System Integration, Laboratory 
and Field Work

In addition to the software for the Fast Cryogenic Array Spectrometer (FCAS), I have worked on the instrument and its peripherals.  The instrument hardware consists of three modules:  a vacuum/cryogenic/optical dewar, a "telescope" rack, and an "observer's" rack.  The observer's rack contains a Sun computer which controls the whole affair and sits in the observation room of an observatory when in use.  The telescope rack contains the equipment necessary to operate the dewar, and sits next to the telescope when in use.  The dewar attaches to the focal plane of a telescope (it can adapt to many telescopes, such as the NASA IRTF or Lowell 72-inch). 

The two equipment racks are aircraft-certified, and are coupled by optical fiber to eliminate signal degradation and radiation into the observatory environment.  These fibers carry control and signal information via RS-232 serial protocol and custom protocols for the infrared array electronics.

I assembled the racks with all peripherals, made custom cables, and built the fiber cable assembly, which consists of five active pairs with optical modems at each end.  I also constructed housings for this equipment so that it could be rack-mounted.  In addition, I configured the UNIX controller with all custom and commercial software and security precautions.  Below are clickable images of the racks.

racks with coiled fiber cable optical modem assembly on telescope rack

Calibration lamps (Argon, Krypton, Xenon, and continuum) are used to calibrate the instrument to known spectral features.  Some of these lamps are activated by an intelligent controller which requires a special signal from the host computer in the observer's rack.  The host computer communicates with the telescope-rack-mounted intelligent controller via fiber.  I built a current-limited voltage source which is used to generate this special signal for lamp activation.  I also constructed "through-hull" connections and cables for the calibration apparatus.

During two years of instrumentation development I have assembled and disassembled the dewar many times; it is a complex operation which takes at least two days.  The work is performed in low-level clean room conditions with electrostatic precautions.

I have also traveled with the instrument on field operations and am accustomed to operating vacuum-cryogenic equipment and large optical telescopes.