ALTANA LC 2 - Manual (Page 13)

If a button is pressed
constantly, the value is
automatically reduced or
increased.
A measurement range
between 0.900 and 1.100 is
possible. It corresponds
with a deviation of the
calibration liquid of ± 10 %
of the set value 1 M
.
(Thus a resolution of 0.5 %)
If none of the two buttons is
actuated for more than 5 s,
the set calibration factor is
saved together with the
instrument parameters. This
is confirmed by L5 in the
display.
This calibration procedure
requires some practice but
avoids unintentional
overwriting of the calibration
values.