Ping Speed; Downscan Options - Lowrance Mark-4 Operation Manual

Custom Range — Upper and Lower Limits
Used to select the upper limit and lower limit of
a section of the water column. That allows you to
view a section of the water column that does not
include the water surface.
Upper and lower limits must be at least 6.5 ft (2m)
apart.
NOTE: When using a custom range,
you may not receive any digital depth
readings, or you may receive incorrect
depth information.
DownScan Operation | Elite series
Frequency
Controls the transducer frequency
used by the unit. 800 kHz offers the
best resolution, while 455 kHz has greater depth
penetration.

Ping Speed

Controls the rate the transducer uses to send sonar
waves into the water. Ping speed adjustments can
help reduce interference from other transducers.

Downscan options

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