MERLIN / ALIS
This is the 240 bd 8 tone burst ARQ mode used in the RS-ARQ Rohde & Schwarz MERLIN modem. When the system is found in the 7 tone mode it is in ISS mode, the IRS mode uses an 8 tone signal. Both will be measured as 240 bd (720 bits/sec) with tones shifted by 240Hz. Character set can be ITA2 or ASCII with 8 bit ASCII being the most common.
Turkish, German and Italian Diplo stations are the most commonly found users. The Italian Diplo stations seem to favor the 5 bit (ITA2) mode. Turkish Diplo stations have been found using the 8 bit mode for all traffic.
Click here for a typical MERLIN sound
Source of info:FAQ in WUN by M.Chase/S.Stalsky