MDC-3560P/3510P Series
Chapter 8
TROUBLE SHOOTING AND ON BOARD SERVICING
93142002-01
8-3
8.3 Trouble shooting
This section provides information required to fix or diagnose the faulty part in
RA73P/74P radar systems.
8.3.1 First-line faultfinding
Use the following tables that show brief diagnosis schedule to assist first-line servicing
on board the ship.
Table 8.3 Primary faults
Description of fault
Possible cause of failure
Corrective measures
Radar does not turn on
1. Power cable is disconnected.
2. Power supply voltage is outside of
the specified value.
3. Main fuse is blown.
1. Connect the power cable and
secure the cable plug
connection.
2. Use properly rated power
supply.
3. Replace the fuse with new
one.
Radar turns on but
nothing displayed on the
screen
1. Brilliance control is set at
minimum position.
2. CRT is defective.
3. CRT driving circuits are defective.
1. Turn the brilliance control CW
to set proper brilliance.
2. Call for service.
3. Call for service.
Table 8.4 Possible faults
Description of faults
Possible cause of failures
Corrective measures
Screen is dark
1. Brilliance of the screen is not
properly set.
2. CRT is getting weak.
3. CRT driving circuits are defective.
1. Turn the brilliance control
CW to set proper brilliance.
2. Call for service.
3. Call for service.
No targets shown
1. Tuning is deviated.
2. Video contrast is poor.
3. Transceiver is defective.
1. Re-adjust tuning referring to
para 6.2.14 and 6.2.15 in
this manual.
2. Re-adjust contrast referring
to para 6.2.1
3.
Turn on Performance
Monitor to isolate the faulty
section.
4. Call for service.
Targets are weak
1. Tuning has drifted.
2. Magnetron or MIC is faulty.
1. Re-adjust tuning referring to
para 6.2.14 and 6.2.15 in
this manual.
2. Call for service.
No markers (HL, EBL,
VRM, Range Rings,
Parallel Index Line,
Alarm Zone)
1. Marker video contrast is not
properly set.
2. Logic board is defective.
1. Re-adjust Marker contrast
referring to para 6.2.2.
2. Call for service.
Heading Line is missing
1. Heading Line signal is not applied to
the display.
2. Heading Line signal is not
generated. Fault on HL Generator
PCB.
1. Check for cable connections
for HL signal at antenna and
display
units.
2. Call for service.
