Instruction manual

Chapter 2 How to use the menu CVS-128
2-14 0093112802-00
2.18 Explanation of Menu Item
The various items in the menu are explained.
Inner-hull
The reduction in sensitivity due to signal
attenuation in inner-hull use can be corrected.
(Setting: - 50 ~ 50: through-hull: 0)
1 Press the [MENU] key.
2 Select the [Adjust] → [Gain (TD)]. (See [2.1
How to operate the menu])
3 Press the [ ] key. The image displays
bottom only. It may show very strong fish
targets.
4 Set a value to display the sea bottom
continuously without interruption. For high
frequency, turn [GAIN (HF) knob] and for
low frequency, turn [GAIN (LF) knob].
5 Press the [MENU] key to close the menu.
Caution: Gain (TD) setting value widely
varies upon installation conditions
such as material of hull and
installation method. Low frequency
(50 kHz) may not be used due to large
signal attenuation.
TVG
The TVG adjusts the difference of strength
between echoes reflected from the shallower
depth and echoes reflected from deeper depth
so that the reflection can be uniformed.
The deeper the depth is, the reflected signal of
echo sounder becomes weaker due to
attenuation. Thus, comparing with the signal
reflected from the same size fish, the signal
reflected from the fish in the shallower depth is
stronger than that in the deeper depth. The
TVG adjusts the echo signal reflected from the
shallower depth to be equal to that reflected
from deeper depth by decreasing the receiver
gain so that the effect that the strength of echo
signal reflected from the shallower depth looks
the same as that reflected from the deeper
depth provided. The level of adjustment due to
the depth increases in the order of weak →
medium → strong. When set to "Strong", the
TVG provides strongest effect that reduces
various noises around oscillation line.
1 Press the [MENU] key.
2 Select the [Adjust] → [TVG]. (See [2.1 How
to operate the menu])
3 Press the [ ] key.
4 Select the [weak], [medium], [strong].
(Press the [ ] key or [ ] key)
5 Press the [MENU] key to close the menu.
Caution: When the setting of [Gain
select] is either one of [Cruising] or
[Fishing], it cannot be selected.
Change the TX power
The strength of transmission output (power)
can be changed.
When the noise of interference with the
neighboring echo sounder occurs, if the powers
of transmission outputs at both sides are
weakened, the interference noise can be
suppressed.
In the [Auto] setting, the transmission output is
automatically adjusted.
Bottom
Gain (TD)
Gain (TD) L
Gain (TD) H
TVG
Weak
Medium
Strong