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gps.conf - APRS and GPS Setup and Configuration

The APRS network allows display and/or tracking of the location of an Amateur Radio Station.

APRS operation requires the station to obtain an APRS network password. This may be accomplished using the web page provided to Allstar Link users (see the Allstar Link Web Portal under 'server/Get APRS Password'). Otherwise, passwords may be obtained from other locations on the Internet.

The configuration file that deals with APRS and GPS is /etc/asterisk/gps.conf,
and is specified as follows:

; Configuration for app_gps
;
[general]

call = w6abc-1   ; callsign (including SSID) for APRS purposes
password = 12345 ; Password for APRS-IS server for above callsign
comment = AllStar Node 1999 ; Text to be displayed associated with this station
server = rotate.aprs2.net  ; APRS-IS server to report information to
port = 14580 ; port on server to send data
interval = 600 ; Beacon interval in seconds
icon = r  ; A CAR (default)   Icon do be displayed for station on APRS display (see below)
comport = /dev/ttyS0  ; Serial port for GPS receiver (specify this only if using GPS receiver)
baudrate = 4800  ; Baud rate for GPS receiver (specify this only if using GPS receiver)
;debug = y ; set this for debug output
freq=145.000  ; Display Frequency of station
tone=100.0    ; CTCSS tone of station (0.0 for none)
lat=12.3456   ; Fixed (default) latitude in decimal degrees
lon=-123.4567 ; Fixed (default) longitude in decimal degrees
elev=123.4    ; Elevation of Antenna in Meters (*NOT* HAAT)
power=1       ; Power level (see below)
height=2      ; Antenna Height in HAAT (see below)
gain=3        ; Antenna Gain (see below)
dir=0         ; Antenna Direction (see below)

If you do not have a GPS receiver, DO NOT specify the "comport" or "baudrate" parameters (omit them entirely, do not specify them as blank).

Without a GPS receiver, or if the GPS receiver is not responding (times-out), the "fixed" coordinates and elevation (the "lat", "lon" and "elev" parameters) will be sent as the station's location. This allows for a stationary station to still report its existence and location, and also, still allows a station with a failed GPS receiver to send some sort of pertinent location data.

The encoding of the "power", "height", "gain" and "dir" are each specified as a single digit as follows:

     DIGITS   0  1  2   3   4   5   6    7    8    9
     -------------------------------------------------------------------
     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   omni,45,90,135,180,225,270, 315, 360,   .  deg    (D/45)

The "icon" field is specified as a single character as follows:

NOTE: Since the semicolon (';') is recognized by the
Asterisk config subsystem as a comment, we use the
question-mark ('?') instead when we want to specify
a 'portable tent'.


! - 3 vert bars (EMERGENCY)
" - RAIN
# - DIGI

$ - SUN (always yellow)
% - DX CLUSTER
& - HF GATEway
' - AIRCRAFT (small)
( - CLOUDY
) - Hump
* - SNOW
+ - Cross
, - reverse L shape

- - QTH
. - X
/ - Dot
0-9 Numerial Boxes
: - FIRE
? - Portable tent (note different then standard ';')
< - Advisory flag
= - RAILROAD ENGINE
> - CAR (SSID-9)

@ - HURRICANE or tropical storm
A - reserved
B - Blowing Snow  (also BBS)
C - reserved
D - Drizzle
E - Smoke
F - Freezing rain
G - Snow Shower
H - Haze

I - Rain Shower   (Also TCP-IP)
J - Lightening
K - School
L - Lighthouse
M - MacAPRS
N - Navigation Buoy
O - BALLOON
P - Police
Q - QUAKE

R - RECREATIONAL VEHICLE
S - Space/Satellite
T - THUNDERSTORM
U - BUS
V - VORTAC Nav Aid
W - National WX Service Site
X - HELO  (SSID-5)
Y - YACHT (sail SSID-6)
Z - UNIX X-APRS

[ - RUNNER
\ - TRIANGLE   (DF)
] - BOX with X (PBBS's)
^ - LARGE AIRCRAFT
_ - WEATHER SURFACE CONDITIONS (always blue)
` - Satellite Ground Station
a - AMBULANCE
b - BIKE
c - DX spot by callsign

d - Dual Garage (Fire dept)
e - SLEET
f - FIRE TRUCK
g - GALE FLAGS
h - HOSPITAL
i - IOTA (islands on the air)
j - JEEP (SSID-12)
k - TRUCK (SSID-14)
l - AREAS (box,circle,line,triangle) See below

m - MILEPOST (box displays 2 letters if in {35})
n - small triangle
o - small circle
p - PARTLY CLOUDY
q - GRID SQUARE (4 digit.  Not shown below 128 miles)
r - ANTENNA
s - SHIP (pwr boat SSID-8)
t - TORNADO
u - TRUCK (18 wheeler)

v - VAN (SSID-15)
w - FLOODING(water)
x - diamond (NODE)
y - YAGI @ QTH
z - WinAPRS
{ - FOG
| - reserved (Stream Switch)
} - diamond
~ - reserved (Stream Switch)

When APRS is active on an app_rpt server, the GPS information (either "fixed" (default) or real-time
(as obtained from a GPS receiver)) is conveyed to the chan_echolink driver (for the purpose of accurate
location reporting on the Echolink Network) and to app_rpt so that the latitude, longitude and elevation
may be queried over the air.

GPS derived from RTCM or voter board

To derive GPS information from the GPS on an RTCM called "north" just add ",gpsid=north" to one of the RTCM definition lines in voter.conf and add a matching stanza to gps.conf as in the following example.
The result will be found in /tmp/gps_north.dat and if you want to have that reported on the air by touch tone command then do a symbolic link in the /tmp directory for gps.dat to point to gps_north.dat with the shell command line "ln -s /tmp/gps_north.dat gps.dat"

[north]
call = WZ9ABC-2
password = 12345   ; Password for APRS-IS server for above callsign
ehlert = y
interval = 610
icon = r
comment = AllStarLink Voter North Site
freq=440.000  ; Display Frequency of station
tone=107.2    ; CTCSS tone of station (0.0 for none)
lat=40.100    ; Fixed (default) latitude in decimal degrees
lon=-89.100   ; Fixed (default) longitude in decimal degrees
elev=100      ; Elevation of Antenna in Meters (*NOT* HAAT)
power=9       ; Power level 
height=5      ; Antenna Height in HAAT 
gain=8        ; Antenna Gain 
dir=0         ; Antenna Direction 

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