Portable dual-frequency GNSS RTK receiver with a Bluetooth link to a mobile
app. This BOM is derived from the KiCad schematic
(kicad/rover.kicad_sch) and is the authoritative
parts list for the custom rover PCB. A machine-readable copy is in
bom.csv.
The schematic uses an ESP32-C3 (Wemos C3 mini) MCU plus an HC-05 classic Bluetooth SPP module over UART. (The rover firmware README also documents a BLE-only variant on a Wemos D1 Mini32; the schematic below is the built reference design.)
| Ref | Qty | Part | Description | Notes | Est. USD |
|---|---|---|---|---|---|
| U2 | 1 | Wemos C3 mini (ESP32-C3) | Main MCU — UART↔BLE/SPP bridge, OTA | RF_Module:WEMOS_C3_mini footprint |
4–6 |
| J1 | 1 | Quectel LC29H (DA) socket | Dual-band, dual-antenna RTK GNSS module | Mounted on LC29H socket |
35–55 |
| J2 | 1 | HC-05 socket | Classic Bluetooth SPP module (UART) | HC05 socket |
4–7 |
| J3 | 1 | BMS FM5324 socket | Li-ion battery management / power module | BMS_FM5324 socket |
3–6 |
| J4 | 1 | Battery connector (1x02, 2.54 mm) | Li-ion cell input | PinHeader 1x02 horizontal | <1 |
| J5 | 1 | Control-panel socket | Buttons / status LED breakout | RTK_ControlPanel socket |
1–2 |
| Ref | Qty | Value | Package | Notes |
|---|---|---|---|---|
| C1, C2, C5 | 3 | 100 nF | Disc THT (D3.0 mm, P2.5 mm) | MCU/module decoupling |
| C7 | 1 | 10 µF | Radial electrolytic (D4.0 mm, P2.0 mm) | Bulk decoupling |
| C6 | 1 | 100 µF | Radial electrolytic (D5.0 mm, P2.5 mm) | Bulk / power rail |
| R1, R2 | 2 | 300 Ω | Axial THT (DIN0204) | LED / current-limit |
| Qty | Part | Description | Est. USD |
|---|---|---|---|
| 1 | Li-ion battery (e.g. 18650, ~3000 mAh, 3.7 V) | ~20–30 h runtime per firmware estimate | 5–9 |
| 1 | GNSS antenna (L1/L2/L5 multi-band, e.g. helical/patch) | Required for LC29H DA RTK | 20–40 |
| 1 | Antenna cable / SMA pigtail | Match module connector (U.FL→SMA) | 2–4 |
| 1 | Enclosure | See imgs/enclosure*.png in repo root |
5–15 |
| 1 | USB-C cable | Programming / charging | 2–4 |
| — | PCB fabrication | See gerber/ |
2–10 |
Indicative total (excl. enclosure/antenna): ~$60–100 depending on the GNSS module and supplier.
LC29H DA UART1_TX → ESP32 GPIO25 (RX)
LC29H DA UART1_RX ← ESP32 GPIO27 (TX)
VCC 3.3–5V (via power module), common GND
Baud 115200, 8N1, no flow control