Tutorial MeshCom

Tutorial: MeshCom

What it is. MeshCom is an amateur radio LoRa mesh messaging network on 70 cm (MeshCom 4, see icssw.org). Licensed amateurs use it for short messages and positions. OnAir lists the stations, plots them on a map and shows the chat.

Read this first. Receive only; OnAir does not transmit. Amateur signals are meant to be received, and receiving needs no licence in most countries. Check your local rules. See Legal.

What you need

• A radio that reaches 433 MHz at 1 to 2 Msps. An RTL-SDR is enough. The mode table covers 400 to 2500 MHz.
• A 70 cm antenna.
• Frequency: 433.175 MHz (the start, listed in the database as MeshCom 433 MHz). The mode tooltip says MeshCom 4 uses sync word 0x2B, coding rate 4/6, 433.175 MHz SF11 250 kHz (EU) and the firmware's other country profiles.

Before you start

MeshCom shares the 433 MHz region with LoRa APRS and other LoRa users. Each network has its own settings, so use the matching mode. Moderate gain.

Step by step

1. In the mode list open Amateur: voice & packet and choose LoRa, 433.175 MHz.
2. Pick the radio and start the receiver.
3. Open Settings. Under Networks tick MeshCom.
4. Choose the Band plan (the 70 cm plan) or Custom for your own LoRa setting.
5. Watch Stations, Map, Chat and Packets.

What you should see

Stations with callsigns, positions where sent, short messages in Chat, and the raw frames in Packets.

Reading the screen

• Stations: callsign, position, last heard.
• Map: stations with a position.
• Chat: messages.
• Packets: received frames with SNR and level.
• Settings: networks, band plan, LoRa setting.

Options and settings

Search covers every known MeshCom channel inside the captured band. Custom keeps one LoRa setting of your own.

Troubleshooting

• Nothing heard. Few stations in some regions; check the frequency of your country's profile.
• Frames but no text. The sync word or coding rate does not match.
• Mixed with LoRa APRS. Untick LoRa APRS if you only want MeshCom.

Tips

Stations beacon at intervals; wait several minutes.

Legal and privacy notes

MeshCom is an amateur service. Positions and callsigns identify people; do not republish them out of context.

Under the hood

LoRa physical layer (SF11, 250 kHz, 4/6 in the EU profile) with the MeshCom framing described by the project.

Related

Mode-MeshCom, Tutorial-LoRa-APRS, Tutorial-Meshtastic, Tutorial-LoRa-raw, Live-map, Modes, Main-window, Supported-radios, Troubleshooting, FAQ, Legal, Voice-codecs.