APRS stands for Automated Packet Reporting System. A packet(AX.25 format) is sent from your radio’s Terminal Node Controller(TNC), or an external TNC, and received by other receivers in the area.
The US 2-meter frequency is 144.390.
Generally the APRS packet contains Location information, weather conditions, or current Voice Frequency.
The packets can be received by an iGate, which may report the packets to various aprs websites. The one I use is https://aprs.fi
An inexpensive radio($25-40) coupled to a smartphone via an inexpensive cable($20). And I believe the APRSdroid software is free or only a few dollars in the google play store.
One radio that I use regularly is the Baofeng BF-F8+
Be sure to pick up the Baofeng Programming cable, it works great with the BF-F8+ or UV-5R. It’s certainly not necessary, but makes programming the radio with CHIRP much easier..
Anybody that poo-poo’s these Either
They work fine and in some cases better than other devices you could buy for quadruple the cost.
The K2 to TRRS cable works great with the Baofeng and APRSdroid.
A few notes:
The TNC is nice because it takes the signal processing away from your phone/tablet device so you can have notifications and stuff running on your phone.
I’m using the Baofeng with the Mobilinkd TNC1 (There is also a new version TNC2)
The TNC-pi plugs in to your radio via a serial cable and is a hat for the raspberry pi.
I’ve had the TNC-pi around since I got my tech license… but I haven’t set it up yet. Arg. One of these days.
Not an inexpensive setup - A nice radio for the vehicle
Looking into getting the Yaesu FT400DR for my vehicle. It seems to do great with beaconing APRS and Displaying received APRS.
The important part, for me, on this radio was the ability to scan Frequencies for voice, while sending and receiving APRS beacons.
To integrate with a phone or computer there are cables that plug into the back of the unit. As a mobile unit, I can’t think of a reason to do this unless you want to send messages instead of the preprogrammed APRS macros.