System information

Hemisphere GPS Using PocketMax3 p/n 874-0012-000 Page 12 of 32
2. Differential Source
The box at the bottom of the screen labeled Diff Mode within the GPS menu button, in the
Position tab is where you can change differential sources. The other place you can change the
differential mode is in the menu for the differential source (either SBAS/BEAC/LBAND), in the
Status tab. In either of these, you can switch between SBAS (WAAS/EGNOS) and Beacon (or
OmniSTAR if applicable) just by tapping the circle beside the desired differential source. By
switching the differential source, the menu along the bottom of the screen will automatically
update to reflect the current configuration.
2.1.1 SBAS Menu
The Status tab provides details of the satellites being used for SBAS corrections. The PRN
(satellite ID number), longitude, elevation and azimuth, and the bit error rate of the tracked
satellites are displayed. The SBAS Bit Error Rate (BER) shows the quality of the SBAS data
received from the satellite(s). BER values should stay below 150 to maintain differential lock.
Ideally, this value will remain between 0 and 50.
The line graph displays the BER’s for up to three SBAS satellites, however only one satellite is
required to provide corrections.
Figure 2-1 SBAS Status Screen
2.1.2 BEAC Menu
The tabs within the beacon menu button are Status and Tune. The Status tab provides details of
the beacon station providing corrections, including the name (if available), the frequency and the