Re: Unclear about dgps precision?

[Gary E. Miller]

Yo M!

On Fri, 29 Mar 2024 05:38:50 +0000 (UTC)
M de Luis <gimme_the_giffs@yahoo.com> wrote:

> I think I mean 7-digits of precision, after the decimal place. 

Once again, my mind reading is weak.  A copy of what you see would
make things clear.

> Here's the gpsdebuginfo script output requested. I couldn't unlock
> the root user on my Pi, so only sudo output.

    $ sudo su -
    # gpsdebuginfo

Is that hard?

> I'm really not
> understanding the JSON position output of dspd, and why it seems so
> unexpectedly stable, given that the ublox GPS output varies randomly
> within a several metre bound. Maybe your analysis will shed some
> light.

The gpsdebuginfo tells me about your configuration, not what you see.

Samples of what you see in u-center, and some JSON, would eliminate the
beed to mind read.

To grab a JSON sample: gpspipe -w -x 10 > sample.json

From the debug output:

> gpsd: 3.22 (revision 3.22)

That is a bit old.  3.25 is latest release.  But unlikely an issue here.

> /usr/sbin/gpsd -Gn

I have no idea how your gpsd works with neither a control socket, or
serial device.  But it does appear to.

> {"class":"DEVICES","devices":[{"class":"DEVICE","path":"/dev/ttyUSB0",
> "driver":"u-blox","subtype":"SW 7.03 (45969),HW 00040007","

Could be either a u-blox 6 or 7.  Do you know which?  Neither are stable
to much better than 10 meters.

RGDS
GARY
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Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
        gem@rellim.com  Tel:+1 541 382 8588

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