WeFax Decoder

Decode HF weather fax (radiofax) from maritime and aviation weather services. Stations broadcast weather charts on fixed schedules via HF radio.

Station

Settings

Disable this if your source already provides USB dial frequencies.

HF Antenna Guide

HF band (2–30 MHz) — requires HF antenna + direct sampling SDR

Requirements
  • SDR: RTL-SDR (direct sampling), HackRF, LimeSDR, Airspy, or SDRPlay
  • Antenna: Long wire (10m+), random wire, or dipole for target band
  • Mode: USB (Upper Sideband) demodulation
  • Signals: Moderate — HF propagation varies by time of day
Quick Reference
Protocol AM Facsimile (ITU-T T.4)
Carrier 1900 Hz
Deviation ±400 Hz
Black / White 1500 / 2300 Hz
Start / Stop tone 300 / 450 Hz

Auto Capture

Automatically decode at scheduled broadcast times.

Resources

NWS Radiofax Charts NOAA Radiofax Schedule (PDF)