Furuno FA-2805, Operator'S Manual

Page: 92 / 169

5-4
Problem Check point and
probable cause Remedy
Interference rejector
inoperable (interference
rejection level not
displayed) 1. Bad contact of key
2. SPU Board
3. Mother Board 1. Repair contact of key.
2. Replace SPU Board.
3. Replace Mother Board.
Echo stretch ineffective
(Neither "ES1" nor "ES2" is
displayed.) 1. Bad contact of key
2. SPU Board 1. Repair contact of key.
2. Replace SPU Board.
Only 2 parallel index lines
(6 lines wanted) 1. Incorrect setting of index
line interval 1. Set index line interval referring to
paragraph 1.26.
Range rings are not
displayed. 1. Press RINGS key to see if
intensity is increased.
control to see if intensity is
increased.
2. Bad contact of key
3. SPU Board 1. Replace associated circuit board if
unsuccessful.
2. Replace keypad.
3. Replace SPU Board.
Key beep inaudible 1. Improper setting on
RADAR 2 menu 1. Adjust key beep level on
RADAR 2 menu referring to
paragraph 1.32.
Poor discrimination at
range 1. Sea clutter control not
functioning properly. 1. Improper setting of A/C SEA
control. If A/C SEA is seen only
at very close range, suspect
inaccurate frequency of
crystal oscillator.
True motion presentation
not working correctly 1. Poor contact of MODE
key.
2. Selection is not accessed.
3. Speed entry is incorrect.
4. TM display inaccurate
1. Try to press MODE key a little
harder.
2. Press MODE key until "TM"
appears.
3. Enter correct own ship speed
referring to paragraph 1.24.
4. Make sure that speed and compass
inputs are accurate.
Target not tracked correctly 1. Poor definition of targets in
sea clutter
1. Adjust A/C SEA and A/C RAIN
controls referring to paragraphs
1.13 and 1.14.