Re: SparkFun GNSS L1/L5 Breakout - NEO-F10N, SMA - GPS-24114 - SparkFun Electronics

[Frank Nicholas]

Thanks for the info.  Replying for my education & knowledge of the list.

Replying inline below - hope it comes through Ok.

> On Mar 22, 2024, at 9:09 PM, Gary E. Miller <gem@rellim.com> wrote:
> 
> Yo Frank!
> 
> On Fri, 22 Mar 2024 19:10:33 -0400
> Frank Nicholas <frank@nicholasfamilycentral.com> wrote:
> 
>> Really?  I noticed the L2/L5 band difference.  And now I see the F10N
>> is missing the GLONASS constellation.  F10N claims “ meter-level
>> positional accuracy”.  M9N claims “~1.5 meter accuracy”.  
> 
> Depends on the M8 version.  Some are L1/L2 and some are L2/L5

Assuming a typo M8 vs. M9.  The Sparkfun M9 I linked is L1/L2.  The F10 I 
linked originally is L1/L5.  Generally which is better?  For timekeeping, based 
on same environment, which is better?

> The u-blox product line card has good comparisons:
> 
> https://content.u-blox.com/sites/default/files/GNSS_LineCard_UBX-13004717.pdf
> 
> To me a big problem with the M10N is the lack of native USB.  The
> native USB means you never have to worry about speed, parity, or
> overflowing the serial port.

My experience is that “native USB” still means you have to set serial port type 
parameters:  speed, parity, stop bits, etc.

In my opinion, lack of native USB is not an issue because the Sparkfun breakout 
board natively has the GPS chip serial connected to a USB chip/adapter on 
board, and a simple jumper/solder pad to change that on the breakout board for 
native serial pads.

> 
> Missing the GLONASS is a feature.  Adding NacIC is no use in the Americas.

Thanks - I suspected that it wasn’t valuable in the Americas.  :^)  “NacIC” - I 
don’t know what that term is?  

> 
> Here is the F10N data sheet:
> 
> https://content.u-blox.com/sites/default/files/documents/NEO-F10N_DataSheet_UBX-23002117.pdf
> 
> CEP(50) is 1m over 24 hours, so hat is nice.  But PPS is 30 to 60ns.
> 
> Cold start is 28 seconds.
> Max rate 10Hz.
> 
> Limited to 4G, so best used in static applications.

Static/GPS timing is my use case.  I don't know what “4G” is.

> 
> The serial port is hard wired to a USB-Serial chip.  So you have to
> mode the board to get serial.

See above for simple serial/USB/jumper pad.

> 
> The F10N is new, and new to me, and better on paper than the first M10
> parts I have looked at before.
> 
> By comparison, the M9N:
> 
> https://content.u-blox.com/sites/default/files/NEO-M9N-00B_DataSheet_UBX-19014285.pdf
> 
> Same:
> 
> It is the same in PPS and the 4g.

For me, I don’t know what “4g” is.

> 
> Better:
> 
> It can cold start in 24 seconds, not a big win over 28.  And max rate of
> 25Hz, a win over 10, but I think the rate are interpolated numbers.
> 
> Has USB and serial ports.  Can take RTM3.3
> 
> A few added firmware features.
> 
> Worse:
> 
> CEP(50) of 2m, so that is worse.
> 
> In summary:
> 
> The big win is the M9N can take RTCM3.3 and has the USB.
> 
>> For USA use (mainly timekeeping), do those make it 2/3 as good?  I’m
>> not questioning your knowledge/statement, I'm just trying to
>> understand/learn.
> 
> For timing, looks like a toss up.
> 
>> BTW - for almost 1/2 the price for 2/3 as good, maybe it’s still a
>> better deal, depending on needs?
> 
> For timing, the F10N is a win at any price.  

Thanks - that’s my use case, and why I originally asked/wrote what I did.  :^)

> 
> If one needs high data rate, or RTCM then the M9N is the win at any price.
> 
> RGDS
> GARY
> ---------------------------------------------------------------------------
> Gary E. Miller Rellim 109 NW Wilmington Ave., Suite E, Bend, OR 97703
>       gem@rellim.com  Tel:+1 541 382 8588
> 
>           Veritas liberabit vos. -- Quid est veritas?
>    "If you can't measure it, you can't improve it." - Lord Kelvin