III. Stellar photon fluxes at wavelengths near 2000 Å

Abstract

11. The telemetry record The output of each photometer is sampled by the telemetry switch some 170 times per second and the photometer orientation changes by approximately |° between successive samples. The passage of a star across the centre of the field of view of a photometer will be shown on the telemetry record by five or six points displaced from the zero level. If the star does not cross the field diametrically then fewer displaced points will be shown. The displacements of the first and last of such a sequence of points will be small and they may not be readily seen. Displaced points will also occur as the result of noise in the photometers and the telemetry system. The signals can be distinguished from the noise in a number of ways: (1) By the grouping of signal points. (2) By the correlation of signal points with the passage of stars across the field. This is discussed further in § 12. (3) By comparison of telemetry records made at receiving stations separated by a large distance. Records made at the Woomera range-head and at Mirikata 100 miles down-range, are available for this purpose.