Fig. 3-9 Split Frequency Feature - Raymarine L750 Operating Handbook

Chapter 3: Operating Instructions
50 kHz frequency
When using this frequency, the transducer can scan a wide area.
The 50 kHz signal penetrates water well, so it is good for use in
deep water.
200 kHz frequency
When using this frequency, the transducer scans a narrower area,
but produces a more detailed view. The 200 kHz frequency is good
for seeing fish which are near the bottom or are close together. The
200 kHz setting is better for use in very shallow water.
"Dual" frequency
These settings use both the 50 kHz and 200 kHz signals at the
same time. This allows for some of the advantages of both
frequencies. The dual settings produce good depth penetration
and good detail in the display. Using the "Dual 50 kHz" setting, the
display is produced using the signal from the 50 kHz beam, with
additional information from the 200 kHz beam. Using the "Dual 200
kHz" setting, the display is produced using the signal from the 200
kHz beam, with additional information from the 50 kHz beam.

Fig. 3-9 Split Frequency Feature

Display
from 200 kHz
beam
Display
from 50 kHz
beam
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