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Since the version 2.3 TeenAstro supports a GNSS module. In this document you will find some
important recommandation to add a GNSS module to your TeenAstro Main Unit.

Feature description

When a tiny satellite icon appears on the SHC screen, it means that the TeenAstro,
GNSS module is tracking the satellites. When satellites are tracked, you can update the latitude,
the longitude, the elevation and the time with the GNSS signal. So you don't have to key in the value.
After you get the location and Time from the GNSS, you have to resync your mount
on a Star or the Home position.

About GNSS (from wikipedia)

satellite navigation or satnav system is a system that uses satellites to provide
autonomous geo-spatial positioning. It allows small 
electronic receivers to determine their location
(
longitudelatitude, and altitude/elevation) to high precision (within a few metres) using time signals
transmitted along a line of sight by radio from satellites. The system can be used for providing position,
navigation or for tracking the position of something fitted with a receiver. The signals also allow
the electronic receiver to calculate the current local time to high precision,
which allows time synchronisation. Satnav systems operate independently of any telephonic
or internet reception, though these technologies can enhance the usefulness
of the positioning information generated.

GNSS limitations

The GNSS signal is provided by the satellites,
to get a good signal you need to be outdoor and you need a good antenna.

Arduino GNSS module for TeenAstro

The baud rate between TeenAstro and the GNSS module is 9600.
Be careful to connect the GNSS Module correctly.
VCC on VCC, GND on GND, RX on TX, TX on RX, PPS on PPS

There are 2 way to connect TeenAstro to a GNSS module, from the most preferred to the less preferred


Add an external Antenna with 5V GND RX TX interface

  • The GNSS board is inside the external GNSS Antenna
  • 4 pin or 5 pin connector must be added to the front or back panel

 

Recommended external antenna with integrated GNSS board (option 1)

The Mini 7M GPS Module are the best for the money.


Add a board inside the main unit and use an external antenna 

  • The GNSS board is connected with the VCC GND RX TX interface
  • The extern antenna is connected to the extern antenna interface
  • You have to a interface to the front or back panel


Recommended GNSS Board (option 2)

The Ublox Neo-7m are the best for the money.
If you have no experience with GNSS module, please buy a board with an USB interface.
With the USB interface, it is very easy to connect the board with the u-center utility from U-Blox.
The U-center utility will help you to check that you get satellite signal and a valid position.

 

GNSS Board mini (option 3)

If you have already used this modules you can buy a mini GNSS board without USB.
You have to check that you have the right connectors.