Garmin GPSMAP 235 Sounder - Manual (Page 52)

42
GETTING START-
ED
Using the GOTO
Key
Selecting Map Scales
The map display has 16 available range scales from 1/8th to 4096 nautical miles
(1/4 to 7500 kilometers). The map scale is controlled by the I and H keys,
with the current scale displayed at the bottom of the data window.
To select a map scale:
1. Press H to zoom out and I to zoom in.
The sounder has a built-in worldwide database to 64 (32 in U.S.) nautical miles
(see Appendix D for a built-in coverage map), with more detailed coverage avail-
able through the use of G-chart
TM data cartridges (see pages 84-85 for installing
and using G-chart TM cartridges). The sounder will display cartography as long as
there is chart information available for the range you’ve selected. Map coverage
will conform to the following conditions:
• When the selected zoom range is covered by either the internal database or
a G-chart data cartridge, cartography will be displayed.
• When the selected zoom range is covered by both the internal database and
a G-chart cartridge, cartography will be displayed using the data with the
best resolution.
• When the selected zoom range exceeds the resolution of the chart in use by
up to two settings, overzoom cartography will be displayed. The display
will not show any filled landmass areas, and an ‘Ovr Zm’ warning will
appear in the scale field. The lat/lon grid will also be turned on regardless
of the map configuration setting.
• When the selected zoom range exceeds the resolution of the chart in use by
more than two settings, all cartography will be replaced by a track plot dis-
play, and a ‘No Map’ warning will appear in the scale field. The lat/lon grid
will be displayed regardless of the map configuration setting. Additional
caution should be used while navigating in track plot mode.
SECTION
4
MAP PAGE
Map Scales
A B
A. Whenever the selected map scale exceeds the reso-
lution of the chart by up to two settings, an ‘Ovr
Zm’ warning will appear in the scale field.
B. Whenever the selected map scale exceeds the reso-
lution of the chart by more than two settings, a ‘No
Map’ warning will appear in the scale field.
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