Garmin GPS II Plus - Manual (Page 90)

DGPS Interface
The last two format settings allow the differential-ready GPS II + to accept RTCM
DGPS corrections in RTCM 104 version 2.0 format. Using DGPS corrections will
improve receiver accuracy to 1-5 meters, regardless of errors induced by the gover n-
ment’s Selective Availability (SA) program. Two RTCM options are available:
RTCM/NONE (84a), which allows connection to a beacon receiver with no output
capability; and RTCM/NMEA (84b), which allows DGPS input and NMEA output.
Once a RTCM setting has been selected, the GPS II + will either automatically try
to tune the last frequency and bit rate you selected or will switch to the default fre-
quency of 304.0 kHz with a bit rate of 100 bps if no previous beacon has been
tuned. You may also enter your own frequency and bit rate if desired.
To enter a DGPS beacon frequency:
1. Highlight the ‘freq’ field, and press ENTER.
2. Enter the desired frequency, and press ENTER.
3. Highlight the ‘rate’ field, and press ENTER.
4. Select the desired transmission rate, and press ENTER.
Fig. 84a
Fig. 84b
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