rtc test 2
joshua.clayton at uniwest.com
Wed Nov 18 11:03:43 PST 2015
On Wednesday, November 18, 2015 10:40:53 AM Alan Miller wrote:
> With 2 points we can generate a time per setting slope (like shown).
> This graph point is 3 seconds out of 172800 or .000174 sec/sec. That’s
> get us to within 4 minutes in a year so a longer test may be needed and a
> better setting passed on with an upgrade. Not sure about the math you have
> Josh – to get parts per billion, billion should be in the denominator.
Hah. You almost got me there. Made my head spin a little.
To convert from seconds per second to parts per billion, the numerator gets multiplied by a billion.
(technically the denominator gets multiplied too, but the billion is folded into the unit),
i.e. the billion in the denominator is implicit.
> Best accuracy to graph with would use the min & max settings for 2 points
> like below – we now have 1. Maybe the slope is negative but would still
> work if our min/max adjustments can over/under compensate.
We actually do have a second and third data point:
the first test with Adams calculated guess
the test with the maximum adjustsment
I will dig out the emails with those results when I have time,
and when I have recovered some from the math fatigue :)
hopefully they are linear.
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