This paper discusses the development of the GSU speckle camera system. Primary consideration was given to stability, reliability, observing efficiency, portability and sensitivity. The optical and mechanical design allows the high gain, two-dimensional detector to be used for both field acquisition and speckle recording. The detector package consists of a proximity focus, dual microchannel plate intensifier, fiberoptically coupled to a two-dimensional CCD operating at standard video rates. The camera head control electronics are based on a 6809 microprocessor. The microprocessor based electronics controls the various motor driven optical components for the two observational modes (speckle and acquisition), adjusts the atmospheric dispersion compensation elements, positions the narrow bandpass optical filters, controls the field integration time, controls the number of recorded data fields per object and handles various other house-keeping functions. A separate micro-computer stores the observing program on floppy disks and calculates the position settings for the atmospheric dispersion compensation elements. The raw observational data is recorded, real time, on a special video cassette recorder. The video tape is positioned by stepper motors and tape position is servo controlled relative to the video read heads to maximize stability and minimize guard band noise in the "still frame" read mode. The present system concept incorporates a near real time digital autocorrelator for processing the video taped data.
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