W.J. Altenhoff. determined influences of the (sometimes
high)
offset-position
in azimut of receivers in the secondary focus to the pointing in
elevation
at high elevation. That can be corrected by an additive term 
Phorn
to the correction value in elevation. He also determined a systematic
pointing
difference, if the telescope has moved 360 degrees. That is assumed to
be influenced by the cable-twist in azimut, which can be corrected by
another
constant with an additive term Pcable to
the correction value in azimut. Therefore
these new
additive
terms to the pointing corrections have been built in the telescope
drive
program by J. Schraml. They are active since 7-nov-97.
For that reason the following constants are newly
introduced:
Haz:
Shift of horncenter in azimut (depending on receiver)
Hel: Shift
of horncenter in elevation (depending on receiver)
AZtw:
Constant eliminating the influence of the cable twist in azimut ( today
the value is +10 " per rotation of 360 degrees)
More information about the calculation in the drive
program one can
find in
