Pro MeshCore Solar Repeater: Complete Build

Pro MeshCore Solar Repeater: Complete Build

This guide covers a fully self-contained, weatherproof, solar-powered MeshCore repeater intended for rooftops, hilltops, and any site without mains power. Budget roughly $217 in parts and two to three hours of build time.

Bill of Materials

Enclosure Preparation

Begin with the Hammond 1591XXFLBK polycarbonate box. Drill two cable-gland holes on the bottom face: one 16 mm hole for the LMR-195 antenna pigtail and one 12 mm hole for the solar/battery DC wiring. Install PG-7 cable glands in both holes and tighten the locknuts. Place a 10 g silica gel desiccant packet inside the enclosure before sealing to prevent condensation. Mount the RAK19007 base board to the enclosure floor using four M3 x 6 mm nylon standoffs—never mount directly to the enclosure plastic, as flexing can crack solder joints.

PCB Mounting and Anti-Static Precautions

Before handling the RAK4631, ground yourself via a wrist strap or by touching the enclosure mounting hardware. Seat the RAK4631 into the RAK19007. Route the LMR-195 pigtail through the cable gland (SMA end inside, N-type outside) and hand-tighten before final enclosure assembly. Leave 5 cm of slack inside the enclosure to prevent cable strain on the IPEX connector.

Solar Wiring

Wire the solar panel positive and negative leads to the PV input terminals of the Victron MPPT 75/10. Connect the 10 Ah LiFePO4 battery to the BATTERY terminals, respecting polarity. Wire the LOAD output of the MPPT to the RAK19007 USB-C input via a suitable DC-DC 12 V to 5 V step-down converter (e.g., a mini buck module set to 5.1 V). Use 22 AWG wire for the load circuit and 18 AWG for the battery and panel connections. Secure all wires with zip ties to the enclosure interior.

Antenna Installation

Mount the 8 dBi Taoglas antenna to a standard 1-inch pipe mast using the supplied bracket, positioned at least 1 m above the roofline for minimum ground-plane interference. Connect the N-type end of the LMR-195 pigtail to the antenna base. Apply self-amalgamating tape over the N-type connector and at least 50 mm up the cable for weatherproofing.

Firmware and Configuration

Flash the RAK4631 with the MeshCore REPEATER firmware as described in the Budget Build page. After first boot, configure a fixed GPS position if known (improves network topology display). Enable the low-power sleep mode appropriate for solar-only nodes to extend overnight battery life. Set TX power to 22 dBm. Label the node with its site name and elevation for operator reference.

Pre-Deployment Testing

Before mounting on-site, bench-test the complete assembly: cover the solar panel, run overnight to confirm the battery sustains operation for at least 12 hours, then expose to sunlight and verify MPPT charging resumes. Confirm the node is visible in the MeshCore companion app from at least 500 m away in open terrain before final installation.