Humminbird 400TX Operation Manual page 32

Transducer. The Transducer Option controls the 400TXs ability to
determine the transducer connected. If you are using the standard
tri-beam transducer or wide side transducer, no adjustment to this
menu is needed unless the transducer develops a fault, which is a
rare occurrence. The factory setting for the Transducer menu is
"Auto". The transducer menu selections will be remembered when
the 400TX is turned off.
If a faulty transducer is connected, the 400TX may not change the
screen presentation to match the transducer. In this instance, you may need to manually select
"Tri-beam" for the tribeam transducer or "Side" for the WideSide transducer.
Often a transducer switch is used to connect two tri-beam transducers, or a tri-beam and a wide
side to the 400TX. In "Auto" the 400TX identifies the transducer as the switch is changed. Only if
the transducer is faulty do you need to manually identify the transducer in the menu.
When using a dual beam (DHS-W) and tri-beam transducer together with a switch, leave the
menu set to Tri-beam. When using a dual beam and Wide Side transducer together with a switch,
manually select the correct transducer in the menu each time the switch is changed.
Display Speed. Display Speed controls the rate at which the
graphic information moves across the display. There are 5
possible speeds; the fastest rate (5) is the factory setting. If your
boat is stationary or moving very slowly for extended periods, it
may be desirable to update the display at a slower rate. The
closer the update rate matches boat speed, the more accurate is
the graphic depiction of the terrain beneath your boat.
Use the UP and DOWN ARROWS to select the desired update
rate. (1) is the slowest, (5) is the fastest. Use the MENU button to
advance to the next menu.
The Display Speed setting is remembered when the unit is powered off.
Bottom Black. There are two selections available: Off and On.
The factory setting is Off. With this setting, the 400TX displays
the bottom using 4 level grayscale. This allows you to determine
the texture and relative hardness of the bottom. Selecting Bottom
Black "ON" causes the unit to blacken in the display below the
bottom. This gives the user easiest recognition of the bottom
location, even from a great distance.
The 400TX remembers the Bottom Black setting when powered off.