Abstract: An infra-red telemetry system for transmitting information between a rotating shaft of a dynamoelectric machine and an adjacent stationary location includes a plurality of sources of infra-red radiation spaced equi-distanced from one another around the shaft of the dynamoelectric machine and mounted to the shaft of the machine. Information is coded into a pulse train and the pulse train is used to energize the infra-red sources simultaneously. At least one infra-red detector is mounted at a stationary location adjacent the dynamoelectric machine. The infra-red sources are directed to bounce their radiation off a cover plate having a diffuse reflecting surface and mounted on the rotor of the dynamoelectric machine. The bounced radiation is detected by the infra-red detector and decoded to provide the information from the rotor.

Abstract: An interface apparatus, for remotely controlling a plurality of solenoid actuated switching relays having first and second energizing coils, is capable of providing momentary first and second electrical signals respectively in response to an interruption of an input signal to the apparatus and the initiation of the input signal. The interface apparatus includes a first comparator sensing a change in the input signal, a second comparator sensing a change in the output of the first comparator so as to maintain the second comparator output 180 degrees out of phase with the first comparator output, and first and second monostable multivibrators that each have a trigger input connected to the output of a corresponding comparator so as to generate a momentary electrical signal when the trigger input senses a negative excursion in a change of state at the output of the corresponding comparator.