L-3 Communications Navigation Echosounder LAZ 5100 User Manual
Page 42
Page 4-7
L-3 ELAC Nautik
4.4
ALTERING SYSTEM PARAMETERS AND SETTINGS
When the system is switched OFF, parameters selected are stored in the system's memory. When
the system is switched ON again, these parameters will be retrieved and used (see NOTE below).
NOTE:
The "DIM" setting is not stored, a pre-set default setting is used when the
system is switched ON. With two channel systems, channel 1 is the default
channel at start-up.
4.4.1
GAIN, RANGE AND DIM SETTINGS
GAIN (amplification), RANGE (depth range) and DIM (display area backlighting and keypad
illumination) settings are made by pressing the relevant keys. There are two keys for each setting,
one marked with an arrow pointing upwards and one marked with an arrow pointing downwards.
Pressing these keys as described below will alter the present setting. The new setting will appear
briefly on the display area directly above the key which was pressed and the effects of a change
can be observed directly on the display area. Pressing the key a second time will alter the setting
by a further unit.
GAIN:
The unit is fitted with an automatic gain control circuit for the data processing which is always
activated when the unit is switched on. The GAIN setting only influences the displayed echo
information. The GAIN value can be altered between 1 and 10, whereby 1 is the lowest and 10 the
highest gain (amplification) factor.
If the sea bed trace appears too weak, the GAIN level must be increased to give a clear
presentation. If there is a lot of "noise" to be seen on the display area, the GAIN level must be
decreased. To increase the GAIN level, press the GAIN key V To decrease the GAIN level,
press the GAIN key W. The value set will appear on the display area above the key (between 1
and 10). Pressing the same key a second time will cause the value to increase or decrease by one
further unit. Repeat the procedure until a satisfactory sea bed trace is achieved.
In some cases it can be useful to work with manual instead of automatic gain. Manual gain setting
is explained in chapter 4.5.2.