Furuno FA-2805, Operator'S Manual

Page: 35 / 169

1-20
2. Press the OFF CENTER key. Then, the
sweep origin is off-centered to the cur-
sor position.
3. To cancel off-centering, press the OFF
CENTER key again.
HL
OFF
ECHO
TRAILS
MODE
ORIGIN
MARK
VECTOR
TRUE/
REL
VECTOR
TIME
GUARD
ALARM
EBL
OFFSET
OFF
CENTER
Inside mode panel
Cursor
Cursor
Off-centered to cursor position – Max.
offset
100% of range in use on R-type
75% of range in use on IMO-type
The picture cannot be off centered in
the true motion mode.
1.22 Echo Stretch
On long ranges target echoes tend to
shrink in the bearing direction, making
them difficult to see. On short and me-
dium ranges such as 1.5, 3 and 6 nm
scales, the same size targets get smaller
on screen as they approach the own ship.
These are due to the inherent property of
the radiation pattern produced by the an-
tenna. To enhance target video, use the
echo stretch function. There are two
types: echo stretch 1 for long range de-
tection and echo stretch 2 on 1.5-6 nm
scales.
To activate the echo stretch:
1. Press the RADAR MENU key on the
plotting keypad to show the FUNC-
TIONS menu.
2. Press the [2] key to select 2 ECHO
STRETCH.
3. Press [2] until Echo Stretch option 1, 2
or OFF as desired is highlighted.
4. Press the ENTER key to conclude your
selection followed by the RADAR
MENU key to close the FUNCTIONS
menu.
Hit [RADAR MENU].
* R-type only
1 PULSE WIDTH
2 ECHO STRETCH
3 ECHO AVERAGE
4 PANEL DIMMER
5 ECHO COLOR
6 SHIP'S SPEED
7 INDEX LINES
8 SET/DRIFT
9 BRILLIANCE
0 [SYSTEM SETTING 1]
1/2
OFF/1/2
OFF/1/2/3
OFF/DIM/M/BRT
YEL/GRN/COLOR*
LOG/NAV*/MAN
NO.2 VRM/MAN
OFF/MAN
SET 000.0
DRIFT 00.0 KT
[FUNCTIONS 1]
(a) Echo stretch 1 for 12 nm range
and above
Enlarged in bearing
(circumferential)
direction with ES1
(b) Echo stretch 2 for 1.5–6 nm ranges
Enlarged with
ES2
If a distant target
is hard to see, use
ES 1.
If a target becomes
smaller as it
approaches own
ship, use ES 2.
Notes:
1) If the 1.5 nm range is preset for
pulsewidth of S1 (0.08
µ
s) or S2 (0.2
µ
s), and the 3 nm scale for S2 (0.2
µ
s),
the echo stretch function is not avail-
able on these range scales.