----------------------------------------------------------------------------- Mauna Loa Solar Observatory Observer's Log ----------------------------------------------------------------------------- Fri Apr 21 16:41:56 GMT 2006 Year: 06 Doy: 111 Observer: yasukawa WEATHER COMMENT: Fri Apr 21 16:42:00 GMT 2006 In extensive, thick cirrostratus overcast, S wind 5 mph, temp 35 F. ___end___ **pics_PROCESSING PROBLEM**: Fri Apr 21 17:19:00 GMT 2006 Network connection went down briefly only on keiki and kenobi. Mssrestore got disrupted. Restarted mssrestore once network connection came back up. ___end___ WEATHER COMMENT: Fri Apr 21 17:55:11 GMT 2006 Cirrostratus thinning, opened domes. ___end___ COMMENT: Fri Apr 21 17:55:36 GMT 2006 Guider left on overnight. ___end___ Fri Apr 21 17:57:53 GMT 2006 CHIP Start Patrol Fri Apr 21 17:58:58 GMT 2006 PICS Start Patrol WEATHER COMMENT: Fri Apr 21 17:59:35 GMT 2006 Started up but patch of thick stuff moved over again, guiding may be iffy. ___end___ Fri Apr 21 18:00:16 GMT 2006 PICS Flat Fri Apr 21 18:01:51 GMT 2006 CHIP LSD Fri Apr 21 18:02:27 GMT 2006 PICS End Flat Fri Apr 21 18:02:32 GMT 2006 PICS ReStart Patrol Fri Apr 21 18:03:33 GMT 2006 CHIP End LSD Fri Apr 21 18:03:39 GMT 2006 CHIP BiasLSD Fri Apr 21 18:04:18 GMT 2006 CHIP End BiasLSD Fri Apr 21 18:04:24 GMT 2006 CHIP Bias Fri Apr 21 18:05:04 GMT 2006 CHIP End Bias Fri Apr 21 18:05:09 GMT 2006 CHIP ReStart Patrol PSPT COMMENT: Fri Apr 21 18:08:25 GMT 2006 Observing. ___end___ **MLSO PROBLEM**: Fri Apr 21 18:10:03 GMT 2006 Declination appears to be drifting. Signal on guider monitor is dropping down from usual middle position. PICS image, though, remains centered and stable at this time. ___end___ **MLSO PROBLEM**: Fri Apr 21 18:24:04 GMT 2006 Hoike images indicating declination drift. ___end___ **PSPT PROBLEM**: Fri Apr 21 18:28:55 GMT 2006 PSPT crashed at 1817 UT. K/r ___end___ **MLSO PROBLEM**: Fri Apr 21 18:31:08 GMT 2006 Guider monitor o'scope dot slowly moving back to nominal position. Guider still not pointing well but that also could be due to the very thick clouds I'm in at this time. ___end___ Fri Apr 21 18:55:48 GMT 2006 CHIP End Patrol WEATHER COMMENT: Fri Apr 21 18:55:58 GMT 2006 Stopping due to thick overcast. ___end___ Fri Apr 21 18:56:10 GMT 2006 PICS End Patrol Fri Apr 21 20:41:40 GMT 2006 CHIP Start Patrol Fri Apr 21 20:41:51 GMT 2006 PICS Start Patrol **MLSO PROBLEM**: Fri Apr 21 20:35:52 GMT 2006 In September 1991, the gearing in the declination Vernitron motor failed, producing a similar lazy-to-no response in the guiding declination. At that time the motor was replaced with a spare and the old motor was sent back to Boulder for repair. This motor problem occurred again in May 1995 and in January 2001. There is a good tip on removing the motor in the 01d022 observer log. A refurbished motor is currently in the spares inventory. I also wired up an interconnect to make the motor replacement less contortional. Opened spar and checked gearing between motor assembly and dec drive worm gear. Gears feel OK, albeit a bit tight. Removed motor and checked it. The motor also appears OK, spinning without resistance with no load. Reassembled dec drive mechanism and took some photos of it and the PICS C1 assembly while it was exposed for photo-documentation effort. ___end___ **MLSO PROBLEM**: Fri Apr 21 20:49:04 GMT 2006 Although sun is still behind moderate to thick cirrostratus and altocumulus, the guiding still appears to drift -- based on o'scope trace. ___end___ **MLSO PROBLEM**: Fri Apr 21 20:58:29 GMT 2006 Declination worm screw was closer to one limit than the other. Tried pushing spar in opposite direction and reset the guider and dec to see if I could drive dec closer to center and see if it behaves any better over there. Declination did not drive spar toward centering screw nor the image over the occulter. It looks like the electronics may not be providing any drive voltage to the dec motor and the drift we are seeing is just static drift of the sun's path relative to the static dec position of the spar. ___end___ WEATHER COMMENT: Fri Apr 21 21:32:28 GMT 2006 In thick orographic clouds. ___end___ Fri Apr 21 21:32:48 GMT 2006 CHIP End Patrol Fri Apr 21 21:33:16 GMT 2006 PICS End Patrol **MLSO PROBLEM**: Fri Apr 21 23:52:12 GMT 2006 Checked guider motor voltages at MS connector on spar. 115 VAC is OK. When dec is reset, pins C to D is 26 VAC. When limit switch is pressed, C to D goes to 36 VAC (should be 39 VAC). When center switch is pressed, C to D goes to 0 VAC (dec relay is released). When dec is reset again, C to D goes to 26 VAC. Voltages to motor/tach appear to behave properly except that the recenter voltage is a bit low. ___end___ WEATHER COMMENT: Sat Apr 22 00:08:13 GMT 2006 In fog, closing domes. ___end___ **MLSO PROBLEM**: Sat Apr 22 01:17:17 GMT 2006 Revisited the motor and gear train. Softened up the worm gear grease a bit with a shot of WD-40. (could not find the grease gun) No change in problem. Checked motor operation under no load with declination power on and it appeared to run OK at the different voltages (run and recenter). I could stop the output gear with my finger at either voltage. Checking it against the spare motor/tach in the cabinet, both motors behaved similarly so I installed the spare. The spare would not run the declination gear train. I could feel it vibrating (running internally). A quick shot of WD-40 on the bearings of the gearbox between the motor/tach and the worm gear box did the trick, the motor started turning the gear train and the declination system began moving as it should. Tested the limit switch behavior and the dec recentered itself and turned itself off. Think it is working now. We will have to check the bearings in the intermediate gearbox for wear and the overall lubrication, regreasing the worm drive with some real, fresh grease sometime soon. ___end___ NICE CHIP IMAGE: 1814 NICE PICSLIMB IMAGE: 1824 NICE PICSDISC IMAGE: 1814 WEATHER COMMENT: Sat Apr 22 01:45:49 GMT 2006 Still in thick overcast. ___end___ COMMENT: Sat Apr 22 02:17:09 GMT 2006 10 man-hours on site. ___end___ Sat Apr 22 02:17:48 GMT 2006 MkIV