APRS-tools

The Automated Packet Reporting System (APRS) is a packet radio mode for amateur operators that enables the transmission and reception of location, weather, alerts, bulletins, messages and other data through digitally encoded signals, predominantly on the VHF bands.

aprs-tools is a small collection of scripts that enable cli input and output from the Automatic Packet Reporting System-Internet Service (APRS-IS). Functions include: (1) enabling a station to send a message via an APRS-IS server directly to another station; (2) querying a station for its latest location and other station data; and (3) querying a station's most recent 10 messages.

Installation

Requires Python 3. See requirements.txt for other dependencies.

Using git:

cd
git clone https://github.com/rycolos/aprs-tools.git
cd aprs-tools

Using wget:

cd
wget https://github.com/rycolos/aprs-tools/archive/refs/heads/main.zip
unzip main.zip
cd aprs-tools

Install dependencies:

pip3 install -r requirements.txt

Configuration

Rename config.yaml.template to config.yaml and add the relevant values.

• callsign - Your station callsign. Used as the sending station in aprs_sender.
• aprs_passcode - Your stations' APRS-IS passcode. See https://apps.magicbug.co.uk/passcode/ to generate a passcode if you do not have one already. Used in aprs_sender.
• server_host - Your local APRS-IS server. See http://www.aprs-is.net/APRSServers.aspx for a list of servers. Used in aprs_sender.
• server_port - APRS-IS server port. 14580 is defined in the APRS-IS spec. You probably won't want to change this. Used in aprs_sender.
• api_key - API key for aprs.fi. Requires an aprs.fi account. See https://aprs.fi/page/api. Used in aprs_query and aprs_msg_check.

aprs-sender

Send a message via an APRS-IS server to a destination APRS station.

Usage

Requires destination state and message. These can be either passed as a parameter when running the script or via interactive input.

> python3 aprs_sender.py CALLSIGN test message

> python3 aprs_sender.py
Destination Station: CALLSIGN
Message: test message

Example

> python3 aprs_sender.py
Destination Station: CALLSIGN
Message: test message

Packet to be sent:
 
user CALLSIGN pass XXXXXX vers aprs_tools 1.0
CALLSIGN>APRS,TCPIP::CALLSIGN :test message

Received: # aprsc 2.1.11-g80df3b4

Received: # logresp CALLSIGN verified, server T2VAN

Connection Closed

aprs_query

Query aprs.fi for basic station information.

Usage

Requires target station. This can be either passed as a parameter when running the script or via an interactive input.

> python3 aprs_query.py CALLSIGN

> python3 aprs_sender.py
Station: CALLSIGN

Example

> python3 aprs_query.py
Station: CALLSIGN
class a
name CALLSIGN
type l
time 2022-09-08 06:45:59
lasttime 2022-09-19 06:52:13
lat 44.28683
lng -70.524
symbol R&
srccall CALLSIGN
dstcall APDW16
phg 2040
comment RPi Zero + Direwolf iGate
path TCPIP*,qAC,T2MCI

Description (from aprs.fi docs)

• class - class of station identifier (a: APRS, i: AIS, w: Web ...)
• name - name of station, object, item or vessel
• showname - displayed name of station (may differ from the unique name)
• type - type of target: a for AIS, l for APRS station, i for APRS item, o for APRS object, w for weather station
• time - the time when the target first reported this (current) position (the time of arrival at current * coordinates)
• lasttime - the time when the target last reported this (current) position
• lat - latitude in decimal degrees, north is positive
• lng - longitude in decimal degrees, east is positive
• course - Course over ground / COG, in degrees
• speed - Speed, in kilometers per hour
• altitude - Altitude, in meters
• symbol - APRS symbol table and code
• srccall - Source callsign - either APRS source callsign or AIS vessel callsign
• dstcall - APRS packet destination callsign
• comment - APRS comment or AIS destination and estimated time of arrival
• path - APRS or AIS packet path
• phg - APRS PHG value
• status - Last status message transmitted by station
• status_lasttime - The time when the last status message was received Please respect aprs.fi terms especially with regards to query rates.

aprs_msg_check

Query aprs.fi for the 10 most recent messages sent to a station. This can be either passed as a parameter when running the script or via an interactive input.

Usage

> python3 aprs_msg_check.py CALLSIGN

> python3 aprs_sender.py
Station: CALLSIGN

Example

> python3 aprs_msg_check.py
Station: CALLSIGN
Displaying 2 most recent messages 

{'messageid': '82180175', 'time': '2022-09-19 07:07:50', 'srccall': 'CALLSIGN', 'dst': 'CALLSIGN, 'message': 'test message'}
{'messageid': '82178723', 'time': '2022-09-19 05:48:34', 'srccall': 'CALLSIGN', 'dst': 'CALLSIGN', 'message': 'test message 2'}

Description (from aprs.fi docs)

• messageid - an incrementing id of the message (will wrap to 0 some day)
• time - Time when the message was received
• srccall - Source callsign
• dst - APRS message destination
• message - The message contents Please respect aprs.fi terms especially with regards to query rates.

Credits

• https://www.aprs-is.net/Connecting.aspx for technical spec.
• https://github.com/wa1gov/Simple-Shell-APRS/ for reference implementation in bash.
• https://aprs.fi for cloud APIs and testing tools.