Low cost receiver
Prototype
pg. 6
Low-Cost SBAS Receiver Design (SkyTraq Venus 838) - 25/02/2020
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Serial Port”.
A window should appear, in which you can set the output baudrate to 9600. Save this configuration, and then
disconnect by pressing the “Close” button again. You can then try connecting to the
SkyTraq board in the exact same
manner on the same COM port, but with a baud rate of 9600 this time. If GNSS viewer then behaves regularly, you can now
configure the other settings to suit your use case and environment.
3.5.
Enabling SBAS on the SkyTraq
To allow the SkyTraq to use the Australia and New Zealand SBAS, you
need to use the “Configure SBAS Advance” item from the “Venus 8”
Drop-down menu in GNSS Viewer.
Once you can see a form similar to the one displayed here on the left,
you should enable the SBAS system, disable Ranging, enable the
corrections, and then enable WAAS
. From there, use the “Modify
Default PRN” section to change the WAAS PRN to 122, the PRN of the
Australia and New Zealand SBAS.
You can now save the configuration.
It is also recommended to disable position pinning to allow true 1hz (or
higher) output rates, and to change the Navigation mode to suit your
use case kinematics. In our testing we have found the navigation mode
to have a significant impact on the positioning performance.
You should set the NMEA output to suit your requirements, generally
$GPGGA strings are the most useful, as they contain your location.
You can now re-connect the HC-06 Bluetooth module.
3.6.
Installing the Components into the Enclosure
At this stage you should have two functioning assemblies: the SkyTraq board with attached HC-06 Bluetooth module, and
the Adafruit PowerBoost board mounted to the 3D-printed tray with attached battery and switch. The next step is to place all
of these components into the Enclosure. Images of the complete power assembly and the compartments/through-holes for
each of the components in main enclosure are shown below:
Please note that the solder connections to the battery may be fragile; take care not to force any of the components into their
compartments, and to stop if anything feels too tight in order to avoid damage.
