Adjusting the STC level ([STC] controls)
Adjusting surface or bottom STC level with
the [STC] controls
Rotation of the [STC] controls adjusts the STC level, thus suppressing
noise due to the presence of dirt, air bubbles, and other foreign
substances near the sea level.
Two [STC] controls are provided: for high-frequency use and for low-
Depending on the desired frequency, adjust the STC level using the
appropriate [STC] control. To increase noise suppression force, rotate
the [STC] control clockwise. The standard setting of the control is "4" or
Lower STC level
To change the STC operating range, change the setting of "STC
range" in the fishfinding menu. For further details, see "Setting the
STC operating range" on page 48.
The STC level can be adjusted by changing the STC operating range.
Either 50 m,100 m, 150 m, or 200 m can be selected as the operating
range. Select 50 m for normal operating conditions. A wider operating
range mainly displays larger schools of fish, and a narrower range
displays smaller schools of fish as well.
Higher STC level
The small semi-fixed type
controls located to the left of
the [GAIN] controls shown
above are the [STC] con-
trols. Use a small Phillips
screwdriver to adjust the