Antenna Unit: Fb-1500/1250; Overview; The Functions For The Major Module - Furuno Felcom 250 Service Manual

11.2 Antenna unit: FB-1500/1250

11.2.1. Overview

1. The Antenna unit for FELCOM-500 is "FB-1500", and the one for FELCOM-250 is
"FB-1250". The circuit configuration and the operations are almost the same.
EIRP
G/T
Antenna gain
Beam width
Antenna
weight
Size
Power
consumption
Note)
Sensor
2. GPS data or Heading data will not be used for Antenna control such as satellite
searching or tracking.
However, GPS data is used for the Fleet Broadband system.
3. The Antenna unit has a tracking algorithm equipped which will acquire the satellite
signal by itself without having to execute any operation from satellite searching until
satellite tracking.

1. The Functions for the Major module

HPA Module:
Power amplifier
Front end Module:
An assembly of ATB (Antenna Tracking Board) and LNA (Low Noise
Amplifier). ATB controls the Antenna unit and communicates with the
Communication unit.
Table 11.2.1 The major differences between the Antenna units
FB-1500
22 dBW
-7 dB/K
Rx: 17.6 dBi, Tx: 18.2 dBi
Approx. 22 degree (-3 dB)
21 kg
H : 728 (attachment included)
φ : 653
Approx. 40 W
Clinometer (Inclination sensor)
Note) The operations are the same for both sensors.
11-15
11.2 Antenna Unit: FB-1500/1250
FB-1250
15.1 dBW
-15 dB/K
Rx: 11.6 dBi, Tx: 12.4 dBi
Approx. 50 degree (-3 dB)
6.5 kg
H : 349
φ : 410
Approx. 40 W
FB-1250:Rate Gyro