Furuno 1942 MARK-2 - Manual (Page 24)

3-5
3. Operate the omnipad to set the cursor on
point C (or D). See Figure 3-8 (3).
4. Press the [GUARD] key. The asterisk dis-
appears. See Figure 3-8 (4).
Guard zone
to set
* G (IN)
(2) Drag cursor to
top left corner of
zone and press
[GUARD].
Asterisk blinking
Drag cursor
here.
(1) Mentally create
the guard zone to set.
G (IN)
(3) Drag cursor to
bottom right corner
of zone and press
[GUARD].
(4) Guard zone
completed.
G (IN)
Guard
zone
Drag cursor
here.
A
B C
D
A
C
Figure 3-8 How to set the guard zone
Silencing the audible alarm
Any radar targets violating the guard zone
will trigger the audible alarm. You can silence
the audible alarm by pressing the [GUARD]
key. When this is done, “G(ACKN)” replaces
“G(IN).” This means the alarm is acknowl-
edged. Press the key again to reactivate the
alarm. You may select minimum echo stregth
which triggers the guard alarm. This can be
done at “20, Alm Sence Lv” on the “OTHER
MENU.”
Cancelling the guard zone and
guard alarm
Press and hold down the [GUARD] key until
the guard zone disappears.
Notes on the guard alarm
¡ The alarm is a useful anti-collision aid, but
does not relieve the operator of the re-
sponsibility to also keep a visual lookout
for possible collision situations.
¡ When the radar range is less than one
half of the guard zone range, the guard
zone disappears and “G (IN)” or “G (OUT)”
appears in inverse video. If this happens,
raise range to re-display the guard zone.
¡ A target echo does not always mean a
landmass, reef, ships or surface objects
but can imply returns from sea surface or
precipitation. As the level of these returns
varies with environment, the operator
should properly adjust the A/C SEA, A/C
RAIN and GAIN to be sure the alarm sys-
tem does not overlook target echoes.
3.8 Watchman
The watchman function periodically transmits
the radar for one minute to check for targets
in a guard zone. If it finds change in the zone
from the previous transmission it transmits
the radar continuously. This feature is useful
when you do not need the radar’s function
continuously but want to be alerted to radar
targets in a specific area.
St-by
5, 10 or
20 min
Tx
1 min
Tx
1 min
St-by
5, 10 or
20 min
Watchman
starts.
Figure 3-9 How watchman works
How watchman works
When the time selected for the watchman rest
period has elapsed, the radar automatically
transmits for one minute to check the condi-
tion inside the guard zone. If there is no
change, the radar goes into stand-by.
(“WATCHMAN” appears during stand-by.) If
there is change, the radar sounds the audible
alarm, cancels the watchman function and
transmits continuously.