SPECTRUM ASTRO, INC.
                       HIGH ENERGY SOLAR SPECTROSCOPIC IMAGER (HESSI) PROGRAM
                                    PRODUCT FUNCTION SPECIFICATION
                                          COARSE SUN SENSORS
                                        CONTRACT NO. PPB005884
                          SPECTRUM ASTRO PROPRIETARY DOCUMENT
          THIS DOCUMENT CONTAINS SPECTRUM ASTRO PROPRIETARY INFORMATION.   RECIPIENT, BY
          ACCEPTING THIS DOCUMENT, AGREES THAT NEITHER THE DOCUMENT NOR ANY INFORMATION
          CONTAINED WITHIN IT SHALL BE REPRODUCED OR TRANSFERRED TO OTHER DOCUMENTS NOR
          USED OR DISCLOSED TO OTHERS FOR MANUFACTURING OR ANY OTHER PURPOSES EXCEPT AS
          SPECIFICALLY AUTHORIZED IN WRITING BY SPECTRUM ASTRO.
                                 PREPARED BY:
                             SPECTRUM ASTRO, INC.
                              1440 N. Fiesta Boulevard
                               Gilbert, Arizona   85233
                                CAGE Code 0T9D1
                             INITIAL RELEASE DATE
                               1 SEPTEMBER 1998
                                                                                           1110-EW-T10164
                                                 SPECTRUM ASTRO, INC.
                           HIGH ENERGY SOLAR SPECTROSCOPIC IMAGER (HESSI) PROGRAM
                                           PRODUCT FUNCTION SPECIFICATION
                                                  COARSE SUN SENSORS
                                                 CONTRACT NO. PPB005884
             REV     RELEASE DATE            BRIEF DESCRIPTION/REASON FOR CHANGE                   EFFECTIVE
                                                  REVISION SUMMARY                                    PAGES
              -      1 September 1998   Initial release                                                 All
                                     REVIEWED BY:
                                                     CONFIGURATION/DATA CONTROL, DAVE MAIDEN                 DATE
                                     APPROVED BY:
                                                     SUBCONTRACT MGT., DONNA GREENWOOD                       DATE
                                     APPROVED BY:
                                                     QUALITY ASSURANCE, JEFF SQUIRES                         DATE
                                     APPROVED BY:
                                                     ENGINEERING, GLENN CREAMER                              DATE
                                     APPROVED BY:
                                                     SYSTEM ENGINEERING, JOHN JORDAN                         DATE
                                     APPROVED BY:
                                                     PROGRAM MANAGER, JEFF PREBLE                            DATE
                                                                                     1110-EW-T10164          REV -
                                                SPECTRUM ASTRO PROPRIETARY DATA
                              USE, DUPLICATION, AND DISCLOSURE OF THIS INFORMATION IS RESTRICTED ON TITLE PAGE
                                                             ii                      1 SEPTEMBER 1998
                                                                                     1110-EW-T10164
                                           SPECTRUM ASTRO PROPRIETARY DATA
                          USE, DUPLICATION, AND DISCLOSURE OF THIS INFORMATION IS RESTRICTED ON TITLE PAGE
                                                      iii
                                                                                     1110-EW-T10164
                                             TABLE OF CONTENTS
                                                                                               PAGE
          1.  INTRODUCTION...............................................................................................................................................0
            1.1 Scope..............................................................................................................................................................0
            1.2 Classification..................................................................................................................................................0
          2.  APPLICABLE DOCUMENTS...........................................................................................................................0
            2.1 Documents......................................................................................................................................................0
            2.2 Precedence......................................................................................................................................................0
          3.  REQUIREMENTS..............................................................................................................................................0
            3.1 Item Definition...............................................................................................................................................0
              3.1.1 Physical Description................................................................................................................................0
              3.1.2 References...............................................................................................................................................0
              3.1.3 Interfaces.................................................................................................................................................0
              3.1.3.1 Physical Interfaces................................................................................................................................0
              3.1.3.2 Connectors and Pin Assignments.........................................................................................................0
              3.1.3.3 Electrical Interface................................................................................................................................0
              3.1.3.3.1 Electrical Power Interface..................................................................................................................0
              3.1.3.3.2 Command and Data Interface............................................................................................................0
            3.2 Characteristics................................................................................................................................................0
              3.2.1 Performance Characteristics....................................................................................................................0
              3.2.2 Physical Characteristics...........................................................................................................................0
              3.2.3 Reliability................................................................................................................................................0
              3.2.4 Environmental Conditions.......................................................................................................................0
            3.3 Design and Construction................................................................................................................................0
              3.3.1 Electromagnetic Radiation......................................................................................................................0
              3.3.2 Life Requirements...................................................................................................................................0
          4.  QUALITY ASSURANCE PROVISIONS...........................................................................................................0
          5.  PREPARATION FOR DELIVERY.....................................................................................................................0
                                      TABLE OF CONTENTS (CONTINUED)
                                                                                               PAGE
                                           SPECTRUM ASTRO PROPRIETARY DATA
                          USE, DUPLICATION, AND DISCLOSURE OF THIS INFORMATION IS RESTRICTED ON TITLE PAGE
                                                      iv