Understanding Meshtastic Public Channels
The Primary Channel is the main channel every Meshtastic device uses to communicate with others on the same mesh. Every device has one Primary Channel. It carries periodic broadcasts such as node telemetry, status, and optional location information.
For most deployments including NWI Mesh Net, the Primary Channel uses the default public mesh channel (usually named LongFast) so that devices can automatically see and mesh with each other.
What the Primary Channel Is Used For
The Primary Channel handles the following traffic:
- Node presence and identification
- Telemetry such as battery level and signal quality
- Position broadcasts when enabled
- General broadcast messages
The Primary Channel is usually public so that nodes within range form a shared mesh by default. If you need a private mesh for your group, you can configure a private channel and give it a key. That channel will behave like a private group while the Primary Channel remains the main mesh channel.
1. Internet Bridging (MQTT)
Meshtastic can optionally bridge radio traffic to the internet using MQTT. This allows messages and node data to appear on public services such as maps and dashboards.
Uplink Enabled
When Uplink is enabled, your node sends radio traffic it hears to the MQTT server.
This is required if you want your node to appear on public mesh maps.
Downlink Enabled
When Downlink is enabled, your node receives messages from MQTT and rebroadcasts them over the radio.
Caution:
Only turn on Downlink if you have a very stable connection and want to “feed” internet messages into your local mesh. Too much downlink traffic can overwhelm a small local radio network.
2. How to Enable Uplink and Downlink
These are per-channel settings. To enable them for the public mesh:
- Open the Meshtastic app
- Go to Settings
- Select Channels
- Tap the Primary Channel (LongFast)
- Enable Uplink and or Downlink as appropriate
- Save and send the configuration to the device
3. Location Sharing
Location sharing allows your node to appear on mesh maps and helps others understand network coverage and routing. How location is provided depends on how your node is being used.
There are three common scenarios.
Location Source Options
1) Phone-Attached Nodes (No GPS)
This applies when your node does not have built in GPS and is connected to your phone using Bluetooth.
In this case, the phone supplies location data to the node.
Steps:
1. Open the Meshtastic app
2. Enable “Provide phone location to mesh”
3. Keep the phone connected while you want the node to update its position.
Important notes:
Location updates only occur while the phone is connected
If the phone disconnects, the node will stop updating its position
This is best for temporary or portable uset.
2) Fixed Location Nodes (Stationary Installations)
This applies to nodes that stay in one place, such as rooftops, towers, or base stations.
A fixed location allows the node to continue broadcasting its position even when no phone is connected
Steps:
1. Provide an initial location using GPS or phone location
2. Open Radio Configuration
3. Go to Position settings
4. Enable Position
5. Enable Fixed Position
Once enabled, the node will continuously advertise the same coordinates.
Best use cases:
Rooftop or attic nodes
Always-on infrastructure nodes
Solar or PoE powered gateways
If the node is moved, disable Fixed Position, update the location, then re enable Fixed Position.
3) Nodes With Built In GPS
This applies to nodes that include onboard GPS hardware such as T-Beam, T-Deck, or Heltec models with GPS.
These nodes determine their own location and do not require a phone connection.
Recommended behavior:
Use Live Location for mobile nodes
Use Fixed Position for stationary installs once GPS lock is established
Tip:
Allow the node to acquire a solid GPS fix before enabling Fixed Position so the stored coordinates are accurate.
Location Precision and Privacy
The Primary Channel is public, so location settings should balance visibility and privacy.
Recommended settings:
- Precise Location: Disabled
- Position Broadcast Interval:
- Portable or mobile nodes: Default
- Fixed nodes: 1800 seconds (30 minutes)
Disabling precise location slightly offsets the reported position while still showing useful coverage data.