To quote Bob Bruniga, its creator, 'APRS can be summed up with two concepts, REAL-TIME PACKET TACTICAL COMMUNICATIONS and MAPS. Probably 98 % of APRS potential does not need a GPS or any tracking device. Think of APRS as just a multi-user distributed packet network with a MAP display for many exciting amateur applications.'
It is difficult to define APRS, because of its flexibility of application. Basically, APRS uses AX.25 UI packet frames to communicate position and telemetry. APRS digipeaters rebroadcast the UI frames, usually on the same frequency that they receive on. There is a designed-in technique for forwarding packets by using the UNPROTO path of all APRS TNC's (terminal node controller). APRS commonly uses both HF radio frequencies (at a 300 baud data rate), and VHF radios (typically using a 1200 baud data rate)
APRS can make use of old crystal controlled VHF radio transceivers, TNC's, and 286 PC's or even XT's. You don't need a GPS, but for some applications they are a basic necessity. You don't need a PC on line for some applications, but you do need one for other applications. You don't have to be in a vehicle to use APRS, but it works there fine. It also works if you are walking, biking, skiing, or boating, or even if you are in your basement. Besides presenting an opportunity to use some of the old equipment squirrelled away, there is also a large assortment of state-of-the-art, new equipment which is intended for APRS and similar activities.
Areas of equipment research within APRS include:
Here are a few of the possible aspects and applications for APRS:
The above is by no means an exhaustive list. There are many other aspects and subtlties to APRS, and more to come. What is really nice about APRS is that the getting started cost can be quite low, the getting started technology level can be quite low, and there is early positive feedback in nearly every APRS project.
Please click this icon to forward your comments or suggestions.