Advanced-Level Troubleshooting - Furuno FR-8045 Operator's Manual

6.6

Advanced-level Troubleshooting

This section describes how to cure hardware and software troubles which only quali-
fied service persons must do.
Problem
Power cannot be turned on.
Brilliance adjusted but no
picture.
Antenna not rotating.
Data and marks not dis-
played in transmit.
Set GAIN to the maximum
with A/C SEA set at mini-
mum. Marks and indications
appear but no noise or echo.
Marks, indications and noise
appear but no echo. (Trans-
mission leak show your ship
position is not present.)
Picture not updated or pic-
ture freeze-up.
Radar is correctly tuned but
sensitivity is weak.
Range changed but picture
does not change.
Range rings are not dis-
played.
Possible cause or check
points
1) Mains voltage/polarity
2) Power supply board
1) SPU Board
1) Antenna drive mechanism
1) SPU board
1) Signal between antenna and
display unit
2) IF amplifier
3) Video amplifier board
1) Magnetron
2) Modulator board
3) SPU board
1) Bearing signal generator
2) SPU board
3) Video freeze-up
1) [2nd Echo Rejector] is [ON]
2) Dirt on radiator face
3) Deteriorated magnetron
4) Detuned MIC
1) RANGE key has defaults
2) SPU board
3) Video freeze-up
1) Adjust their brilliance on the
[Brill/Color] menu.
2) SPU board
6. MAINTENANCE, TROUBLESHOOTING
Remedy
1) Correct the wiring and input
voltage.
2) Replace the power board.
1) Replace SPU Board.
1) Replace the antenna drive
mechanism.
1) Replace SPU board.
1) Check continuity and isola-
tion of coaxial cable.
2) Replace IF amplifier.
3) Check coax line for fasten
connection. If the connection
is good, replace SPU board.
1) Check magnetron current.
2) Replace modulator board.
3) Replace the SPU board.
1) Make sure that the signal ca-
bles are fastened.
2) Replace the SPU board.
3) Turn the radar off, then on.
1) Turn off the [2nd Echo Rejec-
tor] from the [Echo] menu.
2) Clean the radiator.
3) Check the magnetron current
with the radar transmitting on
48 nm range. If the current is
below normal, magnetron
may be defective. Replace
the magnetron.
4) Check the MIC detecting cur-
rent. If MIC detecting current
is below normal value, the
MIC may be detuned.
1) Try to operate the RANGE
key. If you can not operate
the RANGE key, replace the
keypad.
2) Replace the SPU board.
3) Turn the radar off, then on.
1) Replace the associated cir-
cuit board if unsuccessful.
2) Replace the SPU board.
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