Abstract: A method of repairing a rotor blade, for example on an integrally bladed rotor, includes preparing a surface on a damaged area of the blade. The blade has first and second airfoil surfaces adjoining the prepared surface that are spaced apart a distance. An edge of a patch abuts the prepared surface to provide a weld interface defining a welding plane. First and second cover sheets respectively overlap the first and second airfoil surfaces. The first and second cover sheets adjoin the edge and the first and second airfoil surfaces. The blade, patch and first and second cover sheets are welded along the welding plane providing a welded joint at the weld interface. The first and second cover sheets are substantially unsecured to the first and second airfoil surfaces subsequent to the welding operation.

Abstract: An assembly for use in a turbine of a gas turbine engine includes a turbine disk and a shaft. The turbine disk comprises a superalloy. The shaft is friction welded to the turbine disk at a shaft interface substantially adjacent the turbine disk.

Abstract: Disclosed is a sensor assembly including a port, which may support one or more headers, and a header affixed to the port by a weld joint. The header may support a sensor, such as a pressure sensor. A backing ring protects the assembly from damage that may be caused by welding.

Abstract: Disclosed is a method of laser shock peening an aluminum alloy fan airfoil to improve its resistance to failure by notched fatigue. In one example, the airfoil is made from 7255 aluminum alloy. The laser has a power density of at least 10 GW/cm2 (220×109 BTU/hr·in2) and a pulse width of <50 ns to produce a shock peened layer extending a depth of 0.030-0.040 inch (0.8-1.0 mm) beneath the object surface.

Abstract: A method of repairing a rotor blade, for example on an integrally bladed rotor, includes preparing a surface on a damaged area of the blade. The blade has first and second airfoil surfaces adjoining the prepared surface that are spaced apart a distance. An edge of a patch abuts the prepared surface to provide a weld interface defining a welding plane. First and second cover sheets respectively overlap the first and second airfoil surfaces. The first and second cover sheets adjoin the edge and the first and second airfoil surfaces. The blade, patch and first and second cover sheets are welded along the welding plane providing a welded joint at the weld interface. The first and second cover sheets are substantially unsecured to the first and second airfoil surfaces subsequent to the welding operation.

Abstract: A power combiner including a plurality of phasing transmission lines (122) supporting a set of amplifiers (104) coupled thereto, and a plurality of matching transmission lines (124). The set of amplifiers (104) having a selectable number of amplifiers between a minimum and a maximum value. Each of the matching transmission lines (124) is coupled to one of the phasing transmission lines (122) at one end and coupled to a common node (126) at the other end. Each of the matching transmission (124) lines has a substantially equivalent characteristic impedance determined according to a function of the minimum and the maximum number of amplifiers in the set of amplifiers (104).

Abstract: A feed forward amplifier network (100) employs a method (300) and apparatus for reducing distortion contained in an output signal (142) of an amplifier circuit (101). A modulator (118, 120) modulates (303) an input signal (141) of the amplifier circuit (101) with a reference modulation. The amplifier circuit (101) amplifies (305) the modulated signal, introducing nonlinear distortion in the process. A modulation determination circuit (107, 109, 115) determines (307) the reference modulation in the amplified signal and provides the determined modulation to an adjustment circuit (105). The adjustment circuit (131,133, 135) adjusts (309) a characteristic of the determined modulation in response to a control signal (153,155) and combines (137, 311) the adjusted modulation with the amplified signal (142) at the output of the amplifier circuit (101) to produce a corrected signal (151).

Abstract: A method and apparatus is provided for controlling peak envelope power level in a power amplifier (PA) (10). The method includes the steps of measuring (101) a first peak envelope power value of an input of the PA during a first time period, comparing (102) the first peak envelope power value with a threshold value, and introducing a phase change (103) into a selected signal of a plurality of signals being amplified by the PA when the first peak envelope power value exceeds the threshold. The method further includes measuring (104) a second peak envelope power value during a second time period, comparing (105) the first and second peak envelope power values, and reversing (106) the phase change to the selected signal when the second peak envelope power value exceeds the first peak envelope power value.

Abstract: A simulcast broadcast uses digital signal processing techniques to scale pulse coded modulation samples of a signal for broadcast. Samples are adjusted to fully utilize all quantization levels representable by an 8-bit word. Time delay is adjustable using digital techniques by writing and reading data into and out of a RAM. Signal amplitude is adjustable by multiplying samples by a numeric factor. A computer can be used to adjust processing, delay and amplification of the digital signal processor.