APRS (Automated Position Reporting System) is a special version of packet radio. It was developed in 1992 by Bobo, Bruning WB4APR and soon became one of the most vital segments of radio amateurs. Even an enormously large network, such as a pan-European one, is sufficient with one frequency (144.800MHz), on which non-protocol packet data is transmitted - without establishing a connection. The signal can be spread by several digipeaters in a defined area, which are referred to as IGates (Internet gateways) and thus enable connection with suitable Internet platforms such as e.g. aprs.fi or db0anf.de.
The protocol allows information and data of any kind to be forwarded. Any measurable unit can be used as a popular method of determining the position of mobile/portable stations - creates a cheap GPS receiver. Tracking the position of balloons or space objects (the ISS also has APRS on board), connections with other stations are only the basis of the possibilities of this amateur radio operation. APRS is more than an ordinary mode that can be operated by radio (on 144.800MHz) or the Internet.
Unlike other countries, APRS activity is not high in Slovakia yet. On October 20th, I started the trial APRS internet gateway OM9AWJ-10 in Bratislava in Novi mesto. Gateway sa skladá z APRS4R systému na báze routera ASUS500 vyvinutého DO5MC – momentálne najefektívnejšieho a najmodernejšieho riešenia.
QTH IGate is the "Colosseo" and covers the entire city of Bratislava with its signal. Even with minimal equipment, it can be reached from any place in Bratislava. As it is located indoors, it is difficult to get good coverage within a 15km radius, although a few more distant digipeaters such as HG1PNY-1 and OE3XKR (both about 70km away) were picked up. Sometimes it is possible to catch the OM3KTR-2 signal from Trnava and this signal was linked to the Internet. Peter OM3PV told me that a suitable antenna would be needed for a stable connection.
Although the audible activity on 144.800MHz in Bratislava is minimal, I believe that it will increase with the establishment of the OM9AWJ-10 digipeater.
If it is possible, I would like to place the APRS digipeater on 144.800MHz in a more suitable place than my apartment. If anyone can provide a suitable QTH and brand, I am donating a Kenwood transceiver along with the latest TNC OT2m and power supply to set up.
A hearty 73
Christian OE1CWJ/OM9AWJ