Furuno FR-2105 Operator's Manual page 41

The zone has a fixed width of 0.5 nm in the radial direction (depth) and is adjustable only
within 3.0 to 6.0 nm from own ship. On the R-type, the outer and inner boundaries can be set
at any distance. On any radar type, the sector of the zone can be set anywhere between 0 and
360 degrees in any direction.
To set a target alarm zone:
1. Place the cursor (+) at point "A" (see figure below) using the trackball.
2. Press the RADAR MENU key to show the FUNCTION 1 menu.
3. Press [2] key to set start point (point "A") of the alarm zone. The message TGT ALARM 1
(or 2) SET appears at the bottom-right corner of the screen.
4. Move the cursor (+) to point "B" and press the [2] key again. Then, the target alarm zone as
illustrated is created and the label TGT ALARM 1 (or 2) appears instead of TGT ALARM
1 (or 2) SET at the lower-right corner of the screen.
Note: If you wish to create a target alarm zone having a 360-degree coverage around own
ship, set point "B" in almost the same direction (approx. ±3°) as point "A" and press the [2]
key.
If you change the range scale to less than half of the TAZ, the warning TGT ALARM 1 (or
2) OUT appears instead of TGT ALARM 1 (or 2).
5. Two alarm zones can be set as described above. Press [ENTER] and [2] keys in that order
while displaying the FUNCTION 1 menu and repeat the above steps.
000
350
340
330
320
310
300
A
290
280
270
260
250
240
230
220
210
200
190
180
Acknowledging alarm
A target entering the watch zone produces both visual (flashing) and audible (beeping) alarms.
To silence the audible alarm, press [2] key shortly on the FUNCTION 1 menu and the label
TGT ALARM 1 ACK replaces TGT ALARM 1 on the display.
This will deactivate the audible alarm but will not stop the flashing of the target in the guard
alarm zone. To reactivate the audible alarm, press [2] key again on the FUNCTIONS 1 menu.
When an external buzzer is connected, the audible alarm does not stop until deactivation of the
guard alarm.
TAZ
010
020
030
040
050
060
070
B
080
090
100
110
120
130
140
150
160
170
Target alarm zone (TAZ) can be set in any sector
between 3 and 6 nm on IMO-type, or anywhere on
the R-type.
When the radar has an ARPA board ARP-26, a total
of 4 alarm zones (2 each TAZ and GZ) may be set.
The 2nd TAZ or 2nd GZ is available only when the
1st TAZ or 1st GZ is valid.
-1.24-