Raymarine GPS Plotter, Owner'S Handbook Manual

Page: 90 / 131

Chapter 4: Setting Up the GPS Plotter 4-13
Beacon Frequency
Both the menu item and associated soft keys show the currently used
differential beacon’s frequency in kHz.
In
AUTO
mode, this is the frequency received from the beacon receiver
and the soft keys are disabled and grayed out.
In
MAN
mode, this frequency is the user selected value which is sent via
SeaTalk/NMEA to the beacon receiver.
➤
To set a new beacon frequency manually:
Press the
SET BEACON FREQUENCY
soft key arrows to increment or
decrement the frequency in 0.5kHz steps.
The frequency range available is 287.5kHz to 325.0kHz.
Bit Rate
Both the menu item and associated soft keys show the currently used
differential beacon’s bit rate in bps.
In
AUTO
mode, this is the value received from the beacon receiver and the
soft keys are disabled and grayed out.
In
MAN
mode, this is the user selected bit rate which is sent to the beacon
receiver.
➤
To set a new bit rate manually:
Press the BIT RATE soft key repeatedly to toggle between the options
50bps, 100bps and 200bps.
Signal Strength and Signal to Noise Ratio
These items indicate the received signal strength and Signal to Noise
Ratio (SNR) in dB, received from the beacon receiver. If the display unit
is using RTCM data received via NMEA, this information is not available
and the item shows dashes, one per character.
The received Signal Strength and SNR are interrelated. SNR provides a
measure of the quality of the received signal and is dependent upon signal
strength.
Differential Age
Differential Age indicates the time elapsed since the last differential
beacon correction update.
Restart GPS
This soft key enables re-acquisition of a GPS position fix. The GPS
receiver performs a cold start.
81171_4.BOOK Page 13 Thursday, November 29, 2001 11:34 AM