
to ignore all other traffic on frequency but still all non-participants will
still see the SPCL packets. You can also use alt-S-MODES-altNet to set up any
other private alternet address so that your APRS packets don't clutter up
other APRS users screens.

APRS FORMATS: In the following APRS on-air formats, the abbreviations are D
for degrees (or DAY), M for minutes (Both lat/long and time), h for
hundredths (or Hours), N for North and W for West. The APRS symbol is
identified by the character following the Longitude (shown here as a $).
There are three types of time for local, zulu and hhmmss.

POSITION REPORT: The first character determines the position report format
except for the FIXED format which may occur anywhere up to the 24th character
position in the packet. If the posit begins with @ or = then APRS is running.
If only a TNC is running, then a ! or a / indicates that there is no APRS
messaging capability on line. In this case, the date- time means the time
that APRS was last running.

FIXED:      .......!DDMM.hhN/DDDMM.hhW$comments...   (fixed short format)
                   =DDMM.hhN/DDDMM.hhW$comments      (message capable)
            /DDHHMM/DDMM.hhN/DDDMM.hhW$comments...   (no APRS is running)
                                                     (fades gray > 2 hrs)
MOBILE:     @DDHHMM/DDMM.hhN/DDDMM.hhW$CSE/SPD/comments...
DF:         @DDHHMM/DDMM.hhN/DDDMM.hhWCSE/SPD/BRG/NRQ/Comments
            .......z............................. (indicates Zulu date-time)
            ......./............................. (indicates LOCAL date-time)
            .......h............................. (Zulu time in hhmmss)
GRDSQR:     [XXnnyy]comments to end of line
            [XXnn]comments to end of line
W3AB>FM19SX:Hello there....                       (Space/MScat/Grid-SQ mode)
W3AB>FM19SX:]$[Hi there....                       (Space/MScat with stn symbol
POWER:      ..........................$PHGabcd... (Power,ant/height/Gain.

OMNI-DF: ..........................DFSxbcd... (Same as PHG, but x=sig str)
RTTY: APRS DE WB4APRx/011427/3859.11'07629.11($ ... This format uses only the
RTTY subset of the ASCII alphabet where ',)( mean N,S,E & W, and the x is an
SSID number and the $ is the APRS symbol character. The ... comment field can
contain the normal APRS CSE/SPD. The callsign must be padded to six spaces.

POWER-HEIGHT-GAIN: This optional field replaces the CSE/SPD fields with a
report of transmitter power, antenna height-above-average-terain and antenna
gain. APRS uses this to plot radio range circles around all stations. The
following details the format to be used in the BText of a TNC dedicated as an
APRS digipeater:

!DDMM.mmN/DDDMM.mmW#PHG5360/WIDE...(identifying comments)
 | | | | |||| |_____ makes station show up green
 | | | | ||||________ Omni (Direction of maxgain)
 | | | | |||_________ Ant gain in dB
 | | | | ||__________ Height = log2(HAAT/10) LAT LONG
 | | |___________ Power = SQR(P)
 | |_____________ Power-Height-Gain identifier *
 |_______________ # is symbol for digipeater

         As you can see by the integers in the PHG string, there are only 10
possible values for each of these fields as follows:

DIGITS 0 1 2 3 4 5 6 7 8 9 Equation
-------------------------------------------------------------------
POWER 0, 1, 4, 9, 16, 25, 36, 49, 64, 81 watts SQR(P)
HEIGHT 10,20,40, 80,160,320,640,1280,2560,5120 feet LOG2(H/10)
GAIN 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 dB
DIR 0,45,90,135,180,225,270, 315, 360,. deg (D/45)

         The DIRECTIVITY field offsets the PHG circle by one third in the
indicated direction. This means a front to back range of 2 to 1. Most often
this is used to indicate a favored direction or a null even though an OMNI
antenna is at the site. Note that 0 means OMNI and 8 means 360 or a NORTH
offset.

         HIGHTS are ABOVE-AVERAGE TERRAIN! Not above ground or sea level.
Your antenna may be at 1000 ft above sealevel and be on a 100 foot tower. But
if you go out 10 miles in all directions and find that the average elevation
is 1200 feet, then your height-above-averag-terain is less than ZERO!!!!

         OMNI-SIGNAL-STRENGTH DIRECTION FINDING REPORT: APRS can localize
jammers by plotting the overlapping signal strength contours of all stations
hearing the signal. This OMNI-DF format replaces the PHG format with DFS to
indicate DF Signal strength, and the transmitter power field is replaced with
the relative signal from 0 to 9. The following beacon would represent a weak
signal heard on an antenna with 3 dB gain at 40 feet:

@141923/3859.11N/07629.23WDFS2230/comments

         A signal of ZERO (0), is equally SIGNIFICANT beacuse APRS uses these
0 signal reports to draw BLACK circles where the jammer isn't! These BLACK
circles are extremely valuable since you will get a lot more reports from
stations that don't hear the jammer than from those that do. This quickly
eliminates a LOT of territory!

WEATHER REPORT: APRS uses the underline symbol character for WX reports. For
these, the COURSE/SPEED field is used for the WIND and the remainder of the
comment line contains other weather items.

@DDHHMM/DDMM.hhN/DDDMM.hhW_CSE/SPDgXXXtXXXrXXXpXXXPXXXhXXbXXXXXdU2k

r is in hundredths of an inch of rain in the LAST HOUR
p is in hundredths of an inch of rain in the LAST 24 HOURS
s is INCHES of snow in the last 24 hours b is in tenths of millibars
h is percent humidity (00=100%)
dU2k is Ultimeter 2000,
/U5 is the 500 and /Dvs is Davis
The "d" means it is running DOS

         OBJECT POSITION: OBJECT reports are identical to POSITs except that
the posit is preceeded with a fixed nine character object name and a *.

OBJECT___*DDHHMM/DDMM.hhN/DDDMM.hhW$CSE/SPD/comments...

STATUS PACKET: These packets are used to tell the world your current mission
or any other single line announcement. Mobiles may indicate their destination
and ETA. These packets are time stamped so the sender knows when they were
valid.

>DDHHMM/comments

ALL OTHER PACKETS: Any packet that does NOT meet any of the above formats is
assumed to be just a STATUS beacon and is placed on the LATEST list.

CQ anyone out there?

MESSAGE: Station to station messages use the following format, again padding
the addressee call with spaces to a total of nine characters followed by a
colon:

W3XYZ____:one line message text......{3 (the {3 is the line counter)

MSG ACK: An ACK is just a message with the letters ACK# where the # is the
message line number (following the { character at the end of the line).

W3XYZ____:ack3

BULLETINS: BULLETINs are simply messages to the call signs of BLN1, BLN2,
... BLN#. They will never be acked, but all APRS stations will capture and
sort them onto the special BULLETINS page. Bulletins sent to BLN# will decay
to very long periods but bulletins sent to BLNx will decay down to once every
20 minutes and stay at that rate.

DF REPORTS: The DF report includes a NRQ field in addition to the position,
course and speed of the vehicle plus the bearing line.

@DDHHMM.xxN/DDDMM.xxW\CSE/SPD/BRG/NRQ/DF report...

NRQ indicates the Number of hits (for an N7LUE interface), the approximate
Range and the Quality of the report. If N is 0, then it means nothing. Values
from 1 to 8 give an indication of the number of hits per period relative to
the length of the time period. So 8 means 100% of all samples possible, got
a hit. The N isn't processed, but is just another indicator from the
automatic DF units. By entering a 9 as the HIT indicator, you can indicate to
other users that your report is manual. The range limits the length of the
line to the original maps scale of the sending station. The range is 2^R so,
for R=4 would be 16 miles.

DIGIPEATERS, NODES, BBS's AND ALL OTHER PACKET STATIONS:

         APRS should be used as a generalized position displaying tool, EVERY
TNC that is permanently on the air, and that also transmits a periodic ID
beacon, should be reporting its position in that ID beacon! This way,
stations monitoring can quickly see a geographical plot of the network. If
you want to keep the exact location of your transmitter ambiguous, then use
the GRID-SQUARE format, and your position will be ambiguous to a few miles,
but stations can still see that you are on the air. If you have special
formats for your BEACONS that contain variable information, then APRS is
perfect for grabbing that information and making it available to users...
If you have any unused aliases, set one to RELAY so others can find you.

QUERIES: There are two types of APRS Queries. One is general to all stations
and the other is in a message format to a single station:

?APRS? Queries all stations (respond in 2 mins)
?APRS?LLLLLL,OOOOOO,RRRR Queries a radius around a LAT/LONG point
If RRR is less than 8 then respond immediately
?WX?             Queries all WX stations
W3ABC____:?APRS? Queries just W3ABC (all of his data)
W3ABC____:?APRSP Queries for W3ABC's Posit
W3ABC____:?APRSS Queries for W3ABC's Status
W3ABC____:?APRSM Queries for W3ABC's messages
W3ABC____:?APRSO Queries for W3ABC's Objects
W3ABC____:?APRSD Queries for stations heard DIRECT by W3ABC
W3ABC____:?APRSH W4XYZ Queries to see if W3ABC has heard W4XYZ

W3ABC sends back a packet with W4XYZ as an OBJ and sends back a message with
the number of packets heard per hour from him.

W3ABC responds with his Posit, Status, Messages or Objects as appropriate.
For the APRSD he responds with a single MESSAGE back to the query station as
follows: Directs= N3ABC W4XYZ AB3GH N5QSO ...

In the cse of the ?APRSH query, W3ABC sends back the POSIT of W4XYZ as an
OBJECT and sends back a single line message as follows:

Hrd: 14 15 4 . 10 6 7 .

which are his Heard statistics per hour for the last 18 hours.
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บ      Compilled  from  Internet  .  Translatted to ASCII by LW1DSE Osvaldo  บ   F. Zappacosta. Barrio Garay, Almirante Brown, Buenos Aires, Argentina.   บ
บ      Made with MSDOS 7.10's Text Editor (edit.com) in my AMD's 80486.      บ
บ                            January 21 2010                                 บ
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บ Osvaldo F. Zappacosta. Barrio Garay (GF05tg) Alte. Brown, Bs As, Argentina.บ
บ Mother UMC ๆPC:AMD486@120MHz 32MbRAM HD SCSI 4.1Gb MSDOS 7.10 TSTHOST1.43C บ
บ                 Baterกa 12V 160AH. 6 paneles solares 10W.                  บ
บ                 oszappa@yahoo.com ; oszappa@gmail.com                      บ
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