Interphace ULTRASCAN PC90, Руководство по эксплуатации

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PC90 can accurately image features. Click on the
Auto box to turn Auto Range on and off. A check
in the box indicates that Auto Range is on. The
default setting is off.
In the manual mode, Ultrascan PC90 allows you to
choose one of twelve preset Ranges. Range can be
varied between 25 and 1000 feet, 8 and 300 meters,
or 4 and 160 fathoms. Select the desired Range by
sliding the pointer on the Range bar. The default
setting is the minimum range (25 feet).
In the Auto Range mode, Ultrascan PC90 will
adjust the Range automatically to keep the bottom
within the center three-quarters of the range scale.
If Ultrascan PC90 cannot find the bottom, it will
step through the Ranges until the bottom is found.
It is possible to make manual adjustments in the
Auto Range mode.
TIP
Leave the Gain and Range and/or
Alarm boxes open if you plan to make
frequent manual adjustments. Move a
box by dragging it to a desired position
NOTE
Auto Gain and Auto Range are always
turned off when you exit Ultrascan
PC90.
NOTE
Each Ultrascan PC90 gain setting is
actually a Time-Varied Gain (TVG)
curve which applies higher gains to later
returns. This is an important feature
which works to counteract the inherent
weakening of the acoustic signals with
distance from the transducer.