Mesh Buddy Shopping List
What to buy to build a Mesh Buddy: a WisBlock GPS tracker, powered and charged over USB-C, that sends your position over the SEQ MeshCore mesh to aprs.fi. Everything comes from Core Electronics in one order. Prices include GST.
The parts
A RAK4631 starter kit on the small RAK19003 base board, the RAK12500 GPS, and the cable that joins the kit's antenna to the radio. It charges and powers from USB-C, takes a LiPo battery, and has a solar socket.
| Part | Core SKU | What it does | Price |
|---|---|---|---|
| WisBlock Meshtastic Starter Kit 9xxMHz (RAK19003 Base Board) | RW-115093 | The RAK4631 radio and processor (nRF52840 + SX1262), the RAK19003 base board (USB-C, battery, solar, 2 module slots), a 2 dBi SMA antenna and a USB-C cable. | $39.30 |
| WisBlock GNSS GPS Location Module u-blox ZOE-M8Q RAK12500 | RW-110016 | The GPS: GPS, GLONASS, BeiDou, QZSS. GPS antenna included. | $32.05 |
| Interface Cable SMA to U.FL (DFRobot) | FIT0219 | Joins the kit's SMA antenna to the RAK4631's tiny U.FL socket. The kit doesn't include one. 150 mm, SMA female. | $5.46 |
| Total, Core Electronics | $76.81 | ||
Core's forum confirmed in January 2026 that this kit comes without the antenna cable ("this product does not come with any pigtails included"). If yours turns out to have one, you've spent $5.46 on a spare.
Putting the GPS in the right slot
The RAK19003 has two module slots, C and D. RAKwireless rates the RAK12500 for slot A or C, and Meshtastic's RAK19003 instructions use slot C. Slot D is the one people report problems with. In the wrong slot the GPS may show up but never get a fix. Each slot is labelled on the board, and the module is held by one small screw.
You'll also need
- A 3.7 V single-cell LiPo battery with a JST PH 2.0 mm plug. That's the battery socket on the RAK19003, and no kit includes a battery. Mesh Buddy charges it over USB-C. Choose the size for how long you ride: 1000-2000 mAh is a sensible start. Use a rechargeable Li-ion or LiPo only; RAK says the battery must never exceed 4.3 V.
- A weatherproof case that lets the GPS see the sky. Mount the LoRa antenna upright.
- A computer with Chrome or Edge to flash it from Kelly's LoRa Mesh > Mesh Buddy tab. The guide walks you through it.
LiPo batteries are sold with their JST plugs wired both ways round. Compare the red and black wires with the + and − marks beside the battery socket. A reversed battery can destroy the board. If they don't match, get a battery that does.
The RAK19003 has no power switch. To turn the tracker off, unplug the battery. If you want a switch, see the upgrade below.
Should you add the motion sensor?
Not yet. The usual WisBlock motion sensor is the RAK1904 (ST LIS3DH accelerometer). IoT Store has it for $13.20; I couldn't find it at Core Electronics.
Mesh Buddy doesn't read a motion sensor today. It tells moving from parked by GPS speed, which already sets the beacon rate (smart beaconing, at least 2 minutes apart while moving) and the telemetry rate (every 10 minutes moving, every 30 parked). A motion sensor would only help once the firmware uses it to turn the GPS off while you're parked, for longer battery life. When that happens, a RAK1904 fits the RAK19003's free slot D with one screw, so nothing is lost by waiting.
Other ways to build it
| Build | Shop | Total | Notes |
|---|---|---|---|
| The parts above | Core | $76.81 | Recommended Smallest board, no power switch. |
| Add a RAK19001 Dual IO base board (RW-110081) | Core | $98.61 | +$21.80 buys an on/off switch and 6 slots (GPS in slot A). The kit's RAK19003 is left over. |
| RW-115098 kit (RAK19007 + OLED) + RAK12500 + cable | Core | $86.81 | Bigger board (GPS in slot A), a screen Mesh Buddy doesn't need, no switch. |
| RAK19003 kit + RAK12500 | IoT Store | $92.40 | IoT Store lists prices without GST; 10 % added here. Its RAK12500 is $49.50 against Core's $32.05. |
| RAK12501 GPS (Quectel L76K) instead of the RAK12500 | Core | $59.06 | Untested $17.75 cheaper, but a different chip nobody has tried with Mesh Buddy yet. |
| WisMesh Tag or SenseCAP T1000-E, ready-made | IoT Store / Core | $91-109 | Can't run Mesh Buddy Meshtastic trackers; they won't send MeshPRS to aprs.fi. |