Care to tell us more about your clock accumulator, Bill?
DaveB, NZ
- Original Message -
From: "Bill Hawkins" <[EMAIL PROTECTED]>
To: "Discussion of precise time and frequency measurement"
Sent: Wednesday, February 08, 2006 4:49 PM
Subject: Re: [time-nuts] Seco
> I've noticed that the emphasis on this list seems to be placed on
> fast measurements of short-term drift. I'm more interested in long
> term drift, so I use a clock accumulator to measure drift over
> months (no setup has lasted a year, yet).
>
> Why is the focus on short-term drift?
>
> Bill
I've noticed that the emphasis on this list seems to be placed on
fast measurements of short-term drift. I'm more interested in long
term drift, so I use a clock accumulator to measure drift over
months (no setup has lasted a year, yet).
Why is the focus on short-term drift?
Bill Hawkins
__
Brooke,
Let me clarify this a bit more.
> It's my understanding the a properly working Cs standard probably has it's
> frequency slightly off from perfect, but does NOT have any drift in
> frequency.
Agreed. Over a month there should be no obvious
frequency drift in a Cs standard. However, from
Brooke,
Correct, with a Cs standard you can expect that there
will be no long-term drift in frequency. However if you
look at the short-term you will often see trends that
look like drift. In your S/N 1227 plot both red and blue
show trends on the order of 3 to 4 days. You are wise
not to call thi
Hi Tom:
The plot with red and blue is the old data on s/n 1227 where the red
points are from LORAN-C and the blue points from GPS.
s/n 1227 = http://www.pacificsites.com/~brooke/pdf/Cs_Drift0429.pdf
from April 29, 2005.
This might be a clue to the problem I'm now having with s/n 1013.
http://w
Brooke,
> For the last couple of weeks it has shown a parabolic plot like s/n
> 1227, although this time the polarity is opposite that of s/n 1227 which
> also showed drift, but that may be a setup difference. A plot of s/n
> 1227 is at: file:///C:/Webdocs/pdf/Cs_Drift0429.pdf
This plot has
Brooke,
> For most of the test the SR620 was using it's internal oscillator and
> just recently I changed it to the PRS10 external standard but that does
> not seem to have made any difference.
Correct. Since your time interval values are on the
order of 1 microsecond or less the accuracy of th
Hi John:
No, the plots are of the raw data. Comparing this morning (8:27) @ 892
ns with yesterday morning (8:27) @ 858.2 gives a linear slope of 3.7E-13.
This may be the Ultra Stable Oscillator, but I don't see how changing
the C-field would effect it. That is, if the C-field is changed then
Hi Brooke --
Did you remove any linear offset before generating thorse plots? They
sure look a lot more like an Xtal aging with offset removed, than a Cs.
I wonder if it might be related to your use of the 1MHz output, rather
than 1pps, to drive the stop input. Maybe you're slipping cycles du
Hi:
Sorry for the bad links, here are good ones:
Today's plot = http://www.pacificsites.com/~brooke/pdf/sn1013_850_Drift2.pdf
s/n 1227 29 Apr 2005 plot =
http://www.pacificsites.com/~brooke/pdf/Cs_Drift0429.pdf
Brooke
Brooke Clarke wrote:
>Hi:
>
>A year ago I took apart the FTS4060 that was DO
Hi:
A year ago I took apart the FTS4060 that was DOA (s/n 1013) because of
rough shipping and used it to figure out most of the interconnect
wiring. A few months ago I put it back together with the thought of
selling it as a parts unit. But first powered it up and found that it
now locked an
12 matches
Mail list logo
