Fishfinder 340C Owner’s Manual 29U SING THE FISHFINDER 340C > U SING THE MAIN MENU• Scale—controls the depth scale displayed vertically alongthe right side of the graph. The settings are Overlay(default), in the Corners, Basic scale, or No Scale.• Custom Range—allows you to specify a custom viewingrange or scale. When On, this range appears as Custom inthe Range setting. The left value is the top of the scale andthe right value is the bottom of the scale.• Color Scheme—sets the colors for the Sonar and FlasherPages. The default is Classic White.• Temperature and Water Speed—hides or displaystemperature and water speed on the Sonar Page. When set toAuto, the Fishfinder automatically displays this information,only if it is received from the transducer.Sonar TabThe Sonar tab enables you to set up initial settings and calibrations.The following settings are available:• Auto Gain—controls the aggressiveness of the Auto Gainwhen the Gain option is set to Auto (see page 37). Thehigher the setting, the greater the number of targets appearon the screen. The lower the setting, the less clutter on thescreen. The settings are Low, Medium (default), and High.• Auto Color Gain—controls what colors are applied to theobjects on the screen when the Color Gain option is setto Auto (see page 37). Color DCG is based on depth andmakes it easier to spot subtle changes in bottom conditionsor fish sizes. DynaColor™ (default) represents the latest