Tx Fil (Fs-1575, Fs-2575, And Fs-5075); Coupler (Fs-1575, Fs-2575, And Fs-5075) - Furuno FS-1575 Service Manual

8. TX FIL (FS-1575, FS-2575, and FS-5075)

This test menu is used to conduct the TX FIL board tests by switching the band to 1, 3,
4, 6, 8, 12, 18, and 22 MHz.
The "TX FIL" tests are conducted with "TX IF signal: 36 kHz" outputted from CODEC,
mode set to "J2B," and power data set according to the model of the system in use.
The TX FIL board is determined to be OK when the detected level of the "CHECK IN
VR (FIL-IN VR)" signal is not higher than a specified level in all bands of the TX FIL
board and that of the ALC has reached above their specified level.
The detected level can be checked by selecting [MENU] -> 9.SERVICE -> 3.RT
SETUP -> 1.SETUP -> 2.SELF CHECK -> "FILTER."
Furthermore, the TX, DRV, and PA boards are set to transmission "ON," and the TX FIL
board output is terminated with the 50 ohm dummy load.
CHECK IN VR
ALC

9. COUPLER (FS-1575, FS-2575, and FS-5075)

This test menu allows for conducting coupler test without using the RF signal.
The coupler is determined to be "OK" when the TUNE signal is sent to the ATU and the
TUNE OK signal from the ATU results in "ERROR." In other words, this test is
conducted to check for the connection of the coupler.
FS-xx75T
T-CPU
MOT
CPLD
CPU
FPGA
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.
TX FIL
L1
PA
B.P.F
x 8 Band
IN VR/VF OUT VR/VF
B.P.F
ALC
U1
ALC
R43
Fig. 6.1.13 TX FIL CHK Circuit Diagram
ATU
TUNE
TUNE OK
U11
RX GND CPU
Not used
ANT BK
Not used
RX GND
ANT BK
Fig. 6.1.14 COUP CHK Circuit Diagram
6-14
K17
L18
K19
BK ON
K18
CHECK ON
R44
51 ohm/35W
COUP
TUNE
TUNE OK
No output
6.1 [MENU] -> TEST
ANT
RX RF
H: TUNE OK
25ms
L: TUNE ERROR
25ms
.
RF ( = 10W)
.