Another tracking experiment was performed with the s-curve correction effectively disabled (by setting SCURVE.AMP = 0):

• Elevation residuals
  There is no obvious sign of a jump in the elevation residuals through transit - even if there are +-2" systematics that I'd rather not see. For comparison with similar data taken with the s-curve correction active see here, where a 4" high, 'step'(!) seems fairly obvious between az=170 & 190.

  My conclusion (tho' I'd admit it's rather weak) is only that the scurve correction is not obviously helping to reduce the systematic erorrs. It's weak because the data are only barely different in the key characteristics, and because the expected magnitude of the correction being applied at this elevation is vanishingly small. More data probably needed to resolve this.

• Azimuth
  The azimuth residuals were expected to be free of errors introduced by the coding error detected last week ('sine instead of tan'), yet the 5" excursions seen here are exactly those seen on March 18, and seemingly corrected on April 18.

  It seems that the old version of the TCS was indeed used. (Curses !)

Transit Inlinometry
Data were taken with the antenna transitting at elevation=10^o :

These data also appear in the transit step archive. The 'step' at transit may be discerned as a 1.5" rise, but this is dwarfed by the instantaneous 4" glitches at az=179 and az=181, for instance. It may be that I didn't wait long enough to allow the TMU tiltable inclinometer to stabilize before taking these data; and a repeat may be useful. However, the current transit step size, (2.5", implying a value for SCURVE.AMP of -1.25") does not seem in urgent need of adjustment.