Abstract: A radio frequency (RF) signal generator is disclosed which generates a baseband signal at a fixed center frequency and having required modulation characteristics. The baseband signal is translated to a desired output frequency signal by mixing with a step-variable local oscillator signal. Fast frequency modulation is achieved by using a fast tuning oscillator as the source of the baseband signal. The output frequency is generated while preserving all modulation characteristics of the baseband signal and to thereby provide high performance modulation having characteristics at a fixed frequency.

Abstract: A function generator having the capability of providing a repetitive output signal with a high degree of versatility in waveform, frequency and amplitude, and with a high degree of resolution. Low frequency (76) and high frequency (86) signal are provided separately, or are combined (108) to provide an amplitude modulated output signal in either a full or suppressed carrier mode (110). Low frequency waveforms are stored (20) and high frequency and user defined waveforms are downloaded from a central processing unit (2). An output attenuator (72, 78, 82, 88) controls the output signal amplitude with a high degree of resolution. An output selective built-in test capability (116) is provided.

Abstract: Analog input/output apparatus includes a plurality of digital to analog converters (18, 20, 22, 24, 26) and a plurality of interfacing means (4, 6, 8, 10, 12, 14, 16) for interfacing the converters with a central processing unit (2). A plurality of current and voltage sources (28, 30, 32, 34, 36, 38, 40, 42) are connected to the converters for providing a plurality of voltage and current stimuli signals and monitor signals. A signal measurement channel (44, 46, 48, 52) is responsive to the monitor signals and is controlled by the interfacing means (4-16), and multiplexers (44, 46) are wrapped around the measurement channel to provide a self-calibration channel (50). The central processing unit is responsive to the self-calibration channel output for determining the correction to be applied to the stimuli signals.

Abstract: Film (13) in a film cassette (15) is connected to a take-up reel (19) in a film transport mechanism (11) by means of mating connectors (20,30) attached to leaders (27,29) on the cassette film (13) and on the take-up reel (19). The connectors (20,30) are retained in contoured slots (41,51) on the cassette (15) and on the film transport mechanism (19) so that when the cassette (15) is loaded onto the transport mechanism (19), the connectors (20,30) will be in alignment. By arranging the connectors (20,30) for connection and disconnection in a direction perpendicular to the direction of travel of the film (13), an efficient connection can be effected and the connection remains stable during the operation of the film transport mechanism (11).

Abstract: A closed loop drive system for a permanent magnet motor (12) operable in a two-phase drive mode during a start cycle and a single phase drive mode thereafter during which the start cycle is reinitiated if the back EMF generated in a sensing winding (18) falls below a reference value. The permanent magnet motor (12) is driven as a two-phase motor with an increasing frequency input during the starting cycle and after initial starting is driven as a single phase motor as long as the back EMF induced in a stator sensing winding (18) remains above a predetermined value. A restart decision circuit (20) is provided which samples the back EMF induced into the stator winding (18) not being driven during single phase operation and initiates a restart cycle if the induced back EMF during single phase operation falls below a selected reference.

Abstract: A power converter (10) for supplying an output wave shape as a function of an oscillator (22) input utilizing a power output switching stage. A band limit generator (24) provides two reference signals (HL, LL) which define a band. The two reference signals are compared with a feedback signal from the load, in a detector (26). The detector (26) provides output signals for controlling the switching power output stage (20) to bring the feedback signal within the defined band.

Abstract: Apparatus and method for extracting the fundamental component of a complex waveshape (E.sub.T) and for determining the magnitude (V) and phase .theta. of the fundamental component are disclosed. The complex waveshape is converted into digital data relative to a reference signal (E.sub.R) and the in-phase (x.sub.1) and quadrature (y.sub.1) components of the fundamental component are determined by a graphical Fourier analysis of the digital data so that the magnitude and phase of the fundmental component relative to the reference signal (E.sub.R) can be determined.

Abstract: A pulse generator (2) provides output pulses which are phase-synchronized to pulses from an external trigger source (3) through the use of gated delay lines (13) used as clocks. Output mode versatility is achieved by storing desired pulse output waveforms in a random access memory device (26). Expanded output resolution is achieved via an arrangement of three independent counters (10, 20, 24). A fourth independent counter (40) is used for burst counting. A pair of converters (36, 38) are used to provide an output amplitude monitor/test capability.

Abstract: A reference signal generator is controlled by a central processing unit (20) via a multibus interface (22, 24, 26) and includes a plurality of signal channels (2, 4, 6, 8) selectively responsive to external signals (E.sub.c, E.sub.m) or internally generated signals (I.sub.c, I.sub.m2, I.sub.m4, I.sub.m6, I.sub.m8) for providing carrier (12), modulating (16), or amplitude modulated (34) output reference signals (E.sub.o2, E.sub.o4, E.sub.o6, E.sub.o8) having a variety of waveforms. One of the signal channels (8) is arranged to sum the outputs of the other channels. Each of the channels includes an output attenuator (44, 46, 48, 50, 52, 56) which imparts a relatively high resolution to the output reference signals (E.sub.o2, E.sub.o4, E.sub.o6, E.sub.o8) and a circuit (54, 60, 62, 64, 66) which adjusts the range of said output reference signals. A built-in test capability (FIG. 3) is provided which permits selection and testing of the output reference signals from any one of the channels (2, 4, 6, 8).

Abstract: A directional optical filter (41) is provided for a shadow mask color cathode ray tube (shadow mask CRT) (47) having a plurality of display elements on its face (49). Two sets of light absorbing planes are arranged at approximately 90.degree. from one another and serve to block light passing therethrough from an angle greater than a predetermined angle of viewing. In order to reduce moire patterns which would result from varying coincidences of the planes with patterns of phosphor dots on the shadow mask CRT (47), filter sheets (43, 45) containing the light absorbing planes are rotated so that at least one set of light absorbing planes is misaligned with a set of closely-adjacent phosphor dots by approximately 15.degree.. Advantages include the ability to provide a parallel light absorbing plane directional optical filter in association with a shadow mask CRT and an ability to control the range of preferred viewing angles to differing amounts substantially in the horizontal and vertical directions.

Abstract: A moveable pointer (15) on an indicator (11) is illuminated by use of at least one electroluminescent strip (21) which is mounted separately from the pointer (15). The pointer (15) is able to conduct light internally in such a way that light transmitted to one portion (23) of the pointer (15) illuminates another portion of the pointer (25). The electroluminescent strip (21) forms a light source for the pointer (15) so that the strip (21) may be mounted adjacent the pointer's hub (23) in order to provide the necessary illumination. This arrangement permits an indicator (11) to be illuminated with electroluminescent lighting in order that passive vision aids, such as night vision goggles, may be used, while providing sufficient illumination for the indicator's dial pointer (15).

Abstract: A unit can transmit driving torque from an input (32; 100) to an output (20; 118) shaft in a given rotational sense. Load torque of the same rotational sense, at the output shaft (20; 118), can cause that shaft to freewheel. The unit has a rotor (34; 104) arranged to be driven by the input shaft (32; 100). Also included is a hub (54; 132) coupled to the output shaft (20; 118) to rotate therewith. The unit also has a thrust device (46; 138). This thrust device (46; 138) is threadably and coaxially mounted on the rotor (34; 104) for running on the rotor (34; 104) and engaging the hub (54; 132).

Abstract: A multi-layer printed circuit board (21) has through holes (15-17) which are plated without conventional pads. This avoids circuit board rejections which would occur from cosmetic defects resulting from incomplete solder coverage of the pads and from pad lifting. In order to provide the through holes (15-17) with an adequate supply of solder during solder operations, wicks (45) are provided for each through hole (15-16) which is isolated from circuit traces (37, 38) on the exterior surface (33) of the printed circuit board (21). If the through hole (17) is connected to a circuit trace (38) on the exterior surface (33), then a connecting run (48) is used to provide wicking action in lieu of a tab (45).

Abstract: Apparatus is disclosed wherein the average period of a synthesized signal is a non-integral multiple of the period of a given signal. The apparatus is arranged so that a counter alternates its count between N and N+1, wherein N is a predetermined integer, in a predetermined pattern so that the average count approximates a rational non-integral value between N and N+1.

Abstract: A missile such as a projectile (11) carries at least two submunitions (13, 14) each of which has an active guidance capability. Each submunition (13, 14) has a forward end (21) which is slanted, creating an asymmetric shape for the submunition (13, 14). When the projectile (11) reaches a predetermined point in its trajectory, the submunitions (13, 14) are dispensed in a manner which causes the submunitions (13, 14) to acquire different flight paths. The guidance system on each submunition (13, 14) relies on the asymmetrical shape of the submunition (13, 14) to cause the submunition (13, 14) to precess about its center axis, thus creating an appropriate search pattern, such as a rosette search pattern. The asymmetric shape of the submunitions (13, 14) can also be used to control the flight path of the submunition (13, 14) after a suitable target has been acquired by the submunition's guidance system.

Abstract: A directional filter for ambient light is constructed from a thin base strip (2) of indeterminate length and having an opaque surface (4). The strip is wound into a roll (8) having a plurality of convolutions (10) and sections (12, 14, 16 and 18) are cut from the face of the roll. A pair of sections are disposed so that their convolutions are in an orthogonal configuration, and are sandwiched between a pair of glass plates (20, 22) having non-reflective outside surfaces (20A). Channels (24) are thereby provided, which impart directional characteristics to the ambient light.

Abstract: A capability for internal self-testing is provided for a test instrument in which data, in digital and in analog form, is sampled from various test points. A programmable delay generator is used to process some of the data and to provide strobes which control the data output and which control the sampling of data. This enables measurements to be made at a preselected time after the occurrence of a particular signal, thereby giving the system a capability of using the delay generator not only for providing comparisons of time functions but also for initiating test sub-routines.The self-test capability enables test equipment having time-dependent functions, such as test equipment for video displays, to be verified with respect to accuracy in order to establish a confidence test.

Abstract: A cathode ray tube vibration isolator is disclosed for mounting a cathode ray tube in a display for airborne applications wherein extreme vibrations and acceleration forces are experienced, while isolating the tube from the vibrations and acceleration forces that can cause tube breakage and mechanical distortion of the shadow mask and complex electron gun assembly in color tubes that cause display degradation. Four high damped silicone base elastomeric supports are located in a plane parallel to the face of the tube, which plane passes through the center of gravity of the tube. These four supports are spaced 90 degrees apart around the tube and are fixed to both the magnetic shield of the tube and to the walls of the case in which the tube and its associated circuitry are mounted to provide vibration isolation.

Abstract: A hermetically sealed drive unit is provided in which a rotationally fixed face gear (27) is mounted within a spherical bore (29) on a bellows (47) so as to cause teeth (31) on the fixed face gear to (27) successfully engage teeth (24) on a rotatable face gear (23). The face gears (23, 27) have different numbers of teeth (24, 31) and therefore must rotate with respect to one another when the teeth (24, 31) engage each other successfully. The rotatable face gear (23) is mounted on one shaft (17), and another shaft (21) is provided with a cam (39). The shaft (21) with the cam rotates in order to cause the rotationally fixed face gear (27) to wobble within the spherical bore (29), causing the teeth (31) on the rotationally fixed face gear to engage the teeth (24) on the rotatable gear (23) in succession.

Abstract: A disconnection coupling (11) is provided for installation between the input shaft (41) of an accessory and an engine to which the accessory is mounted. An input member (20) of the coupling (11) is connected to the engine in lieu of the accessory's input shaft (41). This provides engine power to the input member which can be selectively transferred to the accessory's input shaft. An intermediate member (30) is rotationally connected to an output member (40) which, in turn, receives the accessory's input shaft (41). The intermediate member (30) is able to be axially displaced with respect to the output member (40), while a spline joint (35) maintains the rotational connection between the intermediate and output members (30, 40).