Run II Power Pan
                     --------------------




                     Power Pan Front Panel
                   -------------------------

                                              Original Version  10-MAR-1997
                                           Most Recent Version  13-OCT-1997


Please drill the holes and slots in the blank front panels as shown in
the attached drawings.

The following table is the "X-Y" centers of the various Front Panel
components.


           Component               XY Center Location
      -----------------------    ----------------------
        Fan                         4.000"     2.600"
                                   15.000      2.600

        Large Pilot Light           8.300      4.000

        3 Pole Switch               8.300      0.800
          location of the
          lower center screw


        Small Red Pilot Light      10.700      4.200
                                   10.700      3.400
                                   10.700      2.600
                                   10.700      1.800

        Test Jacks                 11.700      4.200
                                   11.700      3.400
                                   11.700      2.600
                                   11.700      1.800
                                   11.700      1.000

        Small Switch               10.700      1.000



There are 19 blank front panels that need to be prepared as shown in
these drawings.

None of these components are mechanically connected to each other, so
placement tolerance is not super important.




  Modification of the  Astec  VS3-D1-D1-20  Spectrum  Power Supplies
 --------------------------------------------------------------------

                                                      Rev. 8-OCT-1997

Called Ken Miller at Astec (phone 760-757-1880) to ask how to "de-
parallel"  the two 240 Amp 3.3 Volt supplies in the  VS3-D1-D1-20
module, i.e. make it into a  VS3-D1-D1-00  module.

  1. Remove the copper plates that strap the outputs together.

  2. Remove jumpers JP5 and JP7 from the backplane board inside of the
     supply.  You actually only need to remove the JP5 jumper cap.  You
     can do this from the outside.  With the panels of the  D1  modules
     facing you, look at the right hand module.  Just to the left of this
     module's 10 pin Molex connector you can see jumper cap JP5.  You can
     reach in, pop it off, and shake it our.  Remove JP7, which is
     located in a similar with respect to the left hand D1 module.  These
     are the only two black jumper caps that should be installed on the
     backplane boards in the immediate vicinity of the two D1 modules.

  3. If you want to "re-parallel" the two D1 module, re-install the
     output straps and use the "single wire parallel" pins on the Molex
     connectors on the D1 modules.


        Input          Left                Right
       Module     Double Module        Double Module

                   P4       P6          P8        P10
                 pin 3     pin 3      pin 3     pin 3

                   X          X             X          X
                   |          |             |          |
                   |          |             |          |
                   X          X             X          X     Jumper
                  JP8        JP7           JP6        JP5     Caps
                   X          X             X          X
                   |          |             |          |
                   |          |             |          |
                   +----------+----X  X-----+----------+
                                   JP12
                                 Soldered
                               Jumper Wire







                Sequencing of the Power Supplies
              ------------------------------------

                                              Original Version  19-JUNE-1998
                                           Most Recent Version  19-JUNE-1998