Abstract: A system is described for assisting the hard of hearing in the use of the telephone, in which an in-line text display is inserted in the telephone line before a standard telephone. The in-line display blocks text related digital communications signals to the standard telephone and decodes the text related digital signals to display on a built in display screen.

Abstract: A unified TDD and telephone incorporate intelligent mode switching to permit users of either device to use the integrated unit with the other features remaining largely invisible by sensing various signals including the removal of the handset or the turning on and off of the TDD device to determine the likely mode of a transmission and the detection of text to determining the likely mode of the receive text. This intelligent mode conversion includes a voice carryover mode in which text and voice may both be transmitted.

Abstract: A telecommunication device for the deaf is designed to operate under an enhanced TDD communication protocol. The TDD is capable of communicating with conventional TDDs operating under normal Baudot/Weitbrecht communications, but is also capable of communicating with a similarly enhanced TDD utilizing an enhanced protocol with a faster data transfer rate. The enhanced TDD is capable of signaling to another remote TDD through the use of a synchronization character that it is capable of enhanced TDD communications. If a similar synchronization character is received from the remote station, both TDDs can then switch to enhanced TDD communication with its advantages of speed and enlarged character set. The synchronization character is especially designed so as not to interfere with the operation of a conventional TDD which might receive the character and also to be sufficiently distinctive so as to be capable of definite reception by enhanced TDD machines with minimum error.

Abstract: A telecommunication device for the deaf is designed to operate under an enhanced TDD communication protocol. The TDD is capable of communicating with conventional TDDs operating under normal Baudot/Weitbrecht communications, but is also capable of communicating with a similarly enhanced TDD utilizing an enhanced protocol with a faster data transfer rate. The enhanced TDD is capable of signaling to another remote TDD through the use of a synchronization character that it is capable of enhanced TDD communications. If a similar synchronization character is received from the remote station, both TDDs can then switch to enhanced TDD communication with its advantages of speed and enlarged character set. The enhanced protocol permits increased functionality of the TTD terminals in providing machine-to-machine communication in a manner invisible to the TTD user. A machine-to-machine control character similar to the synchronizing character is used to designate such messages.

Abstract: A telecommunication device for the deaf operates under conventional Baudot communication protocol, but has enhanced features enabling it to handle interrupts either from a conventional or a similar TDD. The improved TDD is also capable of pseudo-duplex communication with a similar TDD in which each device transmits packets of characters alternatively to the other thus making it appear to the users that simultaneous transmission is occurring. The implementation of these features is done in such a way that the TDD is fully capable of communication with existing TDD devices and the device obeys normals rules and conventions for Baudot communication.

Abstract: A telecommunication device for the deaf includes a self-identification sequence which automatically commences upon the initiation of communication with the device. The self-identification sequence consists of a series of characters which may be separated by pauses and the device listens during the pauses to see if TDD communication has been established. The purpose of the character string is so that a receiving station can identify, with a low rate of error, a calling TDD and therefore switch the incoming call to a TDD equipped operator. This capability is particularly useful for emergency service operators (911 services) which must be able to handle incoming TDD calls with a maximum of efficiency and a minimum of error.

Abstract: A tissue cassette which includes an open-topped, perforated base member adapted to receive a tissue specimen, a perforated lid member adapted to cover the base member and be secured thereto in a closed position, and one or more gates joining the lid members to the base member in an open position wherein the gates will break when flexed.