Thumb Mesh Repeater Operator's Guide

Purpose

This document describes the recommended configuration for repeaters participating in the Thumb Mesh network.

Thumb Mesh is a cooperative effort. We do not control how anyone configures their LoRa hardware, and operators are free to run any settings they choose. These recommendations have proven to work well on the Thumb Mesh network and help repeaters cooperate efficiently.

This guide assumes you already know how to configure a MeshCore repeater. It only covers settings that differ from MeshCore defaults or where Thumb Mesh has a recommended practice.

Recommended Settings

Enable 2-byte Path Hashes

set path.hash.mode 1

Thumb Mesh recommends enabling 2-byte path hashes on all repeaters.

Older MeshCore firmware defaulted to 1-byte hashes (path.hash.mode 0). While those repeaters continue to forward traffic correctly, modern MeshCore flood routing and companion applications expect 2-byte hashes. Repeaters left at the old default may not appear correctly in mapping and discovery tools.

Verify with:

get path.hash.mode

Advertisement Intervals

set advert.interval 240
set flood.advert.interval 24

Thumb Mesh recommends reducing advertisement frequency from the defaults.

advert.interval 240 sends a local advertisement approximately every four hours.
flood.advert.interval 24 sends a network-wide advertisement approximately once per day.

These intervals reduce unnecessary background traffic while still allowing repeaters to remain discoverable.

AGC Reset

set agc.reset.interval 500

The SX1262 radio can occasionally become "deaf" after prolonged exposure to strong nearby RF signals. When this occurs, the receiver's automatic gain control (AGC) can clamp the apparent noise floor, making weak signals difficult or impossible to receive until the radio is reset.

Resetting the AGC approximately every eight minutes helps prevent this condition and is recommended on all Thumb Mesh repeaters, particularly those installed near commercial RF sites.

Guest Password

set guest.password

Thumb Mesh recommends leaving the guest password blank.

This allows other network participants to query repeater status for troubleshooting and maintenance without granting configuration access.

Choosing a Delay Profile

Delay settings determine how long a repeater waits before retransmitting flood traffic.

The goal is to allow the most appropriate repeater to forward first, reducing duplicate retransmissions while maintaining good coverage.

Choose the profile that most closely matches your installation.

Installation	`txdelay`	`direct.txdelay`	`rxdelay`
Infrastructure (water towers, commercial towers, 20+ neighbors)	2	2	3
Elevated (grain elevators, silos, tall barns, 10–20 neighbors)	1.5	1	3
Suburban rooftop (5–10 neighbors)	0.8	0.4	3
Local / low elevation (1–3 neighbors)	0.3	0.1	3
Mobile	3	2.5	3

What the settings mean

`txdelay`

Controls how long a repeater waits before retransmitting flood packets.

Higher values cause taller or better-connected repeaters to defer transmission longer, allowing nearby repeaters to satisfy the flood first and reducing duplicate traffic.

`direct.txdelay`

Applies the same concept to routed (point-to-point) traffic.

It is generally lower than txdelay so direct messages are delivered more quickly.

`rxdelay`

Applies only to flood traffic.

MeshCore delays processing weaker copies of a flood packet while immediately accepting stronger copies. This naturally favors cleaner RF paths without requiring manually configured routing.

Thumb Mesh recommends an rxdelay of 3 for all repeater installations.

Recommended Configuration

Most Thumb Mesh repeaters should have these settings regardless of location:

set path.hash.mode 1
set advert.interval 240
set flood.advert.interval 24
set agc.reset.interval 500
set guest.password

Then apply the delay profile that best matches your installation.