This is a one-stop Web site for technical characteristics called for in FCC rules § 97.309(a)(4), which reads:

(4) An amateur station transmitting a RTTY or data emission using a digital code specified in this paragraph may use any technique whose technical characteristics have been documented publicly, such as CLOVER, G-TOR, or PacTOR, for the purpose of facilitating communications.

Documentation should be adequate to (a) recognize the technique or protocol when observed on the air, (b) determine call signs of stations in communication and read the content of the transmissions. Click on names of the techniques already documented:

• CHIP64
• CLOVER
• CLOVER-2000
• D-Star
• Domino
• FDMDV
• G-TOR
• JT65
• MFSK
• MT-63
• Olivia (Draft specification provided by the creator of Olivia, Pawel Jalocha, SP9VRC)
• PACTOR
• PACTOR-II
• PACTOR-III
• PSK31
• Q15X25
• RWOP
• WINMOR
• WSPR (MEPT_JT)