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)   TrueTTY 2.75
A program for amateur radio digital communications via a sound card. Supported modes are RTTY (Baudot code), ASCII (7 or 8 bits),BPSK31,QPSK31,BPSK63,BPSK125,AMTOR (SITOR,NAVTEX), MFSK16, MFSK8, HF- and UHF-PACKET (AX25), DTMF.