Available v0.3.0-alpha

ReticulumHF

Reticulum Gateway for HF Radio

What It Does

Pre-built Raspberry Pi SD card image that runs Reticulum over HF radio using the FreeDV modem. Connect your phone running Sideband or MeshChat to the Pi’s WiFi, and send encrypted LXMF messages without internet.

Flash the image, boot the Pi, connect your radio via Digirig, and complete the 6-step web wizard. No command line required. Supports DATAC1, DATAC3, and DATAC4 modes with instant switching and live RX level monitoring.

What’s New in v0.3.0-alpha

Switch FreeDV modes and adjust TX volume without restarting services. Live RX level display updates every second. Cleaner mobile-friendly interface with ALSA sliders removed.

Previous releases added TX audio control, unified port 4242, the 6-step setup wizard, and audio monitoring.

FreeDV Modes

Select your mode on the status page based on band conditions:

Mode Bitrate Min SNR Use Case
DATAC1 290 bps 5 dB Default - good conditions
DATAC3 124 bps 0 dB Moderate conditions
DATAC4 87 bps -4 dB Poor conditions, weak signals

IMPORTANT: All stations must use the same FreeDV mode to communicate. Coordinate with other operators before changing modes.

Requirements

Raspberry Pi 4 (4GB recommended), 16GB+ microSD card, HF transceiver, digital interface (Digirig Mobile or Digirig Lite), and an Android phone with Sideband.

Tested with Xiegu G90 (Digirig Mobile, CAT + PTT via RTS), Yaesu FT-818 (Digirig Mobile, Hamlib 1020/FT-817), and (tr)uSDX (Digirig Lite, VOX mode).

Quick Start

  1. Download from GitHub Releases
  2. Flash with Raspberry Pi Imager - select “Use custom”
  3. Insert SD card, connect radio via Digirig, power on
  4. Wait 60-90 seconds for first boot
  5. Connect phone to WiFi: ReticulumHF (password: reticulumhf)
  6. Open http://192.168.4.1 in browser
  7. Complete 6-step setup wizard

Setup Wizard

The web-based wizard guides you through configuration:

  1. Select Radio - Choose from supported radios (tested radios marked with [TESTED])
  2. Radio Settings - Shows exact menu values to configure on your radio
  3. Hardware Detection - Auto-detects Digirig, serial port, audio device
  4. Test Connection - Verify CAT and PTT work (or check “Using VOX mode” for audio-only)
  5. Network Security - Optional IFAC encryption for the gateway
  6. Start Gateway - Launches services and redirects to status page

Status Page Features

After setup, the status page shows live RX level from the modem (target -15 to -3 dB for good signal, below -35 dB is quiet). TX volume is adjustable from -20 to 0 dB. Reduce if your radio’s ALC meter is high or power fluctuates.

The FreeDV mode selector switches between DATAC1/DATAC3/DATAC4 instantly without restarting services. Service controls let you restart or view logs for rnsd, rigctld, and freedvtnc2. Connection info shows how to configure Sideband and MeshChat.

Network Configuration

Setting Value
WiFi SSID ReticulumHF
WiFi Password reticulumhf
Gateway IP 192.168.4.1
Web Portal http://192.168.4.1
RNS Gateway Port 4242 (all clients)
SSH pi / reticulumhf

Client Connections

All clients connect using TCP Client Interface on port 4242.

Sideband / Columba: Settings → Connectivity → Add Interface → TCP Client

Setting Value
Interface Type TCP Client Interface
Address 192.168.4.1
Port 4242

MeshChat: Settings → Interfaces → Add → TCP Client Interface

Setting Value
Interface Type TCP Client Interface
Target Host 192.168.4.1
Target Port 4242

Note: If IFAC is configured on the gateway, clients must use matching IFAC Name and Passphrase.

Audio Calibration

The status page shows live RX level directly from the modem:

  1. Tune radio to an active digital frequency (7.078 JS8Call or 14.074 FT8)
  2. Watch the RX Level meter on the status page
  3. Target level: -15 to -3 dB on incoming signals
  4. Adjust radio menu settings if levels are too low or too high
  5. For advanced audio control, use alsamixer via SSH

RX Level Guide:

Level Status
> -3 dB Too hot - reduce radio output level
-15 to -3 dB Good signal level for decoding
-35 to -15 dB Normal (noise floor or weak signal)
< -35 dB Quiet - waiting for signal

Troubleshooting

Radio power fluctuates during TX (4-10W instead of steady 10W): ALC is activating due to TX audio being too hot. Reduce TX Volume on the status page to -8 to -12 dB. For advanced control, use alsamixer via SSH.

WiFi AP not visible: First boot takes 60-90 seconds. Check if the Pi has a solid green LED. If AP doesn’t appear after 2 minutes, power cycle the Pi.

Can’t decode signals: Verify all stations are using the same FreeDV mode. Check RX level on status page (target -15 to -3 dB). Try DATAC4 for weak signal conditions.

Radio not keying (no TX): For CAT radios, check rigctld service status. For VOX radios, verify VOX is enabled in the radio menu. TX volume may be too low to trigger VOX.

Client won’t connect (Sideband/MeshChat): Verify phone is on ReticulumHF WiFi, not mobile data. Use TCP Client Interface with IP 192.168.4.1 and port 4242. Check that IFAC settings match if configured.

Services

Service Purpose
rnsd Reticulum daemon, TCP on 4242 (boundary mode)
freedvtnc2 FreeDV modem, KISS on 8001 (internal)
rigctld Hamlib CAT control with PTT
hostapd WiFi access point

Known Limitations

Alpha release with ongoing testing. Advanced ALSA tuning requires SSH (alsamixer). First boot takes 60-90 seconds. All stations must coordinate on FreeDV mode.

Feedback & Support

GitHub Issues, Discord, or Matrix.

Source Code

Full source and documentation: LFManifesto/ReticulumHF

Reticulum Field Reference for setup guides and config generator. HF Planner to check which bands will work. SEED C2 for sensor networks over Reticulum.

References

Reticulum Manual, Sideband, MeshChat, FreeDV, freedvtnc2.

Open Source

Free software. MIT License.

Download