APRS for Beginners: Position Tracking and Messaging Over Ham Radio

Open aprs.fi right now and look at your area. See those icons moving along roads? Those are hams broadcasting their GPS position in real-time over radio. No cell network. No subscription. No monthly fee.

Street prices in this article were checked in July 2026 and move around; verify with a dealer such as HRO, DX Engineering, or GigaParts before you buy.

APRS (Automatic Packet Reporting System) is one of those things that sounds complex until you see it working, and then you wonder why everyone doesn't use it.

What APRS Does

At its core: your radio sends short data bursts containing your GPS coordinates. These get picked up by the network and placed on a live map.

But it does more than that. APRS also handles:

• Two-way text messaging (like SMS but over radio)
• Weather station data broadcasting
• Telemetry from remote sensors
• Object placement on maps (marking event locations, hazards)

All over a single frequency. All without any infrastructure you need to pay for or maintain.

How the Network Moves Your Data

You transmit a packet on 144.390 MHz (North America). What happens next:

1. A digipeater (digital repeater) on high ground hears you and retransmits your packet with more power and better coverage
2. An iGate (internet gateway) hears the digipeated packet and forwards it to APRS-IS — the internet backbone
3. Your position shows up on aprs.fi, aprs.direct, and other mapping sites

In areas with good APRS infrastructure, your packet goes from radio → internet within seconds. In rural areas with no iGates, it might only reach other RF stations within digipeater range. Still useful for local tracking but won't appear online.

Getting On APRS

Option 1: Radio With Built-in APRS

Easiest path. These radios have GPS and APRS baked in:

• Yaesu FT5DR (~$400) — best APRS screen, shows map with stations
• Kenwood TH-D75A (~$600) — excellent TNC implementation
• Anytone AT-D878UVII Plus (~$220) — APRS + DMR combo

Turn on APRS mode, configure your path and beacon rate, done. You're a moving dot on the map.

Option 2: Smartphone + Audio Cable (Budget)

APRSdroid (Android, $4) generates APRS audio tones. Connect your phone to your radio's mic input with the right cable, phone's GPS provides coordinates, radio transmits the packets.

I ran this setup for six months with a Baofeng UV-5R and a $12 Baofeng-to-phone cable from Amazon. Worked fine. Ugly cable management but functionally solid.

The cable varies by radio — search "[your radio model] APRS audio cable" and you'll find the right one.

Option 3: Mobilinkd TNC (~$70-130)

Bluetooth device that sits between your radio and phone wirelessly. Cleaner than audio cables. Pairs with APRSdroid. Acts as a proper TNC (Terminal Node Controller) so packet encoding is more reliable than raw audio coupling.

If you're serious about mobile APRS but don't want to buy a $400 radio: Mobilinkd + any 2m radio + APRSdroid. Solid middle ground.

Settings That Matter

SSID (Station Identifier)

Your callsign gets a suffix number:

• -7 = handheld/walking
• -9 = mobile (car)
• -10 = iGate
• -13 = weather station

So if your callsign is W6ABC and you're in a car: W6ABC-9.

Path

The path setting tells digipeaters how to relay your packet. For 95% of situations:

WIDE1-1,WIDE2-1 — standard mobile path. One fill-in digi hop + one wide digi hop.

Never set WIDE2-2 or higher. It creates network congestion by bouncing your packet through too many digipeaters. On r/amateurradio this is a semi-regular complaint — new APRS users flooding the channel with excessive paths.

Beacon Rate

How often you transmit your position:

• Mobile: SmartBeaconing (adjusts based on speed/turns) or every 90 seconds
• Fixed station: every 20-30 minutes
• Walking: every 2-3 minutes

SmartBeaconing is ideal for driving — it beacons more when you turn or change speed, less when you're on a straight highway. Saves channel capacity while keeping your track accurate.

Cool Things to Do With APRS

Track a road trip. I tracked a 1,200-mile road trip last year — my wife watched my progress on aprs.fi from home without me touching my phone.

Event coordination. Field Day, public service events, charity runs — APRS shows where every operator is positioned.

Text messaging. Send and receive short messages (67 chars) to other APRS users. Works without cell coverage. I've sent messages from national forest roads with zero cell signal.

Weather station. Hook up a Davis Vantage Pro or similar to an APRS TNC and your local weather data broadcasts continuously. Contributes to Citizen Weather Observer Program.

ISS digipeater. The International Space Station has an APRS digipeater. When it passes overhead, you can get your packet digipeated through the ISS. Purely for bragging rights, but what bragging rights.

Common Mistakes

Over-beaconing. APRS is a shared 1200-baud channel. One frequency. Limited bandwidth. If every station in your metro area beacons every 30 seconds, the channel becomes unusable. Be considerate.

Path too long. WIDE2-2 or (god forbid) WIDE3-3 causes your packet to repeat across dozens of digipeaters. The channel gets flooded. Your local APRS community will notice and someone will send you a message about it.

Forgetting it's radio. Everything you beacon is public. Your position, your messages — anyone with a scanner on 144.390 hears it. Don't broadcast from locations you want private.

Not Showing Up on aprs.fi?

Most common issue: no iGate within range. Your packets may be digipeating fine on RF — other local APRS users can see you — but without an iGate to bridge to the internet, aprs.fi won't show you.

Check the iGate map on aprs.fi for your area. If there's nothing within 30-40 miles, your packets aren't reaching the internet.

Other causes: wrong tone on transmit (APRS doesn't use CTCSS — make sure no tone is set), power too low, antenna inadequate, or simply out of digipeater range.

Worth It?

For mobile operators: absolutely. It's useful, interesting, and takes about 15 minutes to set up once you have hardware.

For fixed home stations: maybe. Broadcasting your home coordinates 24/7 is a privacy consideration. Many hams set their fixed station position to their grid square center rather than exact coordinates.

For portable operations (POTA, hiking): excellent. Lets people know where you are without cell coverage.

Total cost to get started: $0-130 depending on whether you already have a 2m radio and go the phone route or buy a TNC.