Interphase Twinscope Operation Manual page 55

NOTE: The FISH Alarm is activated and
cleared independant of other alarms.
When activated, the softkey labeled
"FISH" will be shown in reverse video
(white on black). Press the softkey again to
clear the FISH Alarm
to manually adjust the sensitivity, the Twinscope turns
off the AUTO sensitivity mode and it will remain off
until the AUTO soft key is again selected. Note: when
AUTO mode is turned on, the word will be displayed in
reverse video (white letters on a black background). To
exit the sensitivity menu and save your adjustments,
simply press the soft key labeled "LAST" to return to the
main forward looking menu.
Hardness (White-Line)
If the softkey labeled "HARD" is pressed, the display
will show the bottom as a thin line separated by a shaded
area. This mode can be used to find detail close to the
bottom or to indicate the bottom composition. A thick
shaded line indicates a hard or rocky bottom and a thin
shaded line indicates a softer bottom.
Alarm Adjustment
In the forward looking display or view, alarms may be set
for targets which are shallower than, deeper than, or
within a specific zone of adjustable depth settings.
To adjust or clear the alarm settings, press the soft key
labeled "ALARM" to bring up the forward looking
Alarm menu choices. Pressing the "Deep" or "Shal." soft
keys brings up sub-menus to set, adjust or clear the
alarms. As either the " " or " " keys are pressed and
held down, or the front panel knob is rotated, a vertical
bar on the left side of the screen (just below the boat icon)
shows the area covered by the depth alarm. Whenever a
solidly displayed target appears at the same depth as that
covered by the alarm bar, the audible alarm sounds to
warn you of underwater targets or changing bottom
conditions.
The S
hallow Alarm is often used to alert the user to
shallowing bottom conditions and the presence of under-
water targets such as fish. The Deep Alarm is often used
in conjunction with the Shallow Alarm to define a depth
range. If the depth becomes less or greater than the alarm
settings, the audio alarm will sound as a warning. A Zone
Alarm can be created by using both the Shallow and Deep
Alarms. If the Shallow and the Deep alarm bars on the
left side of the display are overlapped (that is, the Shallow
Alarm bar overlaps the Deep Alarm bar) a new Zone
Alarm will result and be displayed. Press the "CLEAR"
soft key to clear the alarm or alarms you previously set.
Press "CLEAR" in the main alarm menu to clear all
alarms simultaneously, or press "CLEAR" in the sub-
menus to clear the selected Shallow or Deep Alarm.
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