[LEAPSECS] it's WP7A week in Geneva

[Poul-Henning Kamp]

In message <20091004141116.GL90759 at davros.org>, "Clive D.W. Feather" writes:

>Poul-Henning Kamp said:

>> Using a GPS-UTC delta from memory, before we have an updated value

>> from the sats is just plain old bogusly wrong.

>

>Disagree.

>

>I've got a GPS receiver here. It reports UTC so, I presume, uses a stored

>delta until it picks up a new one. For the uses I have for it, an error of

>1 or even 5 seconds (but not 30) is far more useful than "no data".


In all likelyhood, it stores the almanac in a cmos-ram chip that also
contains a RTC clock.

And if so, fine, it can do the right thing.

The problem is where you don't have that possibility, for instance if
the GPS is mast-mounted (temperature would kill the batteries, and
replacement would be a PITA), or as Warner has had to deal with:
spare-parts sitting on a shelf for 5 years before they are used (by
that time your Almanac is expired many times over).

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