Configuring the Uplink and Down Settings

You can configure different settings for uplink and down soundings.

Before you begin

The sensor is connected to Mosa2.

About this task

Remember: Always click Apply after you change a setting and make sure there is a green check mark .

Procedure

Click the tab Trawl Explorer.

Uplink

Procedure

From TE Uplink Frequency, enter a frequency for the signal toward the vessel.
Important: This parameter must be the same in the sensor settings in Scala2.

Down Sounding

Procedure

  1. For Door Sounder with target strength only: in NBTE Setup Options you can select Down 1 + Down 2 if you want to compare two different settings on the down sounding (for example, two ping lengths or 2 frequencies). The sensor will send two consecutive pings toward down direction.
  2. From Down Sounding Range, select the range according to how many meters you want to see under the sensor.
    Note: Range influences the display of echogram images. The smaller the range, the shorter the listening time and the better the quality of images. But if you set a bigger range, data arrives slower which results in poorer image quality.
    Note: Door Sounder with target strength calibration: The range of the down sounding can automatically change to 20 meters if the distance to the bottom becomes lower than 20 meters and if you entered a trawl opening lower than 20 m. See next step to activate or not this feature.
    Important: This parameter must be the same in the sensor settings in Scala2.
  3. Door Sounder with target strength calibration: From Trawl Opening, enter 0. The opening needs to be lower than 20 m to have the autorange feature. Otherwise this setting is not useful for a door sensor.
    Important: If you use Down 1 + Down 2 sounding mode, enter 20 m or more to deactivate the autorange feature because it creates wrong data on the echogram.
  4. From Ping Down Length, enter a pulse length. Choose a pulse length according to the distance at which you need to detect the bottom. (the longer the pulse, the further you can see, but with a lower resolution):
    • Detection between 20 cm and 2 m: enter 0.1 ms
    • Detection between 50 cm and 160 m (V2: up to 80 m): enter 0.4 ms .
    Note: The maximum detection depth depends on ping frequency and type of bottom. The lower the ping frequency is, the longer the detection depth is.
  5. From Ping Down Frequency, enter a frequency for the down sounding. Make sure to put a minimum distance of 20 kHz between starboard and clump frequencies.
    Important: Frequency needs to be between 120-210 kHz for a Door Sounder.
    Important: Do not change ping frequency on a V3 sensor or it will have to be returned to a Marport sales' office for target strength calibration.

Target Strength

Procedure

From Down TVG Mode, select the appropriate TVG (Time Variable Gain) mode. See About Time Variable Gain for more information.
TVG parameters for Door Sounder with target strength calibration:
Select 20 log to see the bottom in the same color, whatever its distance from the sensor.
TVG parameters for Door Sounder V1:
  • From TVG Coefficient, enter 0.500 to see the bottom in the same color, whatever its distance from the sensor.
  • From Attenuator Coefficient, enter 25.
  • Leave VCO Coefficient default settings at 3.