Experiment setup

• 430 dome receiver
• jpl horizon ephemeris file was used to track the moon.
  
• two 10 MHz bands. centered at 433 and 438 MHz
  
• mock spectrometers used in voltage sampling mode
• each 10 MHz band was sampled using:
• 8 bit i,q sampling.
• output was done using the pdev file format
• see pdev file format for the  output file format.
  

Observing  notes

05may14:

• he receiver was warm for this run. Tsys  was about 130 Kelvins.
• Start file: /share/pdata[1,2]/pdev/t2874.20140505.b[0,1]s1g0.00300.pdev
• there were 178 files for each band in this scan
• All times below are approximate.. except the start time is exact
  
• 16:11:13  (ast) start taking data (exact)
  
• 16:22:00  on the moon (about file 312)
• 16:44:xx       haystack radar on for awhile (very strong)
• 16:54:00    cal for 10 seconds (exact time)
• 17:34:05     start drifting off the moon
• 17:37          completely off the moon
• 17:38:xx      back on the moon
• 17:51           millstone radar back on with moon in a null of the beam (to reduce the ao signal)
• 18:17           tiepos 75 .. was tiepos 77 before
• 18:40          millstone hill was to come back on.
• 18:50:09      second scan started (file .00500)
• 19:07           off the moon
  
• 19:09           cal for 10 secs
• done..

06may14

• 17:01:37 started scan file .00000.
• 17:05:00  cal on 10 seconds
• 17:xx      datataking aborted. arun was copying file off of the datataking machine
• 17:08:24: start scan .00100.. this ran for the entire run
• 17:35:xx : millstone transmits
• 18:08:00  10 sec cal on moon
• 18:35:xx   millstone hill transmits
• 18:41:24  millstone radar off
• 18:52:00  stopped telescope tracking moon.. drift off.
• 18:55:xx   drive back onto moon.
• 19:05:20   millstone radar on  (not sure when they turned on)
• 19:11:xx   millstone radar off
• 19:46:18  hit max za.. moon moving out of beam
• 19:49:30   10 sec cal
• done...
  

Quick look at the spectra:  

• 2^24 points from the start of each file were processed for the first 50 files of scan 300.
• the 16 million points is about 1.6 seconds of data
• 8k fft's were done (1.2 Khz resolution), power computed and then averaged for the 1.6   seconds
• Each 1.6 sec spectra were normalized to their median value (Tsys).

• Both days:
• rfi in polA looks a lot stronger than that in polB
• rms's on moon were 30 to 40 counts for 1 sigma in the 8 bit digitizer.
• The cal temps are 95.5, 102.6 for polA, polB
• On the oscilloscope we saw rfi with 12 second periods reflected off the moon.
• land base radars (in PR) have 12 second rotation period.
• I've seen ship based radars with 4 second rotation periods.
  
• 05may14:
• moon come into beam during the 12th file : .00011.pdev
• Tsys was about 130 K off the moon.
  
• 06may14
• Tsys was about 80 K off the moon.
  
• file 121, 431.8MHz birdies starts drifting to higher frequency.
• at file 149 it has moved about 1 MHz.
• This may be rfi from the sbn postamp chassis. in the 327 receiver we saw it drift by this amount (more info)
  
• The rfi off the moon looks much stronger in polA than polB (pols are circular).
  
• this may be real or just a difference in Tsys for the 2 pols (when the dewar is warm.. need to check the cals).

Telescope position.

Processing:

• model correction was removed from the az,za encoder values
• the az,za was backcomputed to ra,dec of date.

• Page 1: 05may14:
• Top: RA (of date) vs hour of day (UTC)
• black AO telescope
• red moon ephemeris file
• 2nd: DEC(of date) vs hour of day (UTC)
• black AO telescope
• red moon ephemeris file
• bottom: position error Asecond (great circle)
• Black RaEphm - RaTelescope
• the error was computed as: (radif)*15*3600*cos(declination)
  
• red : decEphm  - DecTel
• The error was computed at: (decDif)*3600
• at 21.6 the telescope tracking was stopped so the moon drifted out of the beam
• . a few minutes later we drove back onto the moon.
• Page 2: 06may14 run.
• at 22.9 the telescope tracking was stopped so the moon drifted out of the beam
• . a few minutes later we drove back onto the moon.

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