Re: RTK Express bluetooth to PC (and no S/V issues)

Kits
1

Hi there,

First post - be gentle! I recently purchased a RTK Express kit, upgraded to new firmware and done some test logging over some sites (trig pillars in the UK) to check accuracy with PPP post processing.

One issue I had was when starting up the satellites were zero, and a vertical fill like bar (see attached image). I changed SD cards, powered off and on numerous times, then just went through all the modes (rover/base/bubble and so on) until it decided to reset and sort itself out. Can anyone explain why this is happening and how to get around it quicker?

For serial output I used a USB C to USB C cable to my laptop from the Ublox port and can read the NMEA fine as a COM port at 9600. However, when I use bluetooth I get a virtual COM port and when connected (using PuTTY) get a semi garbled message (looks like a binary packet, then the ASCII NMEA). Is there any way I can resolve this so that I can use the bluetooth connection on a PC?

Connecting to my phone using SW maps and the bluetooth connection is fine…

The only other issue I have is when PPP processing using the TOP106 antenna. Most online services have a pull down menu where you select what antenna you have (and this one is not on the list). I also note, that some services comment that there is no antenna info within the RINEX data itself. Is there a way to add this info into a file header or similar?

Any help would be much appreciated.

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2

Just to update on the above. Having converted UBX logged data to RINEX using rtkconv, I get the attached messages when trying to upload the renamed .obs file to Trimble Centerpoint RTX processing. There must be a way to inject this info into a file header?

It seems it is dooable, as this thread implies it has been done with Ublox receiver:

https://gpsd.gitlab.io/gpsd/ppp-howto.html

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3

I think I have answered one of my own questions. I had the default set as ‘Logging Defaults’ from the wireless web interface (5 x NMEA + 2 RAW). Once I set it up as ‘Surveying Defaults’ (5 x NMEA) all was OK over the Bluetooth.

Update - U-Center windows flash on and off, so guess it is still not doable over Bluetooth? Tried at baud 9600, and 115200 and both seem OK in PuTTY.

4

Using new U-Centre 2 and the Bluetooth connection seems ok with autobauding on…