Abstract: A system and method for measuring the frequency response of a system under test using a single swept-frequency chirp signal. A tapered chirp-frequency test signal is created with a bandwidth defined by first and second frequencies. The test signal is routed to a calibration path, and the output of the calibration path is routed to a digitizer. The output of the calibration path is digitized, and a Fourier transform of the calibration path output is generated. The test signal is then routed to a test system, and the output of the test system is coupled to the digitizer. The output of the test system is digitized, and a Fourier transform of the test system output is generated. A normalized frequency-domain representation of the test system created by dividing the Fourier transform of the test system output by the Fourier transform of the calibration path output.

Abstract: A system and method for measuring the frequency response of a system under test using a single swept-frequency chirp signal. A tapered chirp-frequency test signal is created with a bandwidth defined by first and second frequencies. The test signal is routed to a calibration path, and the output of the calibration path is routed to a digitizer. The output of the calibration path is digitized, and a Fourier transform of the calibration path output is generated. The test signal is then routed to a test system, and the output of the test system is coupled to the digitizer. The output of the test system is digitized, and a Fourier transform of the test system output is generated. A normalized frequency-domain representation of the test system created by dividing the Fourier transform of the test system output by the Fourier transform of the calibration path output.

Abstract: A wafer handling apparatus having a variable pitch includes a supporting surface (12) for holding a boat (14) in a predetermined location. An elevator mechanism (20) is operable to move upward through the boat to lift wafers (16) upward into intermediate restraining combs (24) and (26). Combs (22) are disposed on the elevator mechanism (20) for holding the wafers (16) on the edges thereof. The combs (22) can have the pitch thereof varied by the operation of a cylinder (56). The combs (22) have two rotating brackets (42) and (40) disposed on the sides thereof. The brackets (42) and (40) are pivoted on an elevator bracket (28) at points (44) and (46). When the lower bracket (40) is reciprocated upward by the cylinder (56) and the associated rod (54), the space between the combs (22) decreases.