Chapter 8. Maintenance; Self-Test And Error Message; Daily Test; Tx Power - Furuno FM-8800D Service Manual

8.1 Self-test and Error Message

8.1.1 Daily test (Self-test)
Press [SHIFT] -> [TEST] key to carry out the test.

** DAILY TEST **

TX POWER

TX/RX PCB
CPU PCB : OK
CH70 RX PCB
DUP RX PCB
1. TX POWER
This test stores the last minute state of TX output (F-VSWR and R-VSWR) before the
self-test in memory and checks to see if the output value is over the designated value or
not. Press PTT switch with Hi power before carrying out the self-test and stores the state
of TX output memory.
If you turn on the power and carry out a self-test without transmitting at all, ''NO
CHECK'' will appear. If the output is less than 8 W, ''NG'' will appear which means
there is a problem with either PA module or TX/RX board (05P0774A, B).
- OK/NG indication: assessed by approximately 8 W.
- NO CHECK: indicated with self-test is carried out with no transmission.
CM Coupler
Tx out

Chapter 8. Maintenance

Test in progress
: OK
: OK
: OK
: OK
OK means over approximately 8 W.
PA
DRIVE
RA35H1516M
U2
U1
(DCS3D20)
PWR CONT
Q2/12
F-VSWR DET
R52
CR8
U3(1/2)
R-VSWR DET
CR103
CR6
U3(2/2)
Fig. 8.1.1 TX POWER Detector Circuit
Distress Alarm, LED of [Distress] button lights and
LED of ALARM blinks. To be OFF, press
[CANCEL] key
When PTT switch is not pressed before
the test, "NO CHECK" appears.
Displays only FM-8800D
TX/RX
05P0774A, B
Q1,5
UN LOCK
(From U12: PLL IC)
TEST ON
PWR CONT
U4
F VSWR
R VSWR
8-1
8.1 Self-test and Error Message
CPU
05P0773
U30
CPU
DA
FROM
AD