How to manually adjust the gain of the fish finder？

Under normal circumstances, it is recommended to manually adjust the gain from high to low, and gradually adjust the fishfinder screen until the noise just disappears and the screen is clean, but the target still exists. This is an amateur gain adjustment method.

So how to professionally use manual gain mode for optimal gain adjustment?

Step 1: First, turn off the automatic range of the fish finder;

Step 2: Adjust the manual range to the display range of about 2 times the water depth of the bottom

Step 3: Look at the screen to adjust the gain, so that the bottom of the sonar screen just vaguely appears at the position of the second false seabed shape.

(The reason for the formation of this second false bottom is that the sonar signal emitted by your fish finder is reflected after hitting the bottom, and the echo signal that is not reflected back to the probe due to terrain refraction is reflected again to the bottom after reaching the water surface, and then passes through. Secondary reflections from the seafloor are picked up by the probe.)

Step 4: Re-adjust the range to the depth of the water layer you need to pay attention to, or turn on the automatic range.

Every time you change the position of the fishing point, you need to perform manual gain adjustment according to the above steps. Because optimal gain is affected by the following environmental factors:

• water depth

• Water temperature and water density

• Water clarity

• salinity

Ship speed (low ship speed, the gain can be smaller; high ship speed, the gain needs to be relatively increased - usually it is recommended to use the automatic gain mode)