Repeater guide¶

This guide should help you configure a Meshcore "repeater", which makes the mesh grow. You might not need a repeater, look at the coverage map to see if there's coverage in your area.

If there's a nearby repeater and you don't see it with your companion, a repeater on your roof or window could! Give it a try.

See also the question Should I install a relay? in the FAQ.

Hardware¶

Pick a device in our hardware review notes or the Meshtastic hardware list¹.

It's cheap! Expect to pay 50$CAD for a development kit, 150$CAD for a decent solar relay.

Tip

If the device you picked comes with a removable antenna, make sure you connect the antenna before powering up the device. A radio that transmits without an antenna can damage itself!

Software¶

Now you own a LoRa transceiver, congratulations! The next step is to make sure it runs Meshcore by installing firmware on it, and that you can talk to the device, typically by installing an app on your phone.

Flash the firmware on the device¶

First you need to flash your device, which essentially means connecting to the following website.

https://flasher.meshcore.io

Your web browser must support the Web Serial API, which includes Chrome (and derivatives) and Firefox 151 or later.

You may skip this step if it comes flashed with Meshcore already.

Connect your device to your computer using a USB cable. Note that for some USB-C cables, you might need to flip the cable over for the connection to work. A good hint is whether the device is charging or not from your laptop: if it isn't, it means it likely isn't connected correctly.

On many devices, you need to enter some special mode for flashing to work. Here are examples:

Heltec: hold the "program" (PRG) button while connecting the USB cable. For the Heltec v4, it will show up as a JTAG device. On the Heltec v3, it will show up as a CP2102 USB to UART Bridge Controller.
RAK: double-click the reset button will bring it in "DFU" mode, but the web flasher should also be able to do that automatically.

Bug

We have had trouble flashing RAK4631 device. You can:

download the U2F file
put the device in "DFU" mode
mount it
copy the file on the disk
unmount

This can also be done automatically with this reflashtic command:

reflashtic.py --pmount -i RAK_4631_companion_radio_ble-v1.15.0-dee3e26.uf2

The adafruit-nrfutil command can also apparently be used for this.

During first boot, the device will display the message, if it has a display:

Loading...

... for a solid minute, that is normal. If it doesn't have a display, think about how it will stall for a minute.

Flashing an observer¶

If you want to setup an "observer", you should head over to the observer.gessaman.com flasher and flash that firmware instead. It will flash a custom firmware that automatically connects to WiFi and MQTT to relay packet data.

You should not flash an observer if there is already one in your local area. As a rule of thumb, if you're multiple hops from the nearest observer, or it's far enough that it doesn't see your traffic, it's a good idea to set one up. Otherwise, we might not need your observer!

You can setup the observer as a Room Server if you want one of those in your area, but similarly, we might not need one of those if there is already one around.

In any case, it's likely not necessary to setup the observer as a "repeater" unless it's the only repeater in your area. In that case, either set it up as a room server or as a repeater with repeat turned off. This will help reduce the noise on the mesh.

Boot loader OTA fix¶

Advanced users only

This section is a little more advanced and not required for beginners.

You might want to flash upgrades "over the air" (OTA) if your device is in a hard to reach location. There are problems with built-in boot loaders for this, so it is recommended to flash this alternative boot loader.

For that, you need to flash a custom boot loader, before you install the device in the remote location:

find and download the right device file in the last release of the release list, which should end in a .uf2, for example in the current release the SenseCAP Solar P1 file is the update-sensecap_solar_p1_bootloader-0.9.2-OTAFIX2.2-BP1.3_nosd.uf2
connect the device to your computer over USB
put the device in DFU mode, which typically involves double-clicking on the reset button (clicking twice within 500ms)
mount the device that appears
copy the .uf2 file to the device

This should take only a short time and reboot the device.

OTA upgrades¶

Advanced users only

Over-the-air (OTA) upgrades are risky and should be used only if remote access is inconvenient, or if you have a secondary device to run a first test run on.

Beginners shouldn't need to follow those instructions.

You should also not do your initial flash over the air, it's not worth it!

Only use this for upgrades and only if you performed the above Bootloader OTA fix!

Once your device is correctly flashed for OTA (over the air) upgrades, you should be able to perform upgrades remotely, by following this official guide or the Ottawa Mesh guide. A few tips:

if you have a custom Android firmware, you might not have access to the App store and the nRF Device Firmware Update app. You can add this GitHub repository to Obtainium instead, which works fine.
you must change the settings in the app before flashing the upgrade, if you get a timeout, it's because the settings are wrong.
flashing over Bluetooth is slow, we're seeing 3KB/s transfer speeds

Here is a full procedure, but see the official or Ottawa mesh guide if it fails (and let us know):

install the nRF Device Firmware Update app (source code which can be installed through Obtainium)
configure the right settings in the app which is called DFU:
- Packet receipts notification - ON
- Number of packets - 8
- Request high MTU (Android only) - OFF
- Disable resume - ON
- Prepare object delay - 0 ms
- Force scanning - ON
Leave the other settings untouched.
download the right firmware for your device in the Meshcore web flasher interface, make sure you pick the .zip file!
connect to the device command-line, which should be accessible over the LoRa management interface
type the following magic command:
```
start ota
```
This will show the Bluetooth MAC address of your device, which can be used to identify it below.
back in the app, start the update, by tapping Select and picking the .zip file you downloaded earlier
select the device which should show up as something like SENSECAP_SOLAR_OTA and also show the MAC address above
press start

This will go through various steps. If you have messed up the settings, it will like timeout at the DFU initialized step. Otherwise it should show a progress bar and transfer rate after that.
you're done!

Backing up before flashing¶

You might want to backup the router configuration before flashing, but this is less critical than the companion as there's less configurations (e.g. channels, contacts, are not present) than on companions.

Still, keeping a backup of the repeater key is a good idea, you can follow the companion backup procedure.

Configuration¶

A repeater is configured through a web interface. Some settings can be performed over Bluetooth later.

Warning

Some Meshcore configurations exposes your location by default on devices which have a GPS device! To work around this problem, you can disable the GPS or reduce the coordinates precision, we recommend two digits (~1km) for clients and 3 digits (~100m) for repeaters.

You need to at least:

Radio settings: "recommended USA / Canada"
Display name: your name, YUL-Area for a repeater, for example YUL-Villeray, YUL-Parc-Extension, etc
Region: do not set a region, as we currently do not use one, and it will interfere with routing
Admin password: set a strong password and save it to your password manager for remote administration
Path hash mode: pick 3-byte (2), see multi-byte path routing for details
Send an advert! by default, repeaters do automatically send adverts, but it can take hours, during which time your companion won't see the repeater! so do send one manually

Tip

Many settings can be done over a serial port, if you're an advanced user. You can connect to the serial port on Linux with tio:

tio /dev/ttyUSB0

Then the above commands are:

set name YUL-Villeray

You can also connect to your devices with the meschore-cli program. The full command line reference is available in the upstream documentation.

The "recommended USA / Canada" preset is, at the time of writing, the following settings:

Frequency: 910.525 MHz
Bandwidth: 62.5 kHz
Spreading Factor (SF): 7 or SF7
Coding Rate (CR): 5 or CR5

But you shouldn't need to write those down by hands, generally. Just pick the recommended preset. See the frequencies question for details.

Tip

You can also perform this configuration over the command line:

set freq 910.525
set bw 62.5
set sf 7
set cr 5
set name YUL-Area
set path.hash.mode 2

Repeaters can lose track of time¶

Repeaters can lose their time after reboot.

Make sure the repeater has an accurate clock. Companion apps can be configured to automatically sync the clock on login to workaround this issue.

Repeaters without an accurate clock route packets properly, but its adverts will be ignored until its time is accurate.

Enabling the GPS on a device can keep the clock in sync at the cost of a lower battery life.

Observer configuration¶

Assuming you flashed your device with the observer.gessaman.com flasher above, you need to do extra configuration here:

as above, setup the preset:
```
set radio 910.525,62.5,7,5
```
if setup as a repeater and you already have one of those, turn off repeat:
```
set repeat off
```

setup the right MQTT servers:

set mqtt1.preset meshcore-ca-1
set mqtt2.preset meshcore-ca-2
set mqtt.iata YUL

setup WiFi credentials:

set wifi.ssid YourWiFiNetwork
set wifi.pwd YourWiFiPassword

reboot:
```
reboot
```

You made it! Say hi!¶

At this point, your repeater should be properly configured.

Try to connect to the repeater from your companion to "administer" it. If you don't see the repeater, try connecting it to the configuration interface again and send an advert.

Send a message from your companion, which should go through the mesh. Maybe you'll get better (or worse!) reliability and coverage!

After a while, you should see also some neighbors and improve the range and health of the mesh!

Even if you don't see anything yet, wait a while, you might be a trail blazer!

Meshtastic-supported device are often (but not always!) also working under Meshcore. ↩