Testing lbw_gain and balancing

Goals

  • Repeat lbw_gain and balancing tests that got screwed up by VEGAS faults

Details

  • Start at 8:00am - configure for KFPA. Boom may be extended at some point
  • 8:15am - configure VEGAS for Mode 6, KFPA, -20dBm
  • Not every bank has balanced properly; use Bank F, pol B looks good

   lbw_gain              measpwr2    filter_snap
2**25     33554432         -20.1            -43
2**26     67108864          -20               -43
2**27    134217728          -20              -39
2**27.5  189812531        -20               -36
2**28     268435456        -20               -33
2**29     536870912        -20               -27.5
2**30     1073741824      -20               -21.5
2**30.5  1518500249      -20               -18.5
2**31     2147483648       -20              -15.5
2**31.5  3037000499       -20              -12.5  (just starting to clip)
2**32-1   4294967295     -20               -8.0
2**31.5   3037000499     -20               -12.5
2**31      2147483648     -20               -15.5
2**30.5   1518500249    -20               -18.5
2**30       1073741824   -20                -21.5
2**29      536870912       -20               -27.5
2**28      268435456       -20               -33
2**27.5   189812531       -20                -36
2**27.0   134217728        -20                -39
2**26.5     94906265       -20                -41
2**26        67108864       -20                -43

Mode 6, -17dB input level (as high as I can go), Bank F Mechanics start messing with PF boom... Need to watch out for this.
2**25     33554432       -17     -45
2**26     67108864       -17     -41
2**27    134217728       -17     -36
2**27.5  189812531      -17    -33
2**28     268435456      -17    -30
2**29     536870912      -17    -24.5
-- boom is extending here... then retracted again.
2**30     1073741824    -17    -18.5
2**30.5  1518500249    -17    -15.5
2**31     2147483648     -17    -12.5
2**31.5  3037000499     -17    -8.5  (just clipped)
2**32-1   4294967295     -17   -3.5  (definitely clipped)  
2**31.5   3037000499    -17    -8.5
2**31      2147483648     
2**30.5   1518500249    -17   -15.5
2**30       1073741824  
2**29      536870912        -17   -24.5
2**28      268435456      
2**27.5   189812531         -17   -33
2**27.0   134217728       
2**26.5     94906265        -17   -38.5
2**26        67108864      

Switch to mode 20, an L8 mode. Bank A, pol 2 (red) looks good.

lbw_gain        measpwr        sb1snap  
2**7     128           -19.5              -46
2**8     256           -19.5              -41
2**9     512          -19.5               -36
2**10   1024       -19.5               -30
2**11    2048        -19.5              -25
2**12    4096        -19.5              -19
2**13   8192         -19.5              -13
2**14   16384        -19.5             -3    heavily clipped
2**15   32768        -19.5              0.75 (totally clipped)
2**14.5 23170       -19.5              0.5
2**14    16384        -19.5             -3
2**13.5  11585      -19.5              -8
2**13      8192      -19.5              -13
2**12.5   5792       -19.5             -16
2**12      4096       -19.5             -19
2**11.5  2896        -19.5            -22
2**11     2048        -19.5            -25
2**10.5   1448        -19.5           -28
2**10      1024        -19.5           -31
2**9        512         -19.5             -36
2**8        256          -19.5            -41
2**7.5     181          -19.5            -43
2**7        128          -19.5            -45
2**6         64           -19.5            -46

Finally have a consistent set of numbers - stop here!

Topic revision: r2 - 2015-01-27, RichardPrestage
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