Turret positions

feb, 2002

Turret position history:

Each receiver has a turret position to place the horn at the focus. The table below has the history of the turret positions for each receiver and what was used to determine the new position.

turret positions by date
sband xmt	62.29 14may04-> current 61.97 14feb04 -> 14may04 (02may04 survey) 62.16 29jan00-> 14feb04 survey 62.25 02jul99->29jan00 trk src using xmter 60.24 22may88->02jul99 . tx + interlock at 65.8 deg (measured 2jul99)
sbn rcv	76.90 14may04-> current 76.56 14feb04 -> 14may04 (02may04 survey) 76.83 29jan00-> 14feb04 survey 76.60 17dec98->29jan00 survey 75.00 start->17dec98
sband wide	104.03 14may04 -> current 103.66 14feb04 -> 14may04 (02may04 survey) 103.88 29jan00-> 14feb04 survey 103.80 start->29jan00 from single track pnting
sband high	125.94 14may04 -> current 125.55 14feb04 -> 14may04 (02may04 survey) 125.827 03apr02 (got survey sign offsets correct) -> 14feb04 survey 125.75 02apr02->02apr02 ignored survey, used position from turret swings 124.15 23mar02->02apr02 from survey 29mar02 125.00 22mar02->31mar02 moved toward bump in noise temp. 124.00 22mar02->23mar02 from bill genter
xband	310.06 14may04 -> current 309.72 14feb04 -> 14may04 (02may04 survey) 309.94 08jan04 -> 14feb04 horn survey at new position 161.50 02apr02 (survey 29mar02)-> 08jan04 (horn moved, tracked source) 162.34 06feb02->02apr02 survey 04feb02 (turOffset wasbackwards!!) 161.99 19dec01->06feb02 center turret at peak of noise
lbn	310.14 29jan00-> survey 309.12 start->29jan00
430	251.8
cband	206.77 14may04-> current 206.38 14feb04 -> 14may04 (02may04 survey) 206.65 24may98-> 14feb04 horn survey 205.25 start->24may98
cbh_1	165.01 14may04 -> current 164.67 13feb04 -> 14may04 (02may04 survey) 164.57 -> 13feb04 (13feb04 survey)
cbh_2	158.38 14may04 -> current 158.01 13feb04 -> 14may04 (02may04 survey) 158.45 -> 13feb04 (13 feb04 survey)
lbwide	285.79 15may04 -> current 285.42 14feb04 -> 15may04 (02may04 survey) 286.52 29jan00-> 14feb04 horn survey 285.50 01jul98->29jan00 horn survey 284.70 start->01jul98
alfa	26.64 14may04 -> current 26.27 29apr04 -> 14may04 (02may04 survey) 26.5 start->29apr04 till 28apr04 survey.
610	182.71 23jan04 ->current 183.16 16jan04 ->23jan04 updated model 330.55 -> 16jan04 (horn moved)

Pointing model offsets and the turret positions. (...top)

The pointing model contains an azimuth (great circle) and zenith angle offset. There is a separate set of offsets for each receiver to allow for a misalignment of the horn in az, za.The azimuth offsets interact with the turret position. If the turret position is wrong, then the az offset for that reciever can compensate for it. Tilts of the feed assembly can also affect the turret offset (as long as the tilt is not about the focal point). The tables below has the azimuth and zenith angle offsets used in the various models. It also contains the difference RcvrOffset- sbnOffset where sbn is the horn used to make the models. If the horns are placed correctly then rcvrOffset-sbnOffset should be zero.
Plot of the most recent (model15 may04) az/za offsets

model offsets [asecs] by rcvr. Includes rcvr-sbn offset difference
model/rcv/date	turpos	azOff	rcv-sbn azOff	zaOff	rcv-sbn zaOff	comment
		610
model14/	182.71	-42		30.78		feed move 14jan04 used calib runs
model15/	182.71	-45.35		-97.48		verify run after model 15
		sbn
mod9/sbn/may98	75.00	-46.73	0	-32.34	0
mod10/sbn/jan99	76.60	-40.99	0	-76.13	0
mod11/sbn/feb00	76.83	-41.66	0	-90.04	0	survey
mod12/sbn/feb01	76.83	-35.50	0	-92.34	0
mod13/sbn/jan02	76.83	-39.29	0	-98.35	0
mod14/sbn/mar03	76.83	-38.81	0	-79.26	0
mod14/feb04	76.56	-50.96		-79.26		survey feb04
mod15/may04	76.90	-40.		-102.55		survey may04, za not moved after survey (no room hole)
		lbn
mod9/lbn/may98	309.12	-11.18	35.55	-8.37	23.97
mod10/lbn/jan99	309.12	-80.66	-39.67	-50.08	26.05
mod11/lbn/feb00	310.14	-49.74	-8.08	-94.38	-4.34	survey
mod12/lbn/feb01	310.14	-41.66	-6.16	-99.76	-7.42
mod14/lbn/mar03	310.14	-16.41	-15.38	-90.48	-8.93
		lbw
mod9/lbw/may98	285.50	-11.18	35.55	-68.37	-36.03
mod10/lbw/jan99	285.50	-80.79	-39.80	-111.43	-35.30
mod11/lbw/feb00	286.52	-13.07	28.59	-91.92	-1.88	survey ** lbw turret offset
mod12/lbw/feb01	286.52	-06.91	28.59	-94.22	-1.88	computed backwards!!
mod14/lbw/mar03	286.52	-16.41	22.40	-90.4	-11.22	new rcvr no survey yet
mod14/feb04	285.42	-64.6		-90.48		survey feb04.
mod15/may04	285.79	-45.53		-116.21		horn move,survey,model may04 za not moved (no room hole)
		sbw
mod11/sbw/feb00	103.80	-42.66	-1.	-90.0	-.04	survey
mod14/sbw/mar03	103.88	-52.78	-13.97	-75.42	3.84
mod14/feb04	103.66	-62.68		-75.42		survey feb04
mod15/may04	104.03	-38.77		-89.56		horn move,survey,model may04
		sbh
mod13/sbh/apr02	125.827	-45.02	-5.73	-98.35	0.	survey 29mar02
mod14/sbh/mar03	125.827	-46.11	-7.30	-77.62	1.64
mod14/feb04	125.55	-48.71		-77.62		survey feb04
mod15/may04	125.94	-44.09		-86.12		horn move,survey,model may04
		cband
mod9/cb/may98	206.65	31.44	78.17	-22.34	10.
mod10/cb/jan99	206.65	-42.50	-1.51	-70.07	6.06
mod11/cb/feb00	206.65	-39.08	2.58	-94.28	-4.24	survey
mod12/cb/feb01	206.55	-31.14	4.36	-97.83	-5.49
mod14/cb/mar03	206.65	-47.83	-9.02	-79.78	-0.52
mod14/	206.38	-59.98		-79.78		survey 14feb04, modified offsets
mod15/may04	206.77	-42.45		-80.32		horn move,survey,model may04
		cbh_1
mod14/cbh	164.67	-63.41		-68.64		survey 14feb04. pnt offsets.calib feb04
mod15/cbh	165.01	-40.89		-87.14		horn move,survey,model may04
mod15/cbh,x102	165.01	-41.17		-90.96		updated offsets from x102 data(thru dec04)
		xband
mod13/xb/jan02	162.34	-00.53	-39.82	-96.75	1.6	survey (04feb02)
mod13/xb/apr02	161.50	-40.53	-1.24	-96.75	1.6	survey 29mar02 jan02turret offset was backwards
mod14/xb/mar03	161.50	-38.83	-0.02	-80.80	-1.54
mod14/feb04	309.72	-56.74		-78.11		horn move, survey feb04
mod15/may04	310.06	-38.97		-85.85		horn move,survey,model may04

Notes:

model15/may04 survey. After the may04 surveys, sbn and lbw were not moved in the x direction (za) because there was no room in the hole in the turret floor.

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