Onwa KF-667 - Manual (Page 15)

2.4 Adjusting Gain
The [GAIN] control adjusts the sensitivity of the receiver. Adjust it so that a slight amount of noise
remains on the screen. Generally, use a higher gain setting for greater depths and a lower
setting for shallower waters.
Note: The [GAIN] control is inoperative when the automatic mode is active.
Gain too high Gain proper Gain too low
2.5 Automatic Operation
Automatic operation is useful when you are preoccupied with other tasks and do not have time to
adjust the display.
2.5.1 How it works
The automatic function automatically selects the proper gain and range scale according to depth.
It works as follows:
The range changes automatically to locate the bottom on the lower half of the screen. It
jumps to one step shallower range when bottom echoes reach a halfway point of the full scale
from top and to one step deeper range when they come to the lower edge of the scale.
The gain is automatically adjusted to display the bottom echo in reddish-brown (default color
arrangement).
Clutter level (on the main menu), which suppresses low level noise, is automatically adjusted.
2.5.2 Enabling automatic operation
Two types of automatic modes are available:AUTO1,for fishing, and AUTO2,for cruising.
Since cruising uses a higher clutter rejection setting than fishing, it is not recommended for
detection of fish because weak fish echoes may be deleted by clutter rejection. Note that the
[SHIFT] keys([+],[-]), [RANGE] switch and [GAIN] control are inoperative in the auto mode.
Press the [AUTO] key. Each press of the key turns the auto function on or off in the sequence
shown below
AUTO-1
(FISH MODE) AUTO-2
(CRUISE MODE)
AUTO OFF
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