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Re: FYI - GPS
Posted: Mon Sep 04, 2023 9:04 am
by CU7AAZ
EU1AEQ wrote: ↑Mon Sep 04, 2023 6:01 am
The link is corrupted. Are there any changes in the mod 2 file?
This should work
https://drive.google.com/file/d/1VrMJm0 ... KJqII/view
73s
Re: FYI - GPS
Posted: Thu Sep 07, 2023 3:54 pm
by SA0BUX
I bought another RT3S GPS recently, s/n: 2212R03S11012XX with TYT MCU (clone STM32) which seems to have much better GPS reception compared to my oldest RT3S ( s/n: 2202R03S11019XX ) .
I had no signals at all on the old radio inside my office but had up to 13 satellites on the new.
It even receives some additional non USA GPS satellites (could be Galileo, Glonass,BeiDou? ) so the receiver chip seems to be different than on my old radio.
Have to look into the NMEA serial output, maybe I can see what additional satellites it is receiving?
Re: FYI - GPS
Posted: Tue Sep 12, 2023 12:12 pm
by OE1MWW
SA0BUX wrote: ↑Thu Sep 07, 2023 3:54 pm
I bought another RT3S GPS recently, s/n: 2212R03S11012XX with TYT MCU (clone STM32) which seems to have much better GPS reception compared to my oldest RT3S ( s/n: 2202R03S11019XX ) .
...
following the general trend of the recent times, i also bought a second RT3S
It's serial is 2105R03s11041xx and also equiped with a 'TYT' MCU. I can confirm, this one is
much faster on GPS collection and grabs more SAT than my 'old' RT3S serial 2104R03S11018xx
Can't believe that just another MCU makes this difference.
Wolfgang
Re: FYI - GPS
Posted: Tue Sep 12, 2023 2:09 pm
by SA0BUX
OE1MWW wrote: ↑Tue Sep 12, 2023 12:12 pm
SA0BUX wrote: ↑Thu Sep 07, 2023 3:54 pm
I bought another RT3S GPS recently, s/n: 2212R03S11012XX with TYT MCU (clone STM32) which seems to have much better GPS reception compared to my oldest RT3S ( s/n: 2202R03S11019XX ) .
...
following the general trend of the recent times, i also bought a second RT3S
It's serial is 2105R03s11041xx and also equiped with a 'TYT' MCU. I can confirm, this one is
much faster on GPS collection and grabs more SAT than my 'old' RT3S serial 2104R03S11018xx
Can't believe that just another MCU makes this difference.
Wolfgang
I'm not brave enough to open and disassemble this tiny radios with SMD inside them.
Otherwise we could maybe see if they made some changes.
Personally I think they have a more modern and sensitive GPS receiver as I notice that I see different colors in the GPS status pages for the satellites.
I guess that the number under the bars is the PRN but I think they are re-used as only 01-32 is available.
Re: FYI - GPS
Posted: Tue Sep 12, 2023 2:28 pm
by F1RMB
The two colors are for GPS and BeiDou, 32 each.
Cheers.
---
Daniel
Re: FYI - GPS
Posted: Tue Sep 12, 2023 3:54 pm
by SA0BUX
F1RMB wrote: ↑Tue Sep 12, 2023 2:28 pm
The two colors are for GPS and BeiDou, 32 each.
Cheers.
---
Daniel
Ok, It could be that beidou satellites are not so much over the Nordic countries or not earlier
I seldom look on GPS details but I have a good android app for it.
Re: FYI - GPS
Posted: Tue Sep 12, 2023 3:56 pm
by F1RMB
I never received one BeiDou sat here.
Cheers.
---
Daniel
Re: FYI - GPS
Posted: Tue Sep 12, 2023 6:11 pm
by SA0BUX
F1RMB wrote: ↑Tue Sep 12, 2023 3:56 pm
I never received one BeiDou sat here.
Cheers.
---
Daniel
Is it something in the NMEA output on the radio that indicates which type of satellite it is?
I had some ideas to connect a laptop when I test and compare the satellite performance on the radios?
I have no coverage inside my apartment so I can't test there now but I plan to buy a GPS L signal distribution from SV1AFN, then I could hookup an inside antenna.
I have one outside antenna now for my Thunderbolt GPSDO which I need to split to several receiver anyway.
Re: FYI - GPS
Posted: Tue Sep 12, 2023 6:20 pm
by F1RMB
Yes, the two first letters refer to the system, GP, BD, GL, etc.
Cheers.
---
Daniel
Re: FYI - GPS
Posted: Tue Sep 12, 2023 7:47 pm
by F1RMB
SA0BUX wrote: ↑Tue Sep 12, 2023 6:11 pm
F1RMB wrote: ↑Tue Sep 12, 2023 3:56 pm
I never received one BeiDou sat here.
Cheers.
---
Daniel
Is it something in the NMEA output on the radio that indicates which type of satellite it is?
I had some ideas to connect a laptop when I test and compare the satellite performance on the radios?
I have no coverage inside my apartment so I can't test there now but I plan to buy a GPS L signal distribution from SV1AFN, then I could hookup an inside antenna.
I have one outside antenna now for my Thunderbolt GPSDO which I need to split to several receiver anyway.
Many years ago I built a GPSDO (using a Symetricom card), with a LCD display. I also built a 10MHz distribution based on the SV1AFN schematics. It worked very well (thread is on EEVBlog forum).
Cheers.
---
Daniel