Questions and feedback #2

What is the baud rate of the data connection between base and rover Alpha?
I am trying to get radio modems between them for it. Can it be adjustable like 9600 or 33600 for many std device? For use with Lora slower but more secure link, gsm phones etc.

What are the hardware specifications. Especially modem-rover data connection. 3.3V TTL serial data, max 3.3V in/out ? 115200 baud 8 N 1?
5V ok? other? Any manual?
Is the hardware directly a chip like https://www.skytraq.com.tw/homesite/S1216F8-RTK_v2.pdf
And messages etc. are from it?

in my rtkviewer version update tells it can not find update server to update rtkviewer.
I updated it manually from a link here, which is ok for me. ( polaris-gnss.com/rtkviewer.zip 1 or something)
( I tested even via VPN to be in Taiwan, all firewall was down etc. Can I try it otherway like ftp, ping it if I know the address…)?

I could not get firmware check by rtkviewer.exe by going into 9600 speed. It just wont connect then. (win 10 PC) I don’t need it yet. I tried to check if I has latest firmware. I am doing R&D to get this RTK going here.

-I am now buying now rf-link for base-rover Alpha data ports. Takes some time to find operational pair.
I don’t now its baud speed? Has anyone any idea?
( Problems to find flexible and good small standalone 868MHZ Lora or standard device and meet the regulations ) 868 and 434 are used for car keys here with 10mW and 1W could block 1 km radius.

I can not find any instructions to use polaris-gnss.com server for NTRIP server. Or if it is available with fixed ip?
I found an blog of floating server but I did not study it, yet.

-I hope I do not need PC as a NTRIP server but only data link bw base and rover stations.
I hope to build an permanent 1-2 km base station with a battery + solar cells on the field where there are 30 m ‘hills’ in the way. to start with.

-Do you have an idea what is the source of EMI disturbing antenna? Alpha, wires, Power pack? I could build some emi shielding then, metal mesh or lates, ferrites, emi capacitor to power wires etc. My intention is to build up a standalone base station and rover. With antenna.

3.3V UART connection is 115200 8N1. 5V level for UART not OK. User Guide section 3-2, 3-3 has I/O interface descriptions. There is a photo image in this thread on radio connections: how connect Base to Rover with UART telemetry

The UART interface pins goes through an FPGA to S1216F8-RTK UART. Under control of a microcontroller detecting push button for TTL UART / USB / Bluetooth interface selection, the FPGA routes S1216F8-RTK UART to different interfaces.

No new firmware update yet, not to worry.

Other answers replied in this thread: connect server

Your application should be #4 application figure, no NTRIP needed: https://www.polaris-gnss.com/blog/user-guide-now-available

There is a cycle-slip field in RTK Viwer. If there is interference affecting RTK operation, but not sufficiently large to lower signal level as easy to identify indicator, there will be some constant high number count showing in this field. Occasional cycle slip value of 1 ~ 3 is OK.

how far telemetry radio can reach? from base to rover sending correction

How far telemetry radio can reach depends on radio transmission power. Typically the distance is far less than possible using NTRIP Internet connection, which could be 30Km ~ over 60Km, depending on ionospheric activity level.

Can i use the alpha+ Without the aide of internet???. My field of application is more on remote area, no network available…

Please see if this helps:


i see but 2hrs is very long for land survey on 1 a point.

what i want is Base and Rover communicating thru Telemetry Radio and Data collection on my smartphone

i have read Bluetooth on alpha+ will be dissable if telematry radio is installed and we have to add bluetooth module…

What can you say? is it posible? pls help me so that i can build my first RTK

If your Alpha+ is purchased recently, then Bluetooth will not be disabled when using TTL/UART connecting with radio. One could easily check by (1) know how it behaves when using Bluetooth mode with Lefebure NTRIP Client, status will go from No Data to Invalid:0 (2) If clicking the select switch changing to TTL/UART mode, if connecting again with Lefebure NTRIP Client and seeing status going from No Data to Invalid:0, then you have the newer Alpha+ that doesn’t turn off Bluetooth in TTL/UART mode.