Expand the MeshCore Infrastructure

with repeaters

What Are Repeaters?

Repeaters form the foundation of the MeshCore network. Companions can communicate via repeaters, allowing them to bridge long distances of up to 64 hops.

Proposed Construction Project

Most repeaters are solar-powered. This makes them self-sufficient and accessible around the clock, as long as the batteries are sufficiently charged. The proposed design described here is intended only to illustrate what is needed to participate in the MeshCore network using simple means.

Components

Only a few components are needed to build your own repeater:

With these components, the total cost comes to approximately €30.

Assembly

1. Prepare the solar panel

To connect the solar panel to the MPPT charge controller, the USB component on the solar panel must be removed. To do this, remove the adhesive-backed plastic housing and desolder the panel’s two solder tabs from the USB board.

2. Connecting the Components

The solar panel is now connected to one of the two solar inputs on the MPPT charge controller. The batteries and the XIAO nRF52840 must also be connected to the MPPT charge controller. The outputs for the batteries and the output to the load—that is, the XIAO nRF52840—are electrically connected to each other. Therefore, it doesn’t matter which connections you make where.

3. Enclosure and Assembly

Drill a hole in the upper third of the housing through which the solar panel’s connection cables are routed. The mount is also fitted with a similar cable grommet. Next, the mount and the housing shell are glued to the solar panel using silicone. This ensures a sufficient seal. Once the silicone has dried, the antenna is attached to the mount and the antenna cable is routed through a grommet at the bottom of the housing. The components are then electrically connected. After flashing the XIAO nRF52840, the housing can be screwed shut.

I used a concrete anchor from the hardware store—which cost just under €4—as the repeater’s mount. This allows the repeater to be attached to a tree, house, or pole.

Settings

These are the additional settings for the "General Settings" mentioned above; we recommend using them for all repeaters.

Admin Password

It is recommended that you change the default password “password” to a secure, personal password to prevent third parties from making changes to the repeater.

Guest Password

The guest password can be left blank. This allows other users to view the repeater’s basic statistics, telemetry data, and neighbors without being able to change any settings.

Advert Interval

With the following two settings, repeaters can automatically advertise themselves.

Zero-Hop Advert

0 – Disable, as this is only a local advertisement that is essentially unnecessary. The Flood Advert setting below also covers Zero-Hop Advert.

Flood Advert

48 – Set this value to 48 hours to avoid unnecessary traffic. Companion nodes do not need to know about repeaters to use them, so it is not really important for repeaters to send many ads.

RX Delay

0.0 – This is currently the best setting recommended by the MeshCore community.

TX Delay

0.5 – This is currently the best setting recommended by the MeshCore community.

Time

It is very important for MeshCore that the repeaters are set to the correct time, as otherwise problems with the adverts may occur. The easiest way is to use “Remote Management” via the Android or iOS app with a Companion Node. For RAK-based repeater nodes, it is recommended to add the RTC module.

Map

It is strongly recommended that repeaters be added to the official MeshCore map. This can be done directly through the MeshCore Android or iOS app.