Abstract: A real time controller is described for obtaining real time data from a sensor incorporating a memory, comparator, instruction decoder and real time counter. The real time controller solves the problem of gathering real time data as a function of time from a plurality of sensors receiving a plurality of signals.

Abstract: A system to provide warning whenever unreliable data is being received by an airborne receiver for a microwave landing system. The received data is tested against certain criteria to determine validity. The received data is also tested to determine whether it was received via a direct path or via a multipath reflection. A validity counter records the percentage of valid data received. A multipath counter records the length of time data is received via direct path relative to the length of time data is received via multipath. Both counters control warning flags to cause a warning to be generated whenever the counter contents are below threshold values. The validity counter is set to an upper limit when its count crosses the threshold in a positive direction and is set to a negative limit when its count crosses the threshold in a negative direction.

Abstract: A circuit is described for recovering binary data from an input signal which may be phase coded and received intermittently and nonsynchronously incorporating an edge detector for detecting transitions of the data from a 0 to a 1, a counter which may be reset upon detection of a data transition, a second counter which may be reset upon the first counter reaching a predetermined value, the second counter being permitted to free run up to a predetermined value, a circuit for generating data in synchronous with the output of the second counter, and a squelch circuit for inhibiting the output of the generated data in response to output of the counters.

Abstract: First and second redundant command signals are formulated in parallel-by-bit digital format by two ganged wafer switch sets in a control unit. The first redundant command signal is stored in a shift register and subsequently strobed out, by clock pulses received from a remote unit, and transmitted to the remote unit in serial-by-bit format where it is stored and used to control the remote unit. The command signal is subsequently clocked out of the remote unit and returned to the control unit in serial-by-bit format where it is compared against the second redundant command signal to insure that the remote unit has responded to the proper command.A renewable timer is reset by the clock pulses. If the clock pulses are interrupted for more than a predetermined time the renewable timer times out and indicates a fault.