Tvg Level; Echo Offset - Furuno FCV-582L Operator's Manual

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 ZOOM key three times. The
start-up screen appears and shortly there-
after the TVG SELECT display appears.
TVG SELECT
50kHz= 5(0
200kHz= 5(0
: 50kHz
- + : 200kHz
Figure 2-5 TVG select display
3. Operate appropriate key among [ ], [ ],
[+] or [–] to set level.
4. Press the POWER key to escape.
18
9)
9)

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 control,
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
200kHz= 0(-99
: 50kHz
- + : 200kHz
Figure 2-6 Echo offset display
3. Operate appropriate key among [ ], [ ],
[+] or [–] to set level.
4. Press the POWER key to escape.
+99)
+99)