Further Left- + Spare- Inclinometry

The first inclinometry data of the new year, and the first since those reported on 981215 , are described and analysed below :

   Datasets          HST start      mean leg temperatures   Humidity
                                    start   middle   end       %
 ( inc981213           10:17         2.4     3.5     4.4      12 )
   inc990104a          14:15         1.0     1.7     2.0      70
   inc990104b          21:50         0.0    -0.3    -0.4      95

As before, the S-pare inclinometer is positioned on the L-eft A-frame, slightly forwards of the conventional 'Left' inclinometer, and is plugged into data Channels 7,8,9, usually used for the R-ight A-frame inclinometer.

The differences between these new data and the previous set and between the two new datasets were displayed and examined, and it was clear that inc990104a.dat suffered some sort of settling problem, the exact nature of which is under investigation. The only useful differences to be discussed further are shown below (20mV = 1") :

Apart from a drift in baseline or change in zero-point, LX, SX, LY and SY change between these two dates by less than 0.5", 0.5", 1.0" and 1.0", respectively; i.e. no large spikes have occurred.

L-R symmetry
The inc990104b data are used to update the symmetry measures using TY as a reference, as was started on 981115 :

Conclusions
The L-eft inclinometer continues to paint a more pessimistic picture of the correlation between left and right (or TMU) than does the spare, but apparently the antenna structure is currently very symmetric !