1)   MultiMode 4.6.0
MultiMode allows you to decode and transmit morse code (CW), RTTY, FAX, SSTV, SITOR-B, NAVTEX, PACKET, ACARS, PSK31, ALE, and many other modes on your Macintosh, without any extra hardware.

 2)   SeaTTY 2.0
A program to receive weather reports, navigational warnings and weather charts transmitted on longwave and shortwave bands in RTTY, NAVTEX, HF-FAX (WEFAX), GMDSS DSC and NWR-SAME modes. Only receiver and computer with a sound card are necessary.