[time-nuts] GPS Week 1536 causing problems?

[Magnus Danielson]

M. Warner Losh wrote:
> In message: <4A52BD4F.5020000 at rubidium.dyndns.org>
>             Magnus Danielson <magnus at rubidium.dyndns.org> writes:
> : Hal Murray wrote:
> : >>>> Anyone else lose an 18x?
> : > 
> : >>> I lost one a while ago.  Similar.  It just stopped doing anything
> : >>> useful.
> : > 
> : >> Battery failure?
> : > 
> : > I don't think it has a battery inside.  That seems like a poor design.  Too 
> : > many reasonable use cases would include sitting in a drawer for extended 
> : > periods of time.
> : 
> : Providing an RTC has benefits, especially when considering week-rollover 
> : issues, since when the receiver wakes up it has no idea of date at all, 
> : pulling in the RTC time and date is a sufficient hint, and adjusting 
> : with detailed info from the GPS is a trivial extention. Then adjusting 
> : the RTC is not a hard thing to do every once in a while. The same 
> : problem could also be solved using EEPROM space. A byte would suffice.
> 
> Usually, you're right.  There's one case that might make it not
> suitable.
> 
> Many contracts require spares for all the important gear.  Long
> storage times makes storing the last known date ineffective.  Of
> course in this case "long" is on the order of 9-odd years.  This may
> be good for many applications, but not necessarily ones that have 10
> or 15 year deep spares requirements...

I agree that they are not suitable for that type of application. 
However, it does not make the battery unsuitable for GPSes as such, 
which was the point I was trying to make. How and if this detail springs 
to mind for any particular vendor is the issue. A flakey RTC may be more 
of a problem than a live one or a dead one.

Cheers,
Magnus