Furuno COLOR VIDEO PLOTTER 1833C Operator's Manual page 200

Sounder system setup menu description (con't from previous page)
Item
TVG TVG (Time Varied Gain)
(50 kHz, 200 compensates for propagation
kHz) attenuation of the ultrasonic
waves. It does this by equalizing
echo presentation so that fish
schools of the same size appear in
the same density in both shallow
and deep waters. In addition, it
reduces surface noise. Note that if
the TVG level is set too high short
range echoes may not be
displayed.
Echo Offset If the on-screen echo level
(50 kHz, 200 appears to be too weak or too
kHz) strong and the level cannot be
adjusted satisfactorily with the gain
control, adjust echo offset to
compensate for too weak or too
strong echoes.
Bottom Level If the depth indication is unstable
(50 kHz, in automatic operation or the
200 kHz) bottom echo cannot be displayed
in reddish-brown by adjusting the
gain control in manual operation,
you may adjust the bottom echo
level detection circuit, for both 50
kHz and 200 kHz, to stabilize the
indication. Note that if the level is
set too low weak echoes may be
missed and if set too high the
depth indication will not be
displayed.
KP Pulse Selects source of keying pulse.
Smoothes echoes to present
Smoothing
stable display. The higher the
setting the greater the smoothing.
TLL Output Outputs current position to plotter
where it is marked with TLL mark.
Use soft key to output TLL.
SENSOR Offsets speed, depth and water
SETUP temperature indications and speed
soft key of sound.
(See next
page.)
Description
5. CUSTOMIZING YOUR UNIT
Settings
0-9
-50 - +50
-100 - +100
Internal, External
(See installation
manual.)
SM1-SM4, OFF
ON, OFF
See next section for details.
Default
Setting
3 (both 50 kHz
and 200 kHz)
0 (both 50 kHz
and 200 kHz)
0 (both 50 kHz
and 200 kHz)
Internal
SM3
ON
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