Abstract: An arrayable loudspeaker system having a horn-loaded high frequency compression driver and a low frequency cone driver radiates acoustic energy from a focal point in a polar radiation pattern having amplitude and phase and includes a signal conditioning circuit for amplitude equalization and phase correction. The horn of the system's horn-loaded compression driver is designed in cooperation with the signal conditioning circuit such that the focal point of the loudspeaker system is substantially frequency independent over the operating frequency range of the loudspeaker system and such that over this operating frequency range the loudspeaker's focal point remains substantially fixed in space. Any two or more of such loudspeaker systems can be arrayed by aligning them in respect to their frequency independent focal points and by rotating the loudspeakers about an axis passing through the aligned focal points to obtain a desired coverage.

Abstract: The improvement in a control circuit for the operation of pneumatically propelled vehicles consists of a propulsion duct formed by a guideway (1) and power propulsion units (3) with flow control valves (4) located at intervals along the guideway (1). Atmospheric valves (2) are located at specific points along the guideway (1), opening and closing the duct to the atmosphere, and the section isolation valves (6) are positioned in such a way as to isolate adjacent blocks of the guideway (1) and at the same time to maintain the functioning of the propulsion circuit in the other blocks. The atmospheric valve (2) is coupled to an aperture (11) in the guideway (1) and consists of a butterfly valve.

Abstract: An indirect luminaire having a housing with a top opening and a light source in the housing is provided with an exposed lens reflector system positioned over the top opening of the housing for receiving and redirecting source light from a position above the light source. The lensed reflector system includes an outer refracting lens element having a lens surface observable from below the luminaire and a substantially diffuse reflector substrate for the lens element. This system produces a light distribution pattern substantially governed by the internal reflection and refraction characteristics of the lens element and controlled brightness characteristics on the observable lens surface substantially governed by the diffuse reflection characteristics of the reflector substrate. A lens tower is suitably provided for holding the lensed reflective system in its operative position over the top opening of the luminaire housing.

Abstract: A test socket for an IC device has relatively thin contact interface wall having an array of double-ended pogo pins. The double-ended pogo pins provide resilient spring-loaded contacts for the I/O contacts of an IC device held in the socket as well as for the circuit contacts of a PC board to which the socket is mounted.

Abstract: A connector system (20) connects a leadless integrated circuit (IC) device (22) to a printed circuit (PC) board (24) by means of a contact array (26). The contact array (26) connects input-output (I/O) contacts on the IC device (22) to corresponding circuit contacts (28) on PC board (24). The contact array (26) is a generally thin, flexible and rectangular shaped element that is sandwiched between the PC board (24) and the IC device (22). The contact array (26) has a plurality of square cells (30) that are each a portion of the array (26) and are formed from a planar body (32) of a suitable conductive material, such as beryllium copper, sandwiched between suitable insulating films, formed from polyimide. Each cell is divided into a first pair (34) of contact elements (36) extending above the plane of the body (32) and a second pair (38) of contact elements (36) extending below the plane of the body (32).

Abstract: A test kit for measuring vapor emission from a concrete floor or other planar surface prior to installing a flooring material includes a relatively rigid dome-shaped cover having an outer bottom rim for seating with the planar surface to be tested when the cover is placed on the surface over an uncovered container of moisture absorptive material such as calcium chloride. The test kit further includes a weight ring that is removably placed onto a shoulder portion of the cover located at the cover's outer bottom rim. Placement of the weight ring on the dome-shaped cover during tests acts to hold the outer bottom rim of the cover in seating contact with the test surface. The test kit is easy to use and provides for reusable components. It can also be used without leaving a residue on the test surface.

Abstract: A task light shelf system provide a task light having an elongated housing with a planar top wall structure that acts as a shelf surface. The housing of the task light has sufficient structural strength to carry loads on the shelf surface and is supported over a task area by means of angle brackets that attach to attachment slots formed in the top wall of the task light. Extended shelf surfaces can be provided by means of insert elements and angle brackets having extended attachment arms, which attach to the extended arms of the angle brackets. The insert elements can be optionally closed channel members to provide wire or cable channels behind the task light.