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GPS and WSJT-x decode problems #gps #rpi4b8gb #wsjt-x

 

Equipment: G90, digirig mobile, raspberry pi 4 with 8g. ?Ferrite toroid is used to block any RFI coming from the usb c cable to the Pi4. ?I¡¯m using the uBlox GPS dongle. ?The GPS connects within a few minutes. ?

the problem: ?Flrig connects to The G90. ?WSJT-x decodes fine, but the decodes are at best .5 off. ? I still get lots of qso¡¯s, but I¡¯d like it better. ?


what I¡¯ve done: ?I¡¯ve made certain the GPS works. ?The time in Conkey looks correct. ?I¡¯ve used time.is as a guide to sync the Pi4 with the terminal command to set the date and time. ? But, I¡¯m still .5 off. ?Any ideas? ?
 

Use chrony and the GPS for your time syncing.

Works for most of my needs..

Kevin? -- KD9EFV
 

that does not install.? ?any other ideas???
 

I have also installed a RTC mod and it keeps time until I turn the hotspot on and then its starts to drift.? I believe i installed the software correctly.? maybe not
 

Do you have a RTC chip/hat?
For the GPS, are you using gpsd?
For the gpsd / chrony addition, all you should need to do is :
sudo sed -i.bak 's/pool/#pool/g' /etc/chrony/chrony.conf
echo "refclock SHM 0 offset 0.5 delay 0.2 refid NMEA" | sudo tee -a "/etc/chrony/chrony.conf"
sudo systemctl restart chrony
chronyc sources -v
which should report

? .-- Source mode? '^' = server, '=' = peer, '#' = local clock.
?/ .- Source state '*' = current best, '+' = combined, '-' = not combined,
| /???????????? 'x' = may be in error, '~' = too variable, '?' = unusable.
||???????????????????????????????????????????????? .- xxxx [ yyyy ] +/- zzzz
||????? Reachability register (octal) -.?????????? |? xxxx = adjusted offset,
||????? Log2(Polling interval) --.????? |????????? |? yyyy = measured offset,
||??????????????????????????????? \???? |????????? |? zzzz = estimated error.
||???????????????????????????????? |??? |?????????? \
MS Name/IP address???????? Stratum Poll Reach LastRx Last sample
===============================================================================
#* NMEA????????????????????????? 0?? 4?? 377??? 15?? +771us[ +914us] +/-? 100ms
 

thanks, i made those changes.? I will report back in a day or so.
Doug

Virus-free.


On Mon, Mar 14, 2022 at 5:42 PM Kevin <kd9efv@...> wrote:
Do you have a RTC chip/hat?
For the GPS, are you using gpsd?
For the gpsd / chrony addition, all you should need to do is :
sudo sed -i.bak 's/pool/#pool/g' /etc/chrony/chrony.conf
echo "refclock SHM 0 offset 0.5 delay 0.2 refid NMEA" | sudo tee -a "/etc/chrony/chrony.conf"
sudo systemctl restart chrony
chronyc sources -v
which should report

? .-- Source mode? '^' = server, '=' = peer, '#' = local clock.
?/ .- Source state '*' = current best, '+' = combined, '-' = not combined,
| /???????????? 'x' = may be in error, '~' = too variable, '?' = unusable.
||???????????????????????????????????????????????? .- xxxx [ yyyy ] +/- zzzz
||????? Reachability register (octal) -.?????????? |? xxxx = adjusted offset,
||????? Log2(Polling interval) --.????? |????????? |? yyyy = measured offset,
||??????????????????????????????? \???? |????????? |? zzzz = estimated error.
||???????????????????????????????? |??? |?????????? \
MS Name/IP address???????? Stratum Poll Reach LastRx Last sample
===============================================================================
#* NMEA????????????????????????? 0?? 4?? 377??? 15?? +771us[ +914us] +/-? 100ms



--
Douglas S. Iverson
Ripon, WI 54971
920-509-4618

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