Build a MeshCore repeater

Repeater firmware runs on the same boards as companion firmware. A radio running repeater firmware does not accept Bluetooth connections from the app, so you configure it over USB or manage it over the mesh.

Each repeater has its own identity key. Plan firmware updates before you mount it. On some nRF52 boards, including the Wio Tracker L1 Pro, the factory bootloader can't do Bluetooth updates, and the official flasher warns you to install the OTAFIX bootloader first. The flasher also recommends OTAFIX for other nRF52 boards such as the Heltec T114, T096 and T-Echo. Install it before the repeater goes up on a roof.

Open flasher.meshcore.io in Chrome or Edge on a desktop computer. Choose your device, pick the Repeater role, connect the board by USB and flash it. When flashing finishes, the flasher offers a Repeater Setup button that opens the USB configuration tool.

The easiest path is config.meshcore.io. Connect the repeater by USB and use the web page to set the name, frequency and radio settings, location, and passwords. The flasher's Console feature gives you a command line over USB as well.

After setup, you can manage the repeater over LoRa from the MeshCore app's Remote Management feature. Log in with the admin password to reach the command line and settings.

Set the radio first. The frequency must match your region before the app can manage the repeater over the air. For the US preset, the radio command below sets all four values at once. Radio changes take effect after a reboot.

Keep names short: the CLI reference limits them to 23 bytes when a location is set and 31 bytes without one. The FAQ also suggests choosing a repeater key whose first byte doesn't match other repeaters near you, so paths stay clear.

Every repeater and room server ships with the admin password set to the word password. Anyone who knows that default can change your settings, so change it before you deploy. The admin password command echoes the new password back to confirm it.

The guest password works differently by role. On a repeater it gives limited access, for example to telemetry and owner info, and it is blank by default. On a room server it is the password people use to join, and the MeshCore FAQ lists its default as hello, so change it.

The set tx command controls only the power of the LoRa chip. Some boards add an amplifier stage that raises the total output, so check your board's manual. The MeshCore docs warn that a value set too high may break the law in your country, and the FAQ warns that wrong settings on some high-power boards can damage the hardware. Community groups such as PugetMesh and RDUMesh say they keep repeaters at or under 1 watt. Some boards in the FAQ's own table go well above 1 watt, so don't read 1 watt as the legal limit. In the U.S., the rules for this band are in FCC Part 15 (47 CFR Part 15).

Height matters most. The MeshCore FAQ says to place a repeater high above ground, and the official site describes repeaters in high locations. Austin Mesh sums up its advice as height first, then antenna, then power.

Seeed Studio's guide on the MeshCore blog adds practical tips: pick an open spot, mount the node higher, keep a clear line of sight to other nodes, keep the antenna vertical, and keep it away from metal surfaces. PugetMesh suggests a roof or a mast above the roofline for repeaters with omnidirectional antennas.

The official site promotes solar-powered repeaters in high places and lists the SenseCAP Solar Node P1 Pro as a repeater node. Seeed Studio reports about 9 km with the stock antenna on that node in an open test with clear line of sight.

Community builds are simple. PugetMesh lists a roughly $50 parts kit (prices as of September 2025): a XIAO nRF52840 with a Wio-SX1262 radio, an antenna, a small solar panel, a charge board, an IP65 enclosure and a 10,000 mAh battery. RDUMesh describes its nodes as a small waterproof box with a battery, a light antenna and one or two small solar panels, usually under two pounds.

Firmware before 1.18.0 included a low-voltage boot lockout on some nRF52 boards. The 1.18.0 release notes say it is now disabled on most nRF52 boards, so check the release notes for your board. Repeaters also have a power saving option that sleeps between transmissions.

A repeater sends flood adverts on a timer, set in hours between 3 and 168. The MeshCore FAQ says the default is 12 hours and the CLI reference says 47, so run get flood.advert.interval to see yours. Repeaters also stop forwarding other nodes' adverts after 8 hops by default.

To add the repeater to the MeshCore map, open Contacts in the app, tap the three-dot menu next to the repeater, tap Share, then Upload to Internet Map.

To update firmware over the air, log in as admin from the app and run start ota. On ESP32 boards this starts a Wi-Fi hotspot named MeshCore OTA where you upload the non-merged firmware file. On nRF52 boards you use Nordic's nRF Device Firmware Update app with the ZIP firmware file.

Several US groups publish extra settings for repeaters. These are community advice, and the values differ between groups. For example, NashMesh recommends a 2-byte path hash and PugetMesh uses 3-byte. The MeshCore FAQ notes that repeaters on firmware older than 1.14 drop 2-byte and 3-byte packets, so follow your local group's lead. All of the commands below are documented in the official CLI reference.