RE: Help needed with USB GPS device

[Gavin Davenport]

Bug raised with Redhat for the 2 issues

> Slightly different discussion then - what's an affordable alternative
Since COVID, the price and availablility of GNSS receivers is all over
the place.  Picking the right one for you depends on how you will use it
(indoors, outdoors, fixed, mobile, etc.), what you need from it (3m, 1m,
1cm accuracy, 1ms, 1us or 1ns accuracy). and what you will connect to
(PCIe, real RS-232, fake RS-232, Raspberry Pi, etc.).

So first you need to choose your niche.
.
.
.
Let us know your requirements, then we can make timely suggestions.

I don't have a spot for an external antennae right now but I plan to have in 
the future. Right now it's sat on a windowsill.

I might be able to expose a further serial port, I'm honestly surprised that's 
still an alternative compared to USB.

My ISP is 15msec away at the moment and I'd like to have something providing 
>1msec accuracy if possible. 

I have yet to venture into the location accuracy element of it, lets assume 
it's not critical now.

Thanks for the answers so far.

I'm trying to follow this guide - 
https://gpsd.gitlab.io/gpsd/gpsd-time-service-howto.html

I'm now using this approach in chrony
refclock SHM 0 refid GPS precision 1e-1 offset 0.9999 delay 0.2
refclock SHM 1 refid PPS precision 1e-7

And chrony can see the GPS source as follows:
MS Name/IP address         Stratum Poll Reach LastRx Last sample
===============================================================================
#x GPS                           0   4   377    18   -964ms[ -964ms] +/-  200ms
#? PPS                           0   4     0     -     +0ns[   +0ns] +/-    0ns
^+ 2001:8b0:0:23::205            2   6    77    24    +23us[  +75us] +/-   19ms
^- 2001:7b8:3:2b::4              2   6    77    25  +3106us[+3158us] +/-  334ms
^- 2001:7b8:3:2b::5              2   6    77    24  +2865us[+2917us] +/-   53ms
^- 2001:418:3ff::1:53            2   6   377    21  -1315us[-1263us] +/-   96ms
^+ 2a05:b400:c::123:63           2   6   377    19   -296us[ -245us] +/- 6816us
^* 131.111.8.63                  2   6   377    18   -437us[ -386us] +/- 7137us
^+ 2a05:d01c:9d2:d200::be00:5    2   6   377    17   -370us[ -370us] +/- 5314us

x indicates a source which chronyd thinks is a falseticker

Can I do anything about this is or is this just the logical conclusion with 
this device ?

Gavom