Plots
26,27Mar07 before the painting (.ps) (.pdf)
30mar07 pointing checks (.ps) (.pdf)
31mar07 pointing checks (.ps) (.pdf)
01apr07 pointing checks (.ps) (.pdf)
02apr07 pointing checks (.ps) (.pdf)
04apr07 pointing checks (.ps) (.pdf)
05/06apr07 pointing checks (.ps) (.pdf):
07apr07 pointing checks (.ps) (.pdf)
09apr07 pointing checks (.ps) (.pdf)
10apr07 pointing checks (.ps) (.pdf)
11apr07 pointing checks (.ps) (.pdf)
12apr07 pointing checks (.ps) (.pdf)
13apr07 pointing checks (.ps) (.pdf)
17apr07 pointing checks (.ps) (.pdf)
18apr07 pointing checks (.ps) (.pdf)
19apr07 pointing checks (.ps) (.pdf)
20apr07 pointing checks (.ps) (.pdf)
21apr07 pointing checks (.ps) (.pdf)
23apr07 pointing checks (.ps) (.pdf)
24apr07 pointing checks (.ps) (.pdf)

Intro  top

Dates   top

• 29mar07: installed cables t8 corner. Raised about 900 lbs
• 30mar07: rain.. not much work.
• 31mar07:
• installed cables t12,T4 corners.
• removed laser shack (about 2700 lbs from corner 4).
• 01apr07: about 500 lbs lifted to platform. standoffs for t12 corner
• 02apr07: half the lead from corner 4 removed?
• 03apr07: rest of lead removed from corner 4.
• 6900 lbs of lead was removed from corner 4 + 500 misc lbs.
• Total removed from corner 4 is: 2700(laser shack) + 6900 lbs (lead) + 500 lbs (misc) = 10100 lbs.
• 04apr07:
• about half the lead from corner 12 removed.
• Tilt sensor az spins done then tiedowns were readjusted to compensate for tilt (around 17:30).
• The tiedown reference was changed from:
• [14.8751 14.6161 13.2431] to
• [14.6808 15.4018 12.6517 ] prior to taking the pointing data.
  
• X102 data data taken starting around 17:30
• dome disable cable broken around 19:00.
• both azimuth encoders reset (after x102 data taken)
• 05apr07: working on az encoders. took  x102 data in the evening.
• 06apr07:Good Friday. No work on platform.
• Took x102 data
• After x102 data, computed az*sin(za) pointing error and updated pointing model to correct for az encoder offsets (caused by repositioning after the reset)
• 07apr07:
• Rest of lead corner 12 removed 9000+ lbs in total removed.
• Az swings done with tilt sensors. Fit for 1az term and then updated tiedown default positions to remove the tilt.\
• The new tiedown reference is: [14.9277,15.4312 12.3754]
• 31mar-07apr: Weight summary:
  • 3300 lbs steel outriggers cables raised + 600 lbs wooden blocks.
  • 18932 lbs removed: laser shack,sband power supply calbe splice tank and dielectric oil, lead.
• 08apr07:
• 09apr07:
  • raised 9 brackets 150 lbs each. Placed in corners 8 and 12.
  • checked lbw pointing after installation
• 17apr07: alfa lower from dome to electronics lab for maintenance.
• 18apr07: netting on bottom chord of each corner of triangle installed.
• 19apr07: Vertical netting installed corner 12.
• 20apr07: Vertical netting installed corner 8.
• 21apr07: Vertical netting installed 1 side corner 4. distomat 3 not working.
• 22apr07: Distomat 3 now working. The vertical tarp had been covering it.
• 23apr07: Floor on T12 corner.. (full of water). 2 sides corner 4
• 24apr07: Floor on corners full of water
  
• 25apr07:Stopped observing. Painting shutdown has started. All 3 corners have the 3 sides of the tarps up. No roof yet.
  

The Measurements:  top

• Page 1: pointing errors
• Page 1:  gain,Tsys,Sefd,Beamwidths.

30mar07 pointing checks (.ps) (.pdf): top

Data taken with sbn from 18 to 20 hrs AST.

The plots show the 30mar07 data plotted with a srcname suffix of  _m30.

The 26mar07 data is also plotted with a  srcname suffix of _m26.

Page 1: pointing errors fro 30mar07.

Page 2: pointing errors for 26,27,30 mar07 overplotted.

I don't see any obvious changes in the pointing. The drift to positive errors around az=80 was there previously (but it had been centered closer to azerr=0).

Page 2:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070330/chkpnt.pro

Data taken with sbn from 17 to 18  hrs AST. The laser shack had been removed earlier in the day.

The plots show the 31mar07 data plotted with a srcname suffix of  _m31.

The 30 and 26mar07 data is plotted with suffixes of _m30 and _m26.

Page 1: the pointing errors for 31mar07 by themselves.

Page 2: Cumulative pointing errors since 26mar07.  The source B0534+342 was tracked on 31mar07 and on 26mar07. The za errors have moved up a few arc seconds from the 26mar07 data. The az errors are consistent with the big dip around 160 degrees.

Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070331/chkpnt.pro

Data taken with sbn from 16 to 18  hrs AST. About 500 lbs of metal had been lifted today.

The plots show the 01apr07 data plotted with a srcname suffix of  _a01.

The 21,30 and 26mar07 data is plotted with suffixes of _m31,_m30, and _m26.

Page 1: the pointing errors for 01apr07 by themselves.

Page 2: Cumulative pointing errors since 26mar07.  The source B0618+145 was tracked on 01apr,26mar, and 30mar. There is a definite shift of the za errors around az=-80. This is probably the 1az term from the platform tilt.

Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070401/chkpnt.pro

Data taken with sbn from 16 to 19  hrs AST. Half the lead from corner 4 was removed earlier today (800 lbs?)

The plots show the 02apr07 data plotted with a srcname suffix of  _a02.

Page 1: the pointing errors for 02apr07 by themselves. You can clearly see the 1 azimuth term in the za errors. It is peaking at az=120 deg (corner 4). The az errors peak 90 degrees away (around 210 deg) The amplitude is aound 20 arcseconds.

Page 2: Cumulative pointing errors since 26mar07.  The data is starting to get mixed up since each day something caused a change in the pointing.

Page 3:  gain,Tsys,Sefd,Beamwidths. Looks like the flux for 0453+227 is a little low at 2380Mhz.

processing: x101/070402/chkpnt.pro

Data taken with sbn from 17:30 to 19  hrs AST. All the lead from corner 4 and half the lead from corner 12 was removed. Az spins were done with the tilt sensors from 16:30 to 17:30. The 1 azimuth term was fit to the data and the tiedown reference positions were moved from [14.165,13.905,12.522] to [13.9707,14.6907,11.9306] [td12,4,8]. The major difference was the extra pulldown on td4 (13.905 to 14.691) to compensate for the 10000 lbs removed from corner 4.

The plots show the 04apr07 data plotted with a srcname suffix of  _a04.

Page 1: the pointing errors for 04apr07 by themselves. The 1 az term is no longer as prominent as 02apr07.

Page 2: Cumulative pointing errors since 26mar07.

Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070404/chkpnt.pro

• Data was taken on 05apr07 16:30 to 21:30 and on 06apr07 from 16:30 to 18:00 using sbn. This data was taken after the azimuth encoders were repositioned and reset on 05apr07 .
• Page 1. The pointing errors for 05,06apr07. The 3rd plot "az errors vs za" shows the az encoder offset. The plots are in great circle arc seconds. An az encoder offset would show up az an azEncErr*sin(za). Two of the sources show the ramp in za. B0518+165 doesn't. This may be because it does not cover a very large azimuth range and the za slope is being offset by a 1az or 3 az term.
• Page 2:
• The top plot shows azErr versus za (on the sky).
• The bottom plot is azErr*sin(za). This is the az encoder offset. The average value for the 3 sources is -35.9 arc seconds (at the encoder).
• A -35.9 Asecs encoder error at the 60 foot radius is a positioning error of -.123 inches. You need to subtract this value to get the correct encoder value. The pointer should have been positioned +.123 inches (clockwise) from where it was (on the scribe mark).  We centered the index on the scribe mark. As I recall,  the previous positioning of the encoder index was to the right of the mark (back in november). That was when the pointing model azerr*sin(za) was computed. We also had the dome at 8 degrees za when we did this. It may have been at za=10 the last time the index was set.
• The pointing models were updated. The az*sin(za) term was incremented by +35.9 asecs.
• Page 3: pointing errors for data taken in apr04
• Page 4: gain,tsys,sefd, beamwidth for data taking in apr04.
processing: x101/070406/chkpnt.pro

• The rest of the lead from corner 12 was removed earlier in the day. The total removed was about 9600 lbs.
• 16:45 to 17:15 azimuth swings done with tilt sensors to measure the platform tilt. The tiedown positions were then updated to remove the tilt. he tiedown reference position are now:
• [td12      , td4        ,td8]
• [14.6807,15.4107,12.6516] tdRef set 04apr07 after td4 weight removed.
• [14.9276,15.4311,12.3753] tdRef set 07apr07 after td12 weight removed.
• There is now a 3 inch difference in the stroke of td8 and td4
• Data taken with sbn from 17:30 to 21:30  hrs AST. 
• The plots show the 07apr07 data plotted with a srcname suffix of  _a07.
• Page 1: the pointing errors for 07apr07 by themselves. The az errors versus za are now drifting up to about +10 asecs. It may be that the -35.9 encoder offset put in 06apr07 was not necessary.
• Page 2: Cumulative pointing errors since 01apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070407/chkpnt.pro

• Data taken with lbw from 16:30 to 20:00  hrs AST. This was to check the pointing with lbw after it had been reinstalled in the dome o the pprevious week. 
• The plots show the 09apr07 lbw data plotted with a srcname suffix of  _a09.
• Page 1: the pointing errors lbw from 09apr07 . The errors look similar to the sbn errors of the previous days.
• Page 2:  gain,Tsys,Sefd,Beamwidths for the lbw data.

processing: x101/070409/chkpnt.pro

• Data taken with sbn from 16:00 to 19:00  hrs AST. 
• The plots show the 10apr07 data plotted with a srcname suffix of  _a10.
• Page 1: the pointing errors for 10apr07 by themselves. It rained while this data was taken but the distomats/tiedowns continued to run. The one or two outliers may be because of the rain.
• Page 2: Cumulative pointing errors since 02apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070410/chkpnt.pro

• Data taken with sbn from 16:30 to 21:30  hrs AST. 
• The plots show the 11apr07 data plotted with a srcname suffix of  _a11.
• Page 1: the pointing errors for 11apr07 by themselves.
• Page 2: Cumulative pointing errors since 05apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths. The red -- and black triangles are the 09apr07 lbw data.

processing: x101/070411/chkpnt.pro

• Data taken with sbn from 18:00 to 18:46  hrs AST. The time was shortened because of an oil leak in azimuth motor 82 transmission that had to be repaired prior to observing.
• The plots show the 12apr07 data plotted with a srcname suffix of  _a12.
• Page 1: the pointing errors for 12apr07 by themselves.
• Page 2: Cumulative pointing errors since 06apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths. The offset Tsys,sefd data is from the 09apr07 lbw data.

processing: x101/070412/chkpnt.pro

• Data taken with sbn from 16:00 to 19:00  hrs AST.
• The plots show the 13apr07 data plotted with a srcname suffix of  _a13.
• Page 1: the pointing errors for 13apr07 by themselves.
• Page 2: Cumulative pointing errors since 07apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths. The offset Tsys,sefd data is from the 09apr07 lbw data.

processing: x101/070413/chkpnt.pro

• Data taken with sbn from 16:00 to 20:45  hrs AST. Alfa was removed earlier in the day. There was rain during the observations but the distomats continued running.
• The plots show the 17apr07 data plotted with a srcname suffix of  _a17.
• Page 1: the pointing errors for 17apr07 by themselves. Removing alfa did not make a large change in the pointing.
• Page 2: Cumulative pointing errors since 09apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths. The offset Tsys,sefd data is from the 09apr07 lbw data.

processing: x101/070417/chkpnt.pro

• Data taken with sbn from 16:00 to 20:45  hrs AST. There was overcast/drizzle during the observations but the distomats continued running.
• The plots show the 18apr07 data plotted with a srcname suffix of  _a18.
• Page 1: the pointing errors for 18apr07 by themselves.
• Page 2: Cumulative pointing errors since 10apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070418/chkpnt.pro

• Data taken with sbn from 16:00 to 19:00  hrs AST.
• The plots show the 19apr07 data plotted with a srcname suffix of  _a19.
• Page 1: the pointing errors for 19apr07 by themselves.
• Page 2: Cumulative pointing errors since 11apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070419/chkpnt.pro

• Data taken with sbn from 18:24 to 19:00  hrs AST. There had be a power outage earlier in the day. Most of the observing time was lost.
• The plots show the 20apr07 data plotted with a srcname suffix of  _a20.
• Page 1: the pointing errors for 20apr07 by themselves.
• Page 2: Cumulative pointing errors since 12apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070420/chkpnt.pro

• Data taken with sbn from 16:00 to 18:00  hrs AST. Distomat 3 was not working. Looks like that covered or bumped the retroreflector when they covered that side today.
• The plots show the 21apr07 data plotted with a srcname suffix of  _a21.
• Page 1: the pointing errors for 21apr07 by themselves.
• Page 2: Cumulative pointing errors since 13apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070421/chkpnt.pro

• Data taken with sbn from 16:00 to 19:00  hrs AST. Heavy rain, distomats not working. Flooring in corners of platform full of water.
• The plots show the 23apr07 data plotted with a srcname suffix of  _a23.
• Page 1: the pointing errors for 23apr07 by themselves. Both the az and za errors have larger than normal negative offsets. This is either from the tiedowns not working (rain) or the water in the floor of corner 12 and 8 tilting the platform.
• Page 2: Cumulative pointing errors since 17apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070423/chkpnt.pro

• Data taken with sbn from 13:45 to 19:00  hrs AST. Rain with distomats not working.
• The plots show the 24apr07 data plotted with a srcname suffix of  _a24. This is the last day of observing.
• Page 1: the pointing errors for 24apr07 by themselves.
• Page 2: Cumulative pointing errors since 17apr07.
• Page 3:  gain,Tsys,Sefd,Beamwidths.

processing: x101/070424/chkpnt.pro

---

Tilt sensor measurements top

• 27mar07 az swings:
• 31mar07 az swings:
• The 1az term has increased from about .006 to .010 after the laser shack was removed.
• 04apr07 az swings:
• The lead had been removed from corner 4 and some from 12. Az swings were done, the tiedowns were moved, and then another set of az swings were done.
  
• The original tiedown reference position was: [14.8751 14.6161 13.2431]
  
• The new tiedown reference position is : [14.6808 15.4018 12.6517 ]
• Tiedown 4 is pulling more because of the lead removed from corner 4.
  
• 07apr07 az swings, updated tiedown positions.
• The tiedowns were returned to the 27mar07 reference position and then two az swings were done with the tilt sensors. The 1 az term was fit and then the tiedowns were moved to give the same platform tilt as 27mar07.
• The new tiedown reference position is: [14.9277,15.4312 12.3754]

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