Date: Wed, 21 Jan 1998 21:19:31 -0500 (EST)
From: skrutski@north.phast.umass.edu (Mike Skrutskie)

Rae has made  a number of changes on the mountain which, in
principle, should not affect the data, but people should
be on the lookout starting tonight (22 Jan UT).

He removed a resistor on one of the ADC boards.  The
swaping of these boards was previously associated
with a 1 pixel jump in band-to-band pointing.
The removal of the resistor should have no effect, however...

Also, he exercised the gain and offset pots on the ADC boards.
These are minor trim adjustements and should only produce
tiny changes
in the system gain, probably at an undetectable level.


Date: Wed, 21 Jan 1998 23:44:33 +0000 (GMT)
From: Rae Stiening 

Camera lower fiber box:
        Added heat sinks to two Xilinx memory address decoders and
                3.3v regulator.
        Removed C124 to speed boot up.
        Cleaned dust from box.
        Removed U23 (seprom) #44 and replaced it with "TEST".  This
                seprom is not used in normal operations.
        Wrapped up LFB-Raptor cables to reduce electrical pickup.

Camera SV21 card
        SV21 Serial F35988 which was in service was replaced with
                SV21 Serial F38103.
        Operating system updated from Gatir 1.10 to 1.11.
        
J-Band ADC card (serial #2)
        No changes. 
        Does not have paralleled gates.
        Has pots. Pots were exercised to make sure contacts are clean.

H-Band ADC card (serial #6)
        Removed 2k pull up resistor
        Has parallel gates which were not changed.
        Does not have posts

K-Band ADC card
        No changes
        Does not have paralleled gates.
        Has pots.  Pots were exercised to make sure contacts are clean.

Camera Upper Fiber Board
        Screwed 3.3v regulator to board with thermal compound to
                improve cooling.        

Script (NI2MASS) software changes
        Checked contents of NI2MASS/Current against floppy disk archive
                "Hopkins archive 11/14/97"
        No change for following files:
        script.c,ctdir.c,tdir.c,script.ini,script.lst,mks.bat,purge,bat
        chkpurge.bat,abort.txt,camboot.sct,camwake.sct,dark.sct,focus.sct,
        newlog.sct,point.sct,preset.sct,shutdown.sct,start_up.sct, and
        view.sct

        The following files had a 499mS wait ahead of store_data_d removed
                on 11/20/97: cal.sct,survey.sct,tst.sct, and view.sct.
        It is correct to remove this 499mS wait because the changes to
                the weather station routines in SCRIPT could not have been
                related to this delay.

        Checked to see that executable script.exe is binary identical to
                a today compile from script.c.  It was.

Software changes to Script.c today:
        An explicit raptor command to disable raptor interrupts was added
                to the initialization routines.  Change is documented
                in Script.dif attached to this e-mail.
Software change to Camboot.sct today:
        A dummy serial command to clear any excess characters on bootup
                was added.
        A hard reset to the SV21 during bootup was added to the operator
                instructions.  Change is documented in Camboot.dif
                attached to this e-mail.

TCS changes:
        A logic error in the mirror cover open detection circuitry was
                corrected.  Until today when either mirror cover was open
                TCS would report mirror covers open.  After today BOTH
                covers must be open before TCS will report covers open.
                This change is not in the hardware loop which the cover
                actuators use to detect full open.  

        The startup script will now hang on mirror covers open check if
                both covers are not open.  The operator will have to
                investigate why the switchs are not closed before
                proceeding.