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TPTCSPNT_070924 

*UT*   *scan*
       Observe source near NCP and run pointing scans at normal rate vs. slow rate 
       Scheduling block = Point0750slow  (regular peak scan, followed by 8 arcmin per minute
01:37  Use 0750+8241 near its lower culmination (elevation rate very small), T_antenna = 1K
01:38   *Scans*   *Rate8           *Azimuth*       *delta8       *Elevation*    *delta*
                               forward  backw  (mas)  avg LPC   forward  backw  (mas) avg LPC    LFC
       1316-1320  normal (fast)  0.015   0.049 +34   -0.013     0.061    0.044  -17   0.005     0.108
01:42  1321-1324  slow           0.008   0.010  +2   -0.004    -0.025   +0.031  +56   0.008  
       Use 0017+8315 (azimuth rate very small, about 0.001deg/sec = 3.6arcsec/sec), T_antenna = 2K
01:48  1325-1329  normal (fast)  0.010   0.007  -3   +0.004     0.062   0.058    -4   0.068     0.404 
       1330-1333  slow (8'/min)  0.019   0.020  +1   +0.023     0.012  -0.007   -19   0.070      
       1334-1337 med (8'/30sec) -0.017  -0.016  +1   +0.007    -0.021  -0.015    +6    
02:04  1338-1342  normal         0.028   0.012 -16   +0.027     0.001   0.025   +24   0.065    0.558
       1343-1346  slow          -0.004  +0.009 +13   +0.030    -0.017  -0.013    +4   0.050
       1347-1350 medium         -0.001  -0.008  -7   +0.025    +0.000  +0.015   +15   0.058
       Go back to 0750+8241 with the 3-speed version of the scheduling block
02:18  1351-1355 normal         -0.014  -0.016  -2   +0.010    -0.036  -0.030    +6   0.025    0.477
       1356-1359 medium         +0.013  -0.026 -39   +0.004    -0.025  +0.011   +36   0.018    
       1360-1363 medium         +0.047  -0.012 -59   +0.022    +0.027  -0.007   -34   0.028
Oscillations in receiver power seen whenever going through the source at medium rates:  probably servo oscillations.
Change strategy: scan further when going at higher rates, to try to avoid servo oscillation when passing through the peak
02:34  1364-1368 norm 20'/30sec +0.017  -0.007 -24   +0.027    +0.037  +0.027   -10  +0.060   -0.656
       1369-1372 8'/60sec       +0.000  +0.004  +4   +0.028    -0.029  -0.021    +8  +0.035
       1373-1376 9.6'/60sec     +0.005  +0.003  -2   +0.033    +0.086  +0.014   -72  +0.085
       1377-1380 12'/60sec      -0.010  -0.021 -11   +0.017    -0.025  -0.007   +18  +0.069
02:53  1381-1384 16'/60sec      -0.011  -0.004  +7   +0.010    -0.010  -0.002    +8  +0.062 
       1385-1388 24'/60sec      +0.024  +0.014 -10   +0.029    -0.007  +0.016   +23  +0.067
End this experiment, and run test of DaisyAtHalfPower
For some reason, the session got incremented to 70925

-- Main.ToddHunter - 24 Sep 2007

Attachment: sort Action: Size: Date: Who: Comment:
DaisyHalfPower2.gif action 21641 24 Sep 2007 - 03:45 ToddHunter Xband daisyscans: center, halfpoweraz, halfpowerel

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Revision r1.5 - 28 Nov 2007 - 23:31 GMT - ToddHunter
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