A supervisory circuit for use in an integrated circuit to supervise the program execution of a processing unit is disclosed. The processing unit generates a restart signal at a particular duty cycle under proper program execution conditions and at an undesirable duty cycle under improper program execution conditions. The supervising circuit includes a capacitive or like circuit element for converting the restart signal into a signal representative of the duty cycle thereof and compares the gener...

A radar having a multiplicity of receive beams stacked in elevation and a target height extractor especially for use therein are disclosed. In operation, a set of range sweeps corresponding to an azimuth scan of the stacked receive beams across a detected target is established. A range cell interval corresponding to the detected target is estimated for each range sweep of the set. A target range measurement is computed from a set of estimated range intervals. Only the radar receive beam echo inf...

Active pilot wire apparatus for replacing a passive continuous metallic wire pair coupling between the electromechanical units of a conventional electromechanical pilot wire protective relay is disclosed. For the protection of a power line section, an electromechanical unit is coupled to each end thereof. Each electromechanical unit includes an operating relay coil which when energized operates breaker contacts to interrupt current through the protected power line section. A signal representativ...

Direct transfer trip apparatus for sharing a common active communication channel utilized for signal transfer between at least two electromechanical units which form a current differential protective relay for protecting at least one power line in a power system network is disclosed. Each electromechanical unit includes an operating relay coil for effecting an interruption of current through the protected power line when an internal fault of the power line is detected. The direct transfer trip f...

A distributed processing unit (DPU) or drop which performs process control and data acquisition functions in a distributed processing control system having a data highway linking a plurality of such units. A DPU functional processor accesses the local process I/O interface thereby continually receiving plant information for storage in digital form and subsequent use in the functional processor or for transmission along the data highway. DPU control programs use process values in a transparent fa...

A decoy radar transmitter governed by a control signal derived from a main radar transmitter to emit radiation which is phase coherent with the carrier frequency of the main radar transmission is disclosed. A section of the main radar transmitter generates a control signal compositely formed by the combination of derived signals including a phase coherent subharmonic of the carrier frequency of the main radar, a frequency shift keyed signal and a signal having a power content. The frequency shif...

An echo-keyed directional comparison blocking system for protecting an electrical power transmission path in a power system network against internal faults is disclosed. The system includes a terminal unit disposed at each end of the transmission path for measuring characteristics representative of the power at its corresponding end and for activating a corresponding circuit breaker when an internal fault of the transmission path is detected. Each terminal unit includes a transmitter and a recei...

A method for making an overlapping electrode structure on an insulation layer comprising selectively etching a conducting layer on the insulation layer to form channels which are oxidized to form conducting ribbons surrounded by an insulating blanket. Contact windows are then opened in selected areas of the insulating blanket such that a conducting material cooperates with the conducting ribbons to form the overlapping electrode structure. In an alternative method, a bilayer structure comprising...

Apparatus for ascertaining the phase coherency of the pulse trains comprising signals in which the phase relationship of pulse trains of one signal sorted from a first dwell of pulses is compared with the phase relationship of the pulse trains of another signal sorted from a second dwell of pulses to determine the phase shift between the signals. At a substantially later time, the process is repeated to again establish the phase shift between the signals, and the two phase shifts are then compar...

A microprocessor-based control system for controlling the speed of a steam turbine by governing the steam supplied thereto from a steam supply source using one or more hydraulically operated servomotor throttle valves is disclosed. The operation of the speed controller is characterized by a plurality of permanently pre-programmed read-only memories containing sets of instructions and data words arranged in an addressable order. The instructions and data words are synchronously processed by the m...