APRS Information and Links
Amateur Packet Reporting System (APRS)
APRS is a connectionless packet data mode that uses AX.25 protocol (Packet TNC's transmitting UI frames) to transmit position information, foxhunt hound location and beam heading (triangulation), weather station information, telemetry, simple bulletins and messaging. It can for instance be used for tracking moving objects (race followup crew), transmitting ballon telemetry (EOSS), Skywarn Network data exchange (both present weather conditions and observer warnings) and any other use you might want to devise.
The national 2 meter frequency is 144.39, several HF frequencies are also used.
Its networking is fairly simple, no special nodes are needed. All retransmission on an APRS network is done by the use of digipeating with VIAs. TNC's such as the Kantronics KPC-3 Plus and KPC-9612 Plus having special UIDIGI functions specifically designed for this mode.
A basic tracker for this system consists of a GPS receiver capable of NMEA output, TNC and radio. Some radios such as the Kenwood TH-D7A with internal TNC were designed specifically with APRS in mind.
Interfacing to Peet Brothers and Davis Instruments weather stations is possible.
On the receiving end, various software packages with map and data display are available:
The DOS version of APRS provides rudimentary maps; however, it will run on most of the older 386 laptops which makes for cheaper display.
The Windows and Macintosh versions have better graphics and therefore more sophisticated maps.
The APRS+SA version collects APRS traffic and displays it in several modes. In addition it uses the Windows API's to send the position information to DeLorme Street Atlas USA so you can have quite sophisticated maps to view.
One of the most interesting things being done with APRS at this time is the Internet Gateway. Using this method, you theoretically could have digipeaters and strategic home stations with full time internet access to the gateway set up along for instance the I-5 corridor. These stations then take APRS information received by radio and transmit it to the Gateway Server. Your family at home in Medford could connect with a given APRS program to the Gateway Server and track your progress via the internet up I-5 to Portland. Acheiving this will take some dedication and coordination.
APRS - The APRS Webring Site List
APRS - WB4APR Website, Bob Bruninga started it all!
APRS - KCAPRS Website - using APRS for Skywarn, KPC-3 TNC setups
APRS - APRS in the Pacific Northwest - Links Page
APRS - Tucson Amateur Packet Radio Association
APRS+SA - Windows 9x, NT APRS software, for use with DeLorme Street Atlas USA Versions 4-7
APRS+SA - VE5DGD APRS+SA Web Documentation, good information on setup and use
GPS - Garmin International Website - Information and Specs on the Garmin GPS line
GPS - Joe Mehaffey and Jack Yeazel's GPS Information Site
MacAPRS - WinAPRS - X-APRS - APRS for Windows, Macintosh and X-Windows
RADIO - Kenwood TH-D7A setup and useage for APRS and Packet Radio. Windows Control program for the TH-D7A
TNC - Kantronics KPC-3 Second serial port activation for APRS