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20060825 report

CW and CCW inclinometry - both yield 'low-amplitude TY data


Inclinometry ws done as follows:

    Datasets  El Dirn     HST     mean leg temperatures   Humidity
                          start     start   middle   end       %
  ( 20060821  89  cw      00:29      8.0      7.4    7.0      -- 
    20060822  89  cw      18:00       -        -      -       -- 
    20060824  89 ccw      04:00      8.1      7.5    7.1      -- )
    20060825  89  cw      01:00      6.7      6.4    6.2      --
    20060825  89 ccw      04:00      6.2      6.1    6.0      --

The datafiles are given UT-derived names. Data is recorded from the 3 active inclinometers only: there is no strain gauge data, for instance.

The raw data from channels 1,4,7 (X-axes), 2,5,8 (Y-axes) and 3,6,9 (temperatures) are shown below for the CW run:

Click on image for better view

. . and for the CCW run:

Click on image for better view

The TY data are of the 'low-amplitude' variety seen in the CW run of yesterday rather than the normal variety seen in the CW run on the 23rd and previously - i.e. in and before January 2006:

It's actually not useful to describe these data as 'low-amplitude' : they do not even resemble the older data in profile, with more anti-correlation of features, if anything. The setting of the 'Filter' switches on the 'TMU' inclinometer in the receiver cabin was checked before these most recent runs.

Noise levels from CW/CCW turnaround
The CW & CCW data have been taken in one 6-hour long session. The az_file used contains several (8) requests for data at az=439.09, which is the last point of the CW sequence and the first of the CCW sequence. We can use the extra six data to estimate noise levels in each channel :

      Channel            1     2     3     4     5     6     7     8     9
       Axis             TX    TY    TT    LX    LY    LT    LX    LY    LT
   Noise (s.d. of 6)   0.7   3.4  0.05   0.4   2.7  0.05   0.7   1.2  0.05 mV

(Recall: 1mV = 0.05" for channels 1,2,4,5,7,8 and 1mV=0.1degC for channels 3,6,9)

Contact: Iain Coulson. Updated: Mon Aug 28 12:08:16 HST 2006

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