Specifications; Antenna Unit; Display Unit - Furuno 841 MARK-2 Operator's Manual

SPECIFICATIONS

Antenna Unit

1. Radiator
Printed array
2. Radiator length
54 cm
3. Horizontal beamwidth
3.9
4. Vertical beamwidth
20
5. Sidelobe
-20 dB within main lobe
-23 dB outside main lobe
6. Polarization
Horizontal
7. Antenna rotation speed
24 rpm
8. Wind resistance
Relative wind speed 100 kts (51.5 m/s)
Transceiver Module
(contained in radome)
1. Transmitting tube
Magnetron MG5248, E3571 or
MAF1421B
2. Frequency
9410 MHz 30MHz, P0N (X band)
3. Peak output power
4 kW
4. Pulselength & pulse repetition rate
0.08 s, 2100 Hz (0.25, 0.5, 0.75, 1,
1.5 nm)
0.3 s, 1200 Hz (1.5, 2, 3 nm)
0.8 s, 600 Hz (3, 4, 6, 8, 12, 24, 36
nm)
5. Warm-up time
2:30
6. Modulator
FET switching method
7. I. F.
60 MHz
8. Tuning
Automatic or manual
9. Receiver front end
MIC (Microwave IC)
10. Bandwidth
7 MHz
11. Duplexer
Circulator with diode limiter

Display Unit

1. Indication system
PPI raster scan
2. Display
8-inch diagonal LCD, STN semi-
transparent, yellow mode
3. Range scales (nm)
Range, Ring Interval: 0.125(0.0625),
0.25(0.125), 0.5(0.125), 0.75(0.25),
1(0.25), 1.5(0.5), 2(0.5), 3(1), 4(1),
6(2), 8(2), 12(3), 16(4), 24(6), 36 (6)
4. Bearing resolution
4
5. Bearing accuracy
Better than 1
6. Range discrimination
Better than 25 m
7. Range ring accuracy
0.9% of range in use or 8 m,
whichever is larger
8. Minimum range
Better than 37 m
9. Markers
Heading marker, Bearing scale, Range
ring, VRM, EBL, Waypoint (option),
Tuning indicator, Alarm zone, Cursor
10. Alphanumeric indication
Standard: Electronic Bearing Line
(EBL), Echo Stretch (ES), Rain
Clutter Rejection (FTC), Alarm
(G), Interference Rejection (IR),
vii