Patent US 4,428,685

An instrument for indicating variations in an ambient condition, such as temperature, atmospheric pressure or weather wherein such indications are given by means of synthetic speech. Control signals generated by the memory comparator are employed to selectively activate a speech synthesizer generating selected synthetic speech signals which are fed to a digital-to-analog converter and the analog signals generated thereby are transduced to speech sounds in a speaker. In one form, the instrument is supported in a hand held housing containing electronic circuits and a sensor for sensing temperature as well as a battery, controls, on-off switch, display, speaker and synthetic speech signal generator. In another form, the sensor is supported at the end of a tubular housing to be inserted into a body cavity or the mouth for sensing body temperature and generating signals indicative thereof which signals are transmitted to electronic circuit means via flexible cable to a hand held or table top supported unit containing such other elements. Temperature is both displayed and indicated with sounds of speech.