Furuno 2127 - Manual (Page 41)

3. SETTING AND ADJUSTMENT
3-3
3.3 Heading Alignment
You have mounted the antenna unit facing straight ahead in the direction of the bow.
Therefore, a small but conspicuous target dead ahead visually should appear on the
heading line (zero degrees).
In practice, you will probably observe some small bearing error on the display because of
the difficulty in achieving accurate initial positioning of the antenna unit. The following
adjustment will compensate for this error.
000 010 020
030
040
050
060
070
080
090
100
110
120
130
140
150
160 170 180 190 200
210
220
230
240
250
260
270
280
290
300
310
320
330
340 350 α Target
α Correct bearing
relative to heading
Antenna mounted error
to port (HDG SW
advance) Picture appears
deviated clockwise.
000 010 020
030
040
050
060
070
080
090
100
110
120
130
140
150
160 170 180 190 200
210
220
230
240
250
260
270
280
290
300
310
320
330
340 350 β Target
β
Apparent position
of target
Antenna mounted error
to starboard (HDG
SW delayed) Picture appears
deviated counterclockwise.
Correct
bearing
relative to
heading
Apparent
position
of target
Heading alignment
1. Select a stationary target echo at a range between 0.125 and 0.25 nm, preferably near
the heading line.
2. Operate the EBL control to bisect the target echo.