Originally Posted by SVAuspicious
Wefax is transmitted as FSK. Most mariners receive it using SSB (usually USB) which is why the seminal reference rfax.pdf reminds you to offset the tuning frequency by 1900 Hz. If you use LSB you'll need software that can invert the tones.
Oops sorry, dame bramage ... indeed most WeFax is broadcast on Upper Side Band (FSK).
Here's the 'mother of all WeFax' websites on the net, including discussions on smart phones, tablets, etc. etc. History
Using a simple audio patch cord between the radio (simple portable 'Short Wave' with AM/USB/LSB/CW or HF/SSB) and a PC and using simple/fairly inexpensive programs will get you WeFax out at sea. I use a simple audio patch from my SSB (or portable SW receiver) into a Mac using "multi-mode" as the software for WeFax and marine TTY - MultiMode - CW RTTY SSTV FAX MORSE PSK31 ACARS SITOR AMTOR ALE DTMF FFT ASCII Decoding Software for the Macintosh