Advanced-Level Troubleshooting - Furuno 1835 Operator's Manual

6.5

Advanced-level Troubleshooting

This section describes how to cure hardware and software troubles which the qualified
service persons must do.
Problem
Power cannot be
turned on.
Brilliance adjusted
but no picture.
Antenna not rotat-
ing.
Data and marks
not displayed in
transmit.
Set GAIN to maxi-
mum with A/C SEA
set at minimum.
Marks and indica-
tions appear but no
noise or echo.
Marks, indications
and noise appear
but no echo.
(Transmission leak
representing your
ship position is ab-
sent.)
Picture not updat-
ed or picture
freeze-up.
Advanced-level troubleshooting
Probable cause orcheck
points
1) Mains voltage/polarity
2) Power supply board
1) SPU Board
1) Antenna drive mechanism
1) SPU board
1) Signal cable between an-
tenna 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
6. MAINTENANCE, TROUBLESHOOTING
Remedy
1) Correct the wiring and input
voltage.
2) Replace power supply
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 connection is
good, replace SPU board.
1) Check magnetron current.
2) Replace modulator board.
3) Replace SPU board.
1) Check that signal cables
are fastened.
2) Replace SPU board.
3) Turn off and on the radar.
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