Abstract: Fast response detection of repeatedly transmitted redundant digital codewords is provided by checking the same bit-position in consecutive n bit codewords. The number m of codewords checked is increased until the number of equal bit values reaches a varying threshold j.sub.m dependent upon m, or until m reaches a maximum M. This sequence is repeated for each of the remaining bit-positions of the codeword. Faster response is provided when an early threshold is reached, eliminating the need to continue checking the same bit-position in the remainder of the M codewords.

Abstract: A power generating and distribution system employs primary and emergency back-up standby generators with the primary generator normally powering a conversion supply from which critical supplies are directly connected to a user system and non-critical supplies are selectively connected to the user system through electronic switching devices. The switching means are activated by a monitor control which compares a sample of the primary generator voltage level with a reference level of the generator output powering the conversion supply and generates a control signal to close the electronic switching devices only when the monitor sample exceeds the monitor reference.

Abstract: Detection of repeatedly transmitted redundant digital codewords is provided by checking corresponding bi-positions for consecutive n bit codewords, counting the number of ones and zeros for each bit-position. When there is at least a preselected threshold J.sub.M of equal bit values for each of the n bit-positions of the codewords, in M or less consecutive codewords, the detection process is complete.

Abstract: A method of overflow and diversion re-routing is disclosed for use in an automatic call distributor system of the type in which an incoming call is assigned to an original gate, that is, a group of agents, but in selected circumstances the call is to be re-routed from the original gate. The ACD system is assumed to be connected to telephone network trunks and possibly one or more dedicated trunks. the method of the present invention has the capability of re-routing excess calls to other destinations, including other switches accessible only by the telephone network trunks. The method includes sending a dialed network number on the telephone network trunks, preferably after making sure that there is a trunk suitable for said destination, which is idle. If there is not one available, even for an alternate re-route destination, then the call is entered in a queue for access to the originally assigned gate.

Abstract: A distributed digital data communication network having widely dispursed nodes provides for effective transmission of messages between each node through the use of flood routing. A response message based upon stored data link status obtained when a message is received through the flood routing protocol selects the shortest time delay path for responding to that message. This process eliminates network instability.

Abstract: A circuit for use in aircraft navigation equipment includes operational amplifiers to drive a cockpit indicator such as an electric meter linearly over a first predetermined range, constantly over a second predetermined range, and out of view over a third predetermined range. A first operational amplifier circuit provides a linear drive to the indicator and a second operational amplifier circuit controls the constant drive current to the meter and defines first and second breakpoints which begin the constant in view and constant out of view responses, respectively. The circuit needs only a single input signal for operation.

Abstract: Microwave circuit layout structure is disclosed for a diode mixer frequency converter. Each mixer port is provided by balun circuitry, and the diodes are isolated from, and on the opposite side of the substrate from, the primary circuits of the baluns. Single and double sideband versions are disclosed, including various combinations of dual and single baluns and porting structure.

Abstract: Temperature stability is quickly achieved for a crystal oscillator mounted in a warm-up crystal oven because the heat is applied proportionally to the mass of the oscillator and circuitry during the initial warm-up period of time and then applied proportionally to the area that will allow compensation for thermal loss after the warm-up period. The oscillator crystal is encapsulated within a case along with an oscillator circuit for the oscillator crystal that is thermally mounted to the case. A controlled heater heats the warm-up crystal oven and crystal oscillator. The controlled heater is controlled by a temperature controller that responds to a first thermal sensor that senses the temperature of the case and a second thermal sensor that senses the temperature of the controlled heater.

Abstract: Microwave circuit layout structure is disclosed for a diode mixer bridge. The circuit layout structure is compact and symmetric, and enables short orthogonal equal length leads from a diode ring quad mixer bridge. The configuration also affords equal path lengths through the diodes to provide precise 180.degree. phase differential image frequency cancellation. The structure also affords precise and consistent mounting of the mixer bridge, to further improve performance.

Abstract: Microwave circuit layout structure is disclosed for a diode mixer frequency converter. The circuit layout structure is compact and symmetric, and enables coplanar diode lead connection.

Abstract: An energy absorbing mechanical end stop for a high speed gear train that is used to drive a variable vacuum capacitor utilizes a friction plate that is mounted to a gear member of the high speed gear train as an energy absorbing mechanism. A wedge member is activated when the tuning of the variable vacuum capacitor approaches a limit and falls between the friction plate and the gear member to which the friction plate is attached. The friction between the friction plate and the wedge member brings the gear member to a stop without damaging the high speed gear train or the variable vacuum capacitor that is driven by the high speed gear train.

Abstract: A circuit for multiplexing a plurality of input signals to a single output signal through the use of N and P channel FETs whereby complementary switching circuitry results in a minimization of power usage in either the active or static circuit conditions. This is accomplished by using a feedback technique and area sizing of the FETs to obtain optimum operational results in addition to the minimal power requirements.

Abstract: The typical gating means (four) in a master/slave flip flop are duplicated for each input signal to be multiplexed through the flip flop and a separate control signal is applied to each set of four gating means for determining which of the plurality of input signals is to be passed through the flip flop. While for a single flip flop there is no advantage in reduction of components, when the flip flop is used as one of a plurality of flip flops such as in a register, the reduction of components (used for multiplexing) is very significant.

Abstract: A method for calibrating and correcting circuit errors induced in an aircraft ILS receiving system is disclosed herein. The spectral components of the input signal are processed through bandpass filters and then rectified and integrated in order to produce an output signal representative of the deviation from the desired centerline course. First and second test signals are generated corresponding to first and second known positions. These test signals are sequentially processed in the same manner as the operational input signals in order to develop first and second position errors which represent distortion and circuit induced errors within the processing system. A corrective function is then derived for a range of operational input signals by interpolating from the first and second position errors. All subsequently processed signals are adjusted by applying the corrective function.

Abstract: A retaining device is provided for preventing removal of a fiber optic connector module from a card cage when a mating fiber optic cable connector is attached to the module. A pivoted release lever on the module has a hook automatically engaging a slot in the card cage upon insertion, and is manually operable to a release position only when the mating fiber optic cable connector is disconnected from the module.

Abstract: A battery monitoring system for monitoring the status of a battery provides for including within the battery package a nonvolatile memory for storing digital data symbols representative of the power that has been supplied by the battery. The equipment in which the battery is utilized has associated with it a power monitor system that senses the power delivered by the battery and converts the sense power into digital data symbols which are applied to the nonvolatile memory for accumulation and thereby maintains a permanent record of the power that has been supplied by the battery.

Abstract: In a digital transmission system, a loop-timing technique is provided for a channel bank which demultiplexes a high speed data stream into a plurality of lower rate channels, and which multiplexes a plurality of lower rate channels to a high speed data stream. Loop-timing is provided without elastic buffers by deriving stuff requests from stuff bits in the received high speed data stream, extracting a high speed clock signal from the received data stream, and applying the stuff requests and the high speed clock signal directly to the high speed multiplexer for providing stuff bits in the transmitted high speed data stream and for clocking the transmitted high speed data stream.

Abstract: A mixer-driver circuit in a code correlator of a spread-spectrum communications system simultaneously multiplies an input RF signal with two phase-offset digitally encoded bit streams. A double-balanced mixer is driven with the difference of the digital signals; the mixer is either inverting, noninverting, or off. Matched ECL bistables which reclock the phase-offset bit streams, and a load current steering circuit coupled to the bistables together provide a balanced, differential drive current to the mixer which switches state faster than the bistables alone. In another embodiment, a single bistable receiving an encoded bit stream differentially drives the mixer in a biphase circuit.

Abstract: A simplified digital NRZ data phase detector is provided with a minimum number of components and with an expanded measuring interval to enable the use of slower speed components. In a phase locked loop application, a first input gate, such as a flip-flop, responds to NRZ data, and a second input gate responds to clock pulses and the output of the first gate. Variable and fixed width correction signals are derived directly from the outputs of the first and second gates, respectively, within a measuring interval initiated by a data transition and terminated by a clock transition. The difference in duration between the directly derived variable and fixed pulses provides phase indication.

Abstract: A proportional digital control system for radio frequency synthesizers using binary coded decimal control to a frequency synthesizer tunable in contiguous small interval increasing or decreasing steps throughout the frequency bandwidth range of operation. A fine tune dial switch circuit generates a two signal output with one a step count signal and the other an up-down control signal generated only upon rotation of the fine tuning dial and with the signal pulse rates thereof a direct function of the rate of fine tune dial turning. The up-down control signal is an up or down signal input to up-down pulse counting to BCD output circuits as determined by phase relation thereof to the step count signal and with the phase determined by direction of fine tune dial turning clockwise for up count and counterclockwise for down count.