APRS system is short for Automatic Position Reporting System and can be translated as Automatic Position Reporting System.
Basically, amateur radio is notified of the location and what is done at the moment is indicated by icons. Usually the VHF frequency is used, but APRS signals are also broadcast from the HF band. In the APRS System, frequencies in Europe: 144.800, America: 144.390 MHz are used in the VHF band.
Although the primary purpose of the APRS system is to report a location, its use has been extended with details such as mutual message transfer and the addition of automatic meteorology systems to APRS. And even using the internet, it can be communicated with the APRS station (of course, if its data is on the internet) anywhere in the world.
The APRS System was developed by Bob Bruninga, WB4APR. While Bob Bruninga’s son was traveling in the USA for some reason, he sent messages like “I am here now” via packet radio others from certain points, and as Bob received the messages, he marked them on the map and followed roughly a position. Then, by combining this system with GPS, he developed the coordinates not automatically by hand, but by taking them from GPS automatically and sending them to the air in certain periods. The second step was to use special APRS others to carry the signals instead of the packet radio ones. At the last stage, the data received from APRS others are automatically entered into the internet and location tracking is provided independently from the wireless device via the internet.
GPS location, temperature, humidity, altitude, voltage, etc. You can send any data you like. You can even share a very long message / comment. The important thing is not to exceed the total amount of data allowed by the APRS system.
Since VHF frequencies in the 2 meter band are generally used in APRS broadcasts, only Amateur Radios can broadcast at these frequencies. Therefore, only those who have the necessary license can use APRS technology. A person who is not an amateur radio can not use an APRS system.
Why is APRS Necessary?
You can monitor the users of the system visually
If the APRS system used in Mobile can work bidirectionally, that is, it can send and receive messages; Mutual Messaging, You can even e-mail.
On mobile devices, you can see the data of one-way workers such as speed, vehicle temperature, direction, voltage and height above sea level on the map.
You can instantly monitor the movements of those who have APRS in their mobile devices.
With the new feature of APRS on handheld radios, direction determination can be made in emergency situations.
You can see Earthquake data instantly in our country. If you have a program such as UI-View32 or a device such as TM-D700, TM-D710, FTM350, VX-8, TH-D72 with APRS feature, you can see it as a message on device screens without needing internet.
It is called stations that repeat APRS signals from digital format airborne. Digis are usually placed at high points like Repeaters.
It is the system that sends APRS signals received from the air to the internet. If it works as I-GATES + DIGI, it throws the information it gets from the internet into the air again.
Internet Lovers; Systems that transfer all APRS data on the internet to each other.
Local Lovers; They process the APRS information they receive from the air independently from the internet and superimpose them on the map. Or they show incoming messages on the screen. You can also send a message to the desired station without the need for internet.
How the APRS System Works
The station transmits messages or data including location information to the air.
Digipeater, which receives APRS signals from the air, gives signals to the air by repeating them properly and without error.
Having heard these signals, the I-GATE station transmits the RF APRS signals it receives to the APRS servers on the internet.
Internet Servers overlay this information on maps and make it visual.
If there is no internet, all kinds of messaging or tracking of the mobile station can be done with the help of a program such as UI-View32 installed on a locally created PC.
So who is listening to these APRS broadcasts? Do I also need to buy a device to listen to broadcasts?
No, you don’t have to. Some amateur radios around the world listen to these APRS broadcasts / data and transmit them to the APRS-IS system, the internet, with the antenna and various devices / software (iGate or Digipeater) they place on the roofs of their homes or workplaces. As it will be seen from http://status.aprs2.net, this data is stored on the servers set up by the volunteers and published on the internet. (If you do not have a digipeater or iGate near you and you will use APRS, then you will need to install an iGate as described in this article to your home or workplace.)
It is an excerpt.