the secure telephones protect voice communications over pstn, epabx, vsat (dama & pama links including double hop), tropo, hotlines, leased lines and ascon networks. three proprietary compression algorithms transform your voice into a digital stream corresponding to the achievable data rates (2400, 4800, 9600 bps). the digital encryption of this data stream features the top-level secure telephones are easy to install, offer many intelligent attractive telephone functions support plain as well as encrypted communications. redialing, a note register and programmable alarm clock functions remind you of your appointments. the menu guided user interface is available in four languages.despite this relatively low data rate excellent voice quality and speaker recognition are reached. voice-controlled half-duplex operation allows protected communications on channels, which do not support the full-duplex mode. features and specifications: the best possible voice quality is selected automatically at data rates of 9,600, 4,800 or 2,400 bps. communicates over satellite channels including inmarsat and gan. all secret elements are securely kept in the removable handy personal security module. hands-free operation. programmable destination keys for immediate dialing. optional encryption of pc or facsimile data, on good lines even simultaneously with voice. can be used like a common telephone. provides intelligent telephone functions. incase of a fall-back to plain both conversation partners are warned by optical and acoustic signals the built-in test equipment (bite) help tracking faults in malfunctioning units. the optional data interface allows encrypted data transmission, on good channels even simultaneously with the conversation