Abstract: A testing fixture which facilitates inexpensive, high-speed dynamic testing of electronic devices without subjecting the electrical leads of the devices to damage includes a first carrier plate having a plurality of electrical contacts associated with respective electrical leads of the electronic device which is to be tested, the first carrier plate including electrical conductors electrically connected with the electrical contacts for supplying power to the electronic device and for monitoring signals from the electronic device during testing, and a second carrier plate secured to the first carrier plate, the second carrier plate including abutment surfaces which overlie the electrical contacts on the first carrier plate to retain the electrical leads on the electronic device between the electrical contacts on the first carrier plate and the abutment surfaces on the second carrier plate during testing of the electronic device.

Abstract: Hydrostatic bearing vibration test apparatus in which the pillow block housing is opertively coupled to the workpiece by an oil film while the carriage blocks are fixed to the workpiece and the bearing shaft, the housing being supported on flexible bolts permitting two degrees of freedom in the bearing appartus.

Abstract: A driver bar assembly for coupling together a shaker head 12 and a slip plate 34 carrying a test piece 60 to be vibration tested, the assembly comprising a driver bar 14 having a laterally extended locus of intersection (L-L, P-P) with the slip plate in the slip plate plane of test movement, and fastener means comprising a rigid pin 50 extending laterally within the locus of intersection in slip plate and bar interconnecting relation for transmission of shaker head vibration to the slip plate through the pin.

Abstract: Vibration fixture apparatus and method of use for high volume testing of circuit boards and the like is provided comprising a frame peripherially surrounding the board and a shimming structure which is hydraulically actuated to bind against the board and frame selectively for faithful transmission of vibration energy from a vibration source through the frame to the board to be tested.

Abstract: An electrooptical system and technique for direct quantitative measurement of the mass concentration of monodisperse aerosols by means of filling an enclosed chamber with a cloud or a sequence of separate clouds of essentially transparent and spherical, aerosolized particles or droplets of known density and known or selectively controlled particle size. While within the confines of the chamber the cloud, or each of the sequence of clouds, of aerosolized particles is maintained in a homogeneous condition and irradiated with a beam of high-intensity and constant wavelength irradiation selected to possess a wavelength to particle size ratio wherein attenuation of the irradiation will be almost exclusively, if not nearly entirely, attributable to optical scattering.

Abstract: Two axis shaker vibration of a slip plate is achieved by use of angularly disposed shakers of novel design, each being provided with an armature cantilevered from the slip plate and free to laterally translate at the same time they drive the slip plate. Pivoting moments are converted to linear motion by a torsionally stiff flexure support for the slip plate.

Abstract: A torsionally stiff flexure support for the slip plate in a vibration apparatus is provided permitting predetermined linear motion along the axis of vibration by longitudinal bending of the flexure, but by virtue of its torsional stiffness blocking pivoting movement about the center axis of the slip plate.

Abstract: A vibration test, bearing table apparatus comprising a support block having a surface slideably supporting a test piece-carrying slip plate intended to oscillate along a single predetermined axis at a desired test frequency responsive to shaker head driving of the slip plate is provided, with an improvement comprising means within the locus of sliding engagement including a cooperating shaft and bearing assembly distributively coupling the slip plate and support block together in a manner maintaining the test piece on a single degree of freedom path coincident with the test axis, whereby tendencies of the driving force to impart spurious cross-axis pitch, yaw and roll test piece motion relative to the intended test axis are blocked.

Abstract: Hydrostatic bearing apparatus adapted to mount a shaker-coupled, dimensionally temperature dependent test piece for vibratory oscillation along a predetermined test axis. The apparatus comprises a support block having a compliant section defining a bore, a shaft axially journaled in the bore and defining therewith a bearing locus paraxial with the test axis. Bracket means is provided securing the test piece to the shaft beyond the locus for bearing-guided test axis oscillation, the bearing locus being test axis paraxially bodily displaceable responsive to displacement of the compliant section in test piece dimensional change accommodating relation.

Abstract: A slip plate assembly is provided for shaker-head generated vibration testing of a test piece being exposed to thermal cycling between preselected test temperature extremes in a closed environment. The assembly comprises a pair of opposed plate elements, a first plate element being beyond the closed environment and a second plate element exposed to test temperatures within the closed environment. Pin means is provided defining a singular locus of vibration transmitting connection between the first plate and the second plate in dimensionally temperature-responsive relation.

Abstract: Vibration testing apparatus in which the driver bar interconnecting the slip plate and shaker head in vibration transmitting relation supports the slip plate more closely adjacent the shaker head and in cantilevered fashion, opposite the locus of free-sliding engagement of the slip plate and its support block, and free of such locus.