Mauna Loa Solar Observatory Observer's Log 
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Sun Apr 23 16:50:39 GMT 1995
Year: 95  Doy: 113
Observer: yasukawa   console      Apr 23 16:40

WEATHER COMMENT: Sun Apr 23 16:50:58 GMT 1995
Cold, clear, no wind at this time.  Cloud bank to east quite high.
Temp=34F, relative humidity 70%.


COMMENT: Sun Apr 23 16:52:13 GMT 1995
Island-wide power outage yesterday evening.  Internet connection still out,
as evidenced by slow startup of Sparcstation this morning.


LOW-L COMMENT: Sun Apr 23 16:53:41 GMT 1995
Lowl was restarted and taking data on unit 0.  Since there were numerous
problems yesterday, and the data has already been overwritten at the
beginning of the tape, I decided to just let it continue on L00224.

Sun Apr 23 16:55:59 GMT 1995: Patrol Start

DPMON COMMENT: Sun Apr 23 16:59:07 GMT 1995
Optics runaway.  Resetting manually.

Sun Apr 23 17:01:43 GMT 1995: Patrol Start

COMMENT: Sun Apr 23 17:05:48 GMT 1995
Network check with ping command indicates connection between MLO
router on mountain and MLO at FB is down.


DPMON COMMENT: Sun Apr 23 17:37:59 GMT 1995
Daystar runaway, reset Plessey.

Sun Apr 23 17:40:10 GMT 1995: Patrol Start

DPMON COMMENT: Sun Apr 23 17:40:18 GMT 1995
Had to use manual control to reset.  Objective had run away also.


MKIII COMMENT: Sun Apr 23 17:44:53 GMT 1995
Vdiff check shows streaking occurring.  Will try an ALLFRESH 
attempt to see if problem is with correctors.


MKIII COMMENT: Sun Apr 23 17:51:40 GMT 1995
By applying ALLFRESH to CORONA trace, streaking clears up briefly.
Check of VDIFF indicates no fix.

Sun Apr 23 18:02:05 GMT 1995: Calibration

MKIII COMMENT: Sun Apr 23 18:12:36 GMT 1995
Swapped AN4 card (A/D converters) in channel 2 analog (micro 0)
with a known good spare.


MKIII COMMENT: Sun Apr 23 18:22:15 GMT 1995
Streaking still present.  Swapping AN4 back.  Swapping AN2 (MDACs)
as a next step.





MKIII COMMENT: Sun Apr 23 18:37:47 GMT 1995
That may have been it!  Replaced AN2 card in Analog chan 2 (Micro 0)
with a known-good spare.  That cleaned up the streaking.  Will run
for a while to make sure that cycling the power is not the
cause of the "fix".  Upon close examination of the "faulty"
AN2 board, one of the filter capacitors between the ground plane
power and ground is very fuzzy with corrosion, probably from
leaking electrolyte.


MKIII COMMENT: Sun Apr 23 18:48:08 GMT 1995
Latest VDIFF with first scan indicates that streaking my be returning.
This indicates that the cycling of the power may have temporarily
fixed the problem.
At this time the streaking signature is very subtle so I will
run a bit longer before attempting other things.

Sun Apr 23 19:01:59 GMT 1995: Calibration

MKIII COMMENT: Sun Apr 23 19:36:15 GMT 1995
At this point, methinks that the subtle streaking might just
be a touch of paranoia and the sky getting a bit noisy.
Will keep up vigilance.


COMMENT: Sun Apr 23 19:47:25 GMT 1995
Opening top of dome.

Sun Apr 23 20:02:01 GMT 1995: Calibration

MKIII COMMENT: Sun Apr 23 20:13:17 GMT 1995
Inspected suspect AN2 board further and found that negative lead
to filter capacitor broke off at touch underneath all the
corrosion.  Removed capacitor and replaced it with closest substitute
available, a 10mfd-35V tantalum.  Will need to test board before
adding it to spares inventory.


MKIII COMMENT: Sun Apr 23 21:01:37 GMT 1995
Sky very noisy.  Stopping MKIII exabyte while trying a couple 
of tests to see if streaking fix worked.


WEATHER COMMENT: Sun Apr 23 21:35:52 GMT 1995
In orographic clouds.

Sun Apr 23 21:37:04 GMT 1995: Patrol End

MKIII COMMENT: Sun Apr 23 21:42:29 GMT 1995
Tried looking at VDIFF comparing two opal-in scans.  That subtle
streak/noise is present in outer 1/4 of scan.  Tried swapping
the analog corrector memory cards and repeated opal-in/VDIFF
test and results were the same.  Outer noise may be an effect
of detector misalignment, pixel noise in the outer pixels, or
some combination of alignment and corrector values.  Clouds came
in so further tests were not done, although it was not really 
clear to me what I was planning to do next.


MKIII COMMENT: Sun Apr 23 21:46:56 GMT 1995
Restored the corrector memory boards.


COMMENT: Sun Apr 23 21:47:21 GMT 1995
Activity report:
Nice prominences on west limb, got carried away with streak
investigation, forgot to note down their PA.

No coronal activity.


COMMENT: Sun Apr 23 21:48:36 GMT 1995
Tapes:  MKIII:  H01016
	DPMON:  P00337
	LOWL:   L00224

Sun Apr 23 21:50:10 GMT 1995: Filemark
SCAN-LOG 
SCAN-LOG  16:50:19.  4/23/95 DOY 113      
    17:04:51      17:08:02      17:11:15      17:14:26      17:17:40  
    17:20:50      17:24:01      17:27:10      17:30:22      17:33:32  
    17:36:44      17:39:56      17:43:09      17:46:21      17:49:34  
    17:52:45      17:56:02      18:14:47      18:17:58      18:27:26  
    18:30:37      18:33:53      18:37:04      18:40:16      18:43:26  
    1847 0 CL     18:50:54      1856 15CL     19:02:16      19:06:16  
    19:09:27      19:12:40      19:15:50      19:19:01      19:22:11  
    19:25:23      19:28:33      19:31:46      19:34:57      19:38:08  
    19:41:18      19:44:29      19:47:38      19:50:49      19:53:59  
    19:57:11      20:00:23      20:03:33      20:06:43      20:09:54  
    20:13:04      20:16:15      20:19:26      20:22:37      20:25:47  
    20:29:03      20:32:13      20:35:24      20:38:33      20:41:46  
    20:44:55      20:48:06      20:51:16      20:54:28      20:57:39  
    21:00:54  
  0 ERRORS
OK