WEFAX

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Meteosat WEFAX - WEFAX

WEFAX
Weather Fascimile.jpg
Frequencies 3 MHz,30 MHz
Frequency Range 3 MHz - 30 MHz
Mode USB
Modulation FM
ACF
Bandwidth 3 kHz
Location Worldwide
Short Description Radiofax (Also known as Weatherfax, HF-FAX, WEFAX, and Weather Facsimile) is a slow scan analog image transmission mode used for the transmission of press images, weather charts, newspapers, and meteorological reports.
I/Q Raw Recording
Audio Sample

WEFAX (Also known as Weatherfax, HFHigh Frequency (3-30 MHz)-FAX, Radiofax, and Weather Facsimile) is a slow scan analog image transmission mode used for the transmission of press images, weather charts, newspapers, and meteorological reports. Kyodo News, a Japanese newspaper, transmits entire pages via WEFAX.

WEFAX was originally developed for satellite usage, but has gained usage in the HFHigh Frequency (3-30 MHz) bands in the past decades. Satellite WEFAX use can be seen at Meteosat WEFAX.


Click Here to Hear WEFAX Live at WebSDR Univ. of Twente[edit]

Format[edit]

WEFAX's format is a derivative of the Automatic Picture Transmission (APT) originally developed for transmission from the polar satellites of the USA.

WEFAX has 60, 90, 100, 120, 180 and 240 LPM (Lines per minute) speeds, and two IOC (Index of Cooperation) modes, IOC 576 and IOC 288. Most weather forecasts are sent in IOC 576.

WEFAX frame format
Signal Duration IOC576 IOC288 Remarks
Start tone 5s 300 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). 675 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). 200 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). for colour fax modes.
Phasing signal 30s Black line interrupted by a white pulse.
Image Variable 1200 lines 600 lines At 120 lpm.
Stop tone 5s 450 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz). 450 HzHertz (Hz), unit of frequency, defined as one cycle per second (1 Hz).
Black 10s

Samples[edit]

Speed Modes
120 LPM 240 LPM
120.jpg
240.jpg

Northwood[edit]

Intro Fax End of Trans.
WfaxIntro.jpg
Weather Fascimile.jpg
WFaxEoTNORTHWOOD.jpg

Frequencies[edit]

Typically around 3 MHzMegaHertz (MHz) 10^6 Hz to 16 MHzMegaHertz (MHz) 10^6 Hz. See here for Northwood UK Weatherfax frequencies.

Decoding Software[edit]

Hobby Level Software


Professional Equipment/Software

Video Examples[edit]

Additional Links[edit]

Additional Images[edit]