Abstract: AC and/or DC testing of an optoelectronic device at the wafer level. In one example embodiment, a method of testing one or more devices at a wafer level includes generating a test signal; supplying the test signal to a single device on a wafer; providing an output of the single device to each of a plurality of devices on the wafer by way of a common electrical connection between the single device and the plurality of devices; providing an output of each of the plurality of devices to a corresponding return connection by way of electrical connections between the plurality of devices and the plurality of return connections; and receiving return currents from each of the return connections.

Abstract: In an internal combustion engine wherein the air inlet ports are opened and closed directly by the reciprocating movement of the piston, the crankshaft is laterally offset from the central plane common to the longitudinal axes of all of the cylinders. This results in a substantial increase in the power output of the engine.

Abstract: In combination with an internal combustion engine and an air compressor, for use in an aircraft, the compressor providing compressed air to the engine's air inlet, there is provided a variable overboard bleed valve. The bleed valve is operated by a valve controller which controls the position of the bleed valve in response to changes in engine operating conditions. This permits maintaining optimum compressor operation over a wide range of engine operating conditions without exceeding the critical pressure of the compressor, so as to avoid surge. The controller can be preferably linked to the propeller governor and the throttle control for the aircraft, so as to move in response to movement of the governor and throttle control.

Abstract: A conventional aircraft having horizontal stabilizers and hinged elevators, which is controlled, preferably, through push-pull rods, is provided with a dynamic torque (bob) weight connected to a rotating member, in the direct line of control to the elevator surfaces. The torque member is located in the nose portion of the aircraft with its center of gravity angled up from 20.degree. to 50.degree. when the elevator surfaces are in the neutral position. The torque member is also mounted in a flexible manner to isolate it from horizontal tail vibrations, or flutter.

Abstract: An air conditioning system for powered aircraft is provided wherein a refrigerant compressor is located immediately adjacent to the alternator at the right forward portion of a horizontally opposed aircraft engine. The compressor is mechanically driven indirectly from the main bulkhead/starter ring gear assembly through a twin sheaved pulley on the alternator. The air conditioning system also is provided with two sets of inlet ports for cooling air flow to a refrigerant condenser. One set of inlet ports accepts ram air when the aircraft is airborne. The second set of ports is closable and accepts air when an interior intake impeller is activated. The engine-compressor-alternator combination fits within an aerodynamic cowling having no greater frontal area than one required for the engine without the compressor.