Re: Low cost GPS, minimal assembly

[Daniel O'Connor]

[ Hijacking a reply because I can't find the original message ]

> On 23 Apr 2022, at 00:23, Hal Murray <halmurray@sonic.net> wrote:
> 
> 
> gdt@lexort.com said:
>> That's funny.  I am not really clear on the details of LeoNTP, but I was
>> going to suggest that you look at it.  Perhaps you can explain why "order
>> another LeoNTP box" isn't the right answer.  I don't mean to argue with your
>> rationale, but that would be instructive as to your requirements. 
> 
> The question started over on time-nuts where the OP reported that LeoNTP is 
> unobtainium.  I took a quick look on the web and found a not-available note 
> that mentioned suply chain issues.
> 
> Steve Sommers reported that he has seen them off by several seconds.
> 
> The OP had servers available so my reaction was to get GPS into one of them.  
> Aside from replacing Leo, I wanted to know if there were any 
> no-assembly-required options available for getting GPS into a server and this 
> seems like the right group for that quesion.

If you are using it for NTP then GPS+PPS over USB is quite adequate (from 
experience).

The next level would be something where you can do an input capture on the PPS 
I don't think there are any pre canned solutions. I made one with a Beagle Bone 
Black and a uBox GPS module but it's not exactly turn key. Or for a server then 
you would need a fancy (ie $$$$) internal card.

Ian Lepore (RIP) who worked for Micro Semi and worked on FreeBSD did a bunch of 
tests on a PPS over USB setup and found it more than acceptable for keeping a 
PC in (good) time. Here's the thread: 
https://lists.freebsd.org/pipermail/freebsd-arm/2019-August/020263.html

--
Daniel O'Connor
"The nice thing about standards is that there
are so many of them to choose from."
 -- Andrew Tanenbaum