2.5 TVG Level

TVG (Time Varied Gain) compensates for propagation attenuation of the ultrasonic waves. It does this by equalizing echo pre- sentation so that fish schools of the same size appear in the same density in both shallow and deep waters. In addition, it reduces sur- face noise. Note that if the TVG level is set too high short range echoes may not be dis- played.

1.Turn on the power while pressing any key.

2.Press the A-SCOPE key three times. The start-up screen appears and shortly there- after the TVG SELECT display appears.

TVG SELECT

50kHz= 5(0~9) 200kHz= 5(0~9)

▲▼￿: 50kHz

ts: 200kHz

Figure 2-5 TVG select display

3.Operate the Cursor Pad to set level. The default TVG level for both 50 kHz and 200 kHz is 5.

4.Press the POWER key to escape.

2.6 Echo Offset

The echo offset feature functions to compen- sate for too weak or too strong echo level. If the on-screen echo level appears to be too weak or too strong and the level cannot be adjusted satisfactorily with the gain controls, do the following to adjust echo level:

1.Turn on the power while pressing any key.

2.Press the SIG LEV key three times. The start-up screen appears and shortly there- after the ECHO OFFSET display appears.

ECHO OFFSET

50kHz= 0(-99~ +99) 200kHz= 0(-99~ +99)

▲▼ : 50kHz

ts￿: 200kHz

Figure 2-6 Echo offset display

3.Operate the Cursor Pad to adjust level. The default echo offset is 40 for 50 kHz; 0 for 200 kHz.

4.Press the POWER key to escape.

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Furuno FCV-600L manual TVG Level, Echo Offset