Furuno FCV-1200L Operator's Manual page 33

2. Press the [!] or ["] to select HF•FREQ ADJ or LF•FREQ ADJ whichever is appropriate.
3. Press the [-] or [+] key to set appropriate value in the setting window so that interference
disappears. (The setting range is -10.0% to +10.0%, however the lowest setting available
for the 68 and 200 kHz transducers is -4.5%.)
To adjust interference suppression level finely, go to step 4.
If the interference suppression is sufficient, go to step 7.
4. Press the [!] or ["] key to close the setting window.
5. Press the ["] key to select HF•NOISE LIM or LF•NOISE LIM whichever is appropriate.
6. Press the [-] or [+] key to select the noise rejection setting in the setting window.
N3 provides the highest level of interference suppression.
7. Rotate the [FUNCTION] switch to select EXIT.
Note: Turn the noise limiter off when no interference exists, otherwise weak echoes may be
missed.
N1 N2 N3
OFF
Signal level setting window
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