Plastimo VHF FX-500 Mode D'emploi page 90

Sputnikovaya Sistema) satellites.
SBAS: Turns the SBAS (Satellite Based Augmentation System) fucntion ON or OFF. The SBAS transmits
signals to correct errors, and improves accuracy and reliability in data received from regular GNSS
satellites. When this function is ON, you can use the corrected data.
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