Furuno GP-1640F, Operator'S Manual, Page: 29 / 108

3-3
Indices and chart enlargement
When the soft key ZOOM OUT is used, you will
see several frames appear on the chart. These
frames are called indices and they show you
what parts of the chart can be enlarged in the
current picture range. The areas circumscribed
with smaller frames can be enlarged, but the
area enclosed by the largest frame cannot.
Sample chart (Japan and South Korea)
showing indices
Remarks on chart display
A chart will not be displayed in the following
conditions:
•
When the chart scale is too large or too small.
•
When scrolling the chart outside the indices.
When this happens, select proper chart scale.
Chart symbols
FURUNO mini chart card
The table below shows FURUNO mini chart
symbols and their meanings.
FURUNO chart symbols
Symbol Description
Summit
Wreck
Lighthouse
Lighted Buoy
Buoy
Radio Station
Position of Sounding
Obstruction
Fishing Reef
Platform
Anchorage