Garmin GPSMAP 278 User Manual

Page 96

To restart the scan:

1. Press

MENU.

2. Highlight

Restart Scan, and press ENTER.

To manually enter a frequency and bit rate:

1. With the unit set to

Garmin DGPS or RTCM In/NMEA Out,

highlight the

Beacon field, and press ENTER.

2. Highlight

User, and press ENTER.

3. Highlight the

Frequency or Bit Rate field, and press ENTER

4. Enter a frequency or bit rate. Press

ENTER when finished

When the unit is receiving a DGPS signal, the Signal to Noise Ratio)

(SNR) and Distance fields show data. The SNR range is 0 dB to 30

dB, with 30 being the best. The Distance field may or may not show

data, depending on the signal being broadcast from the DGPS site.
The DGPS beacon transmitters are operated by the United States

Coast Guard (or similar government agency in other countries),

which is responsible for their accuracy and maintenance. For DGPS

transmitter problems or to find the most updated list of frequencies

and coverage areas, contact your local USCG or see their Web site at

Advanced NMEA Output Setup

If you are going to interface the GPSMAP 278 with another piece

of equipment (such as a radar or autopilot), you must set the

unit to output NMEA data. The NMEA data transmission can be

customized to keep the output rate at two seconds. If too many

NMEA sentences are activated, the unit may take longer than two

seconds to update.
You can also set the Output Rate to Fast to output a minimum

number of NMEA sentences at one-second intervals.

To access the Advanced NMEA Output Setup:

1. Highlight the

Setup tab on the Main Menu.

2. Select the

COM 1 or COM 2 sub tab.

3. Highlight the

Serial Data Format field, and press ENTER.

4. Select

NMEA In/NMEA Out, and press ENTER.

GPSMAP 278 Owner’s Manual

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