Write Piaware SD card image to your microSD card.
The Piaware SD card image has both the dump1090-fa and dump978-fa pre-installed. By default, the dump978-fa is disabled and only dump1090-fa is active.
The Piaware SD card image can be easily configured by user as follows:
Option -1 (default): only dump1090-fa is running and dump 978-fa is disabled. Only one dongle is required (for 1090)
Option-2: both the dump1090-fa and dump978-fa are enabled. Two dongles, one for 1090 and other for 978 are required.
Option-3: only dump978-fa is running and dump1090 is disabled. Only one dongle is required (for 978).
Please see following post for detailed instructions: