Ten-Haaft Oyster Vision II Operating Instructions Manual page 16

The lower the elevation of the satellite in the sky, the lower the reception
head (LNB) will move over your roof during the satellite search. If there
are any roof attachments within the range of rotation, this could lead to a
collision and thus to the damage of your Oyster Vision or to the parts
concerned. Often, however, the system must be installed with limited
available space. The setting of Min. elevation prevents that the LNB
lowers itself below a certain value. The larger the entered number, the
higher is the lower limit for the LNB. If you change this value, the LNB
immediately takes the appropriate position; thus you can recognize
whether the input has been appropriate.
The satellite Astra 1 does not reach elevation values smaller than approx.
14° anywhere within the reception range of the Oyster Vision. For other
satellites, however, this value may be still lower.
Caution: If you enter too large a value here, then your desired satellite,
particularly in northern regions of Europe, can possibly not be received
any more!
Arm adjustment
This option is intended for the service in order to make basic mechanical
adjustments at the system.
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