1. OPERATION
7
1.7
Adjusting the Gain
The gain may be adjusted automatically
(Fishing or Cruising) or manually. In automat-
ic operation, the gain is automatically adjust-
ed to display the bottom echo in reddish
brown. If you need to lower the gain in auto-
matic operation, use the gain offset feature.
For manual adjustment, see paragraph 1.7.2.
The Gain Area setting on the Sounder menu
determines how gain is adjusted. For setting
details, see Gain Area on page 22.
The “Normal” setting is the conventional gain
adjustment method; the gain setting affects
only current echoes.
The “All” setting applies gain to both current
and past echoes.
1.7.1
Selecting gain adjust-
ment method
1.
Press the
GAIN-H
(for HF) or
GAIN-L
(for
LF) control to open the Auto Gain setting
window.
2.
Use
S
or
T
to select Fishing, Cruising or
Off as appropriate.
Fishing:
This mode clearly displays
weaker echoes and is for searching fish
schools. "H (L):AF" is shown at the top left
corner on the screen.
Crusing:
This mode clearly displays
stronger echoes (for example, bottom)
and suppresses weak echoes. Use it for
general cruising. "H (L):AC" is shown at
the top left corner on the screen.
Off:
Select to manually adjust gain.
3.
For automatic operation (Fishing or Cruis-
ing), use the auto gain offset (range: -5 to
+5) with
W
or
X
.
4.
Press the
ENTER
key.
1.7.2
Manual gain adjustment
The
GAIN HF
and
GAIN LF
controls adjust
the sensitivity of the receiver. The setting
range is 0.0 to 10, and the current setting is
shown at the top of the screen as H (or L) +
XX (setting value).
Generally, use a higher setting for deep wa-
ters and a lower setting for shallow waters. In
any case, adjust the controls so that a slight
amount of noise remains on the screen.
Note:
This function is inoperative if Gain/
Mode on the Navnet menu is set for NavNet.
See 1.20.6 for details.
GAIN: 0
GAIN: 4
Gain Area setting: "Normal"
Gain Area setting: "All"
GAIN: 0
GAIN: 4
CAUTION
Adjust the gain properly. Incorrect gain may
give wrong depth indication, which could
result in grounding if the vessel is steered
according to the depth indication.
Gain too high
Gain proper
Gain too low
