Furuno FAR-2107 Series Service Manual page 431

7.2 Antenna Unit
The figure below shows sea clutter and STC CONT voltage created by averaging the
sea clutter level. For instance, if a strong sea clutter signal ahead is erased by the manual
STC, weaker target echoes behind are also erased. If the STC is adjusted so as to leave
echoes behind, sea clutter signals ahead remain. In such a case, optimum pictures are
obtained on the whole by STC-controlling of sea clutter different by each bearing
according to each bearing.
STC Control signal
STC Control signal
STC Control signal
Time
Far
Mid
Near
Sea clutter
STC Control signal
Average of Sea clutter
STC Control signal
STC Control signal
Fig. 7.2.20 Schematic Diagram of Automatic STC Processing-2
7-26