Garmin GPSMAP 3205 - Manual (Page 107)

GPSMAP 3205 Owner’s Manual
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WAAS Capability
The GPSMAP 3205 is capable of receiving WAAS satellite signals. WAAS is
an FAA (Federal Aviation Administration) funded project to improve the overall
accuracy and integrity of the GPS signal for aviation use, but land and sea-based
users can also benefit from this system. There are currently two WAAS satellites
that can be received in the USA, one over the Atlantic Ocean and one over the
Pacific Ocean, in a geostationary orbit over the equator. Effective use of the
WAAS satellite signal may be limited by your geographic location in relation to
those satellites, now in developmental service. WAAS satellite signal reception
requires an absolute clear view of the sky and works best when there are no
nearby obstructions such as buildings or mountains.
WAAS satellites are numbered 33 or higher when viewing the sky view on your
GPSMAP 3205. Initial reception of the WAAS signal may take up to 15-20
minutes, then 1–2 minutes afterwards. When WAAS differential correction has
been received for GPS satellites (numbers 32 or below), a “D” appears in the
signal bar of the sky view and “Ready For Navigation with WAAS” appears in
the Status field. To learn more about the WAAS system, its satellite locations
and current state of development, visit the FAA web site ( gps.faa.gov ). Because
WAAS requires CPU resources of the GPSMAP 3205 to search for and track
the satellites, you can disable the WAAS feature to improve unit performance if
WAAS reception is not available in your area.
To disable or enable WAAS capability:
1. On the GPS tab, highlight the Setup sub tab.
2. Use the ROCKER to highlight the WAAS field, and press ENTER.
3. Highlight On or Off, and press ENTER.
Digital Selective Calling (DSC)
Digital Selective Calling (DSC) uses marine VHF radio and Global Positioning
System (GPS) technologies to transmit and receive location information. DSC is
used by mariners to assist them in two major areas: Distress Calls and Position
Reporting.
A non-emergency DSC Position Report allows mariners to exchange and display
the positions of one another. When a DSC position is received, the mariner can
choose to create a waypoint or to show the received position on an electronic
map.
An emergency DSC Distress Call allows a vessel in trouble to transmit a
substantial amount of information in a single transmission or “call,” without
the need for voice communication. When any nearby rescuer receives the DSC
signal, an alarm sounds and they immediately receive the position of the caller.
The rescuer can then choose to navigate (Go To) the callers position to assist or
forward the call on to the Coast Guard. When the Coast Guard receives the call,
they can immediately access the callers information (such as who they are and the
type of vessel) in their database while they are in transit to the callers position.
Any time a vessel receives a DSC call, they can store that location and quickly
navigate to that position using a Go To. This makes DSC a time-saver, especially
in an emergency situation. To use DSC, users must first register their VHF radio
with the FCC and receive a Maritime Mobile Service Identity (MMSI) number.