Abstract: A backlighted, full travel, sealed keyboard. A translucent membrane is disposed between the keys and a printed circuit board and includes a gasket around its perimeter which is sealingly engaged by the housing for the keyboard. Domes for each key are formed integrally with the membrane, so that a liquid tight seal is formed between the keys and the printed circuit board. The keyboard is backlighted with LEDs disposed on the printed circuit board. The domes are configured to allow full travel for each of the keys so that a desired tactile feedback is provided to the user.

Abstract: A memory means is provided which is adapted to be mounted integral with the transducer element used in a transducer system. The memory may store nonlinearity error information or other information concerning errors in the positioning or scan control for the particular transducer, which information may be utilized by the transducer system to compensate for such errors. The memory may also be utilized to store selected information concerning the measured output characteristics of the transducer element which may be utilized by the transducer system to assure that a desired output level is achieved from the transducer element or that the output otherwise is in conformance with that desired. One or more bytes may be provided in the memory which may be utilized to inhibit use of the associated transducer element for particular fields of use or classes of service.