Optics

june 2002

     Optics includes the surveys and adjustments to the reflectors as well as the pitch, roll, and focus measurements.

TOPICS:

Historical events for the optics.
MISC:
Surveying the primary reflector
Surveying the dome position from AO9
Tilt sensor measurements.
Surveying the tertiary
Surveying the horn positions.
Pitch, roll, and focus using theodolite and tilt sensors to compute the tiedown correction.
Field of view measurements.
Platform height, position, temp, tiedown Position, and tensions.
Cable measurements
Standing waves
Computations
MISC
See also: platform motions.
 


Historical events for the optics:


Surveying the primary reflector (top)

    I've tried to put together a timeline with names so that i can reference different data sets below. The dates are only approximate. A lot of the adjusting overlapped with the previous measuring.

Measuring only the tiedown cables (2000 targets)

Measuring/adjusting all 38000 targets.

Primary reflector surface errors measured jan01 after first re-alignment (M_TD1)
Primary reflector surface errors measured mar01 after 2nd re-alignment (M_TD2)
Primary reflector surface errors (east half). Photos taken oct,nov 2001 (M_SUR2).
Scatter plot of radial errors survey1 vs survey2 (pdf file) (M_SUR1,M_SUR2).
Survey2 results (and a comparison with survey 1)


Surveying the dome position from AO9  (top)

09aug01: Theodolite survey from AO9 of dome position versus az,za (With AO9 as origin)
09aug01: Theodolite survey from AO9 of dome position versus az,za (With reflector as origin)
feb03 : theodolite survey from ao9 of dome position before and after shimming.
jul03: theodolite survey from ao9.


Surveying the horn positions.  (top)

Horn position surveys.
The latest model offsets in az and za.
Finding the best turret position by tracking sources.


Pitch, roll, and focus using theodolite and tilt sensors to compute the tiedown correction.  (top)

aug01     : The pitch/roll of the telescope versus az,za (using the theodolite and tilt sensors).
aug01     : The pitch/roll of the telescope versus az,za (using the theodolite and tilt sensors..Reflector origin).
aug01: tiedown positions to correct for pitch, roll, and focus (reflector at origin).
jan02: Correlate pitch, roll with coma (cband).
feb02: simulate tiedown motion after shimming (reflector at origin).
feb02: shimming the elevation rails (reflector at origin).


Field of view measurements.  (top)

10jun02: Losses caused by offsetting the horn 19 and 25 cm using lbn and the turret.


Platform height, position, tiedown Position, and tension. (top)

year 2002:Tiedown tensions vs:platform height,temperature, and tiedown Position. Data and fits
year 2002:Td inches/platform inch, TdPos vs temp at platform focus position.
dec03: platform corner height vs za when looking at tower.
jan10: dynamic load on tiedowns from platform motion.
22feb10: fit tiedown tensions using 2008,2009 data.
17mar10: dome za that balances az arm when ch at stow.
18oct10: tdKips per platform motion if 1 inch
09apr15: measuring the average platform height with only 3 distomats.


Cable measurements:  (top)

mar06: td cable tensions and az,za positions when main cable catenary sag meaurments made.
jun16:  td cable tensions and az,za positions during the jun16 catenary survey.


Standing waves:  (top)

jan05: standing waves measured by moving the platform with the tiedowns.


Computations  (top)

Aoant simulation of 10ghz focus position with 869.781 foot radius
Phase delay along line feed needed for focusing.


MISC.  (top)

Horizontal offset of platform relative to AO9 monument.
Correlation of  the coma parameter and the pitch,roll, focus error (sband narrow).
kildal horn paper (includes phase center computation)
Tsys versus turret position for various receivers.
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