Major Functions Of Boards; Transceiver Unit: Fs-Xx75T - Furuno FS-1575 Service Manual

7.1.3 Major Functions of Boards

1. Transceiver unit: FS-xx75T

Board
Type
Name
TX 05P0856
05P0866A
DRV
05P0866B
05P0867A
PA
05P0867B
05P0868
COMB 05P0869
05P0870A
TX FIL
05P0870B
05P0876
CONFIDENTIAL (internal use only)
This confidential document is used only by FURUNO authorized persons.
It is strictly prohibited to reproduce the document in whole or in part without prior written permission of FURUNO.
Table 7.1.2 Transceiver Unit Built in Boards
Applicable
Model
Converts a 36-kHz IF signal from T-CPU to RF frequency.
The maximum output is 12dBm into 50-ohm dummy load.
The TX board has a built-in 36-MHz reference oscillator to
Common
output this signal to the RX, WR1, and WR2 boards as
reference PLL frequency. The TX board is also used to operate
the ALC; output power control.
Divides DRV board output power into two outputs to deliver
each one to the PA boards, respectively, at a level of 10 to
20W. The AMP circuit configuration and AMP gain are the
same as those for the FS-2575 system.
FS-5075
Furthermore, this board has built-in Temp detection circuit,
V-SWR detection circuit, divider imbalance detection circuit,
and circuit that reduces output power according to the
PROTECT signal from the PA-IF board.
Outputs power to the PA boards at a level of 15 to 25W.
The difference from the DRV board used in the FS-5075
FS-2575 system is that the DRV board used in this model has only one
DRV output port. Furthermore, this board has no built-in
divider imbalance detection circuit.
Outputs power at a level of 250 W.
( TX output power: 500W generated by combining two outputs
from the PA board in the next COMB board stage. )
FS-5075 This PA board has the same AMP circuit configuration and
AMP gain as that used in the FS-2575 system.
Furthermore, this board has built-in Temp detection circuit,
V-SWR detection circuit, and PA IC/PA VC detection circuit.
Provides the same function as above, except for the type of
FS-2575 input transformer.
This PA board outputs power at a level of 250W.
Outputs power at a level of 150W.
FS-1575 This PA board has built-in Temp detection circuit, V-SWR
detection circuit, and PA IC/PA VC detection circuit.
Generates 500W power by combining two outputs of 250W
power from the two PA boards. This COMB board has a
FS-5075
built-in imbalance detection circuit that detects PA output
impedance.
Consists of eight Low-pass filters to reduce harmonic caused
by the DRV and PA boards.
This TX FIL board has built-in BK relay used to switch
FS-5075
between transmitting and receiving signal, I/O V-SWR
detection circuit, and 50-ohm dummy load used to conduct
self-tests.
Provides the same function as above, except for the type of
FS-2575
input connector.
This TX FIL board has the same circuit configuration as
FS-1575
05P0870A/B, but different in power capacity.
7-6
7.1 System Configuration
Function