Advanced-Level Troubleshooting - Furuno FR-8062 Operator's Manual

6. MAINTENANCE & TROUBLESHOOTING
6.6

Advanced-level Troubleshooting

This paragraph describes how to cure hardware and software troubles which should be carried
out by qualified service personnel.
Note: This radar equipment contains complex modules in which fault diagnosis and repair down
to component level are not practicable by users.
Problem
Power turned on but
radar does not work
Brilliance adjusted
but no picture
Antenna not rotating
Data and marks not
displayed in Transmit
status
Adjust GAIN with
SEA set at minimum.
Marks and indications
appear but no noise
or echo
Marks, indications
and noise appear but
no echo (Transmis-
sion leak repre-
senting own ship
position is absent)
Picture not updated
or picture freeze-up
Radar is properly
tuned but sensitivity is
poor
6-6
Advanced-level troubleshooting
Probable cause or
check points
1) Blown fuse.
2) Mains voltage/polarity
3) Power supply board
1) SPU Board
1) Antenna drive mechanism
1) SPU board
1) IF amplifier
2) Signal cable between
antenna and processor unit
3. Video amplifier board
1) Tx fuse
2) Magnetron
3) Modulator board
4) SPU board
1) Bearing signal generator
2) SPU board
3) Video freeze-up
1) Deteriorated magnetron
2) Detuned MIC
3) Dirt on radiator face
4) 2nd trace echo rejector is
ON.
Remedy
1) Replace blown fuse.
2) Correct wiring and input voltage.
3) Replace power supply board.
1) Replace SPU board.
1) Replace antenna drive mechanism.
1) Replace SPU board.
1) Replace IF amplifier.
2) Check continuity and isolation of coaxial
cable.
Note: Disconnect the plug and lugs at both
ends of coaxial cable before checking it (by
ohmmeter).
3) Check coax line for secure connection. If
connection is good, replace SPU board.
1) If fuse has blown, replace it. If it blows
again, the modulator or associated circuit
may be defective.
2) Check magnetron current.
3) Replace modulator board.
4) Replace SPU board.
1) Check that signal cables are fastened
securely.
2) Replace SPU board.
3) Turn the radar off and on.
1) With the radar transmitting on 48 nm
range, check magnetron current. If cur-
rent is below normal, magnetron may be
defective. Replace the magnetron.
2) Check MIC detecting current. If it is below
normal value, MIC may have become
detuned. MIC must be tuned
3) Clean radiator.
4) Turn off the 2nd trace echo rejector, on
the Echo menu.