[time-nuts] Lab Test Equipment

Peter Vince pvince at theiet.org
Tue Jul 20 17:58:44 UTC 2010


Hello, and welcome to the group, and what I find an endlessly
fascinating subject.

Said's suggestion of using a 'scope is fine, but is mind-numbingly
tedious (I've done it!)  I think you need a frequency counter/timer
whose readings can be output to a computer for subsequent analysis.
There are lots to choose from, but I use some old HP (now Agilent)
53131 and 53132 counters.  These have a very simple serial port that
spits out the data for easy reading by any terminal emulator program.
You can then go away and leave the system logging the results, and
come back days or weeks later to analyse it.  Analysis is a big
subject, and pretty much the gold standard is Bill Wriley's "Stable32"
(http://www.wriley.com/)

I don't think you need NIST calibrated equipment.  Even if you had
something, it would drift eventually - and likely quite soon for
measuring rubidiums.  Far better, I believe, to get yourself a GPS
disciplined oscillator.  Short term, its timing will be a bit noisy,
but long term it is locked to the ultimate references.  Many in this
group have a Trimble Thunderbolt which are readily available on ebay.
See, for example, ebay item number 290308733659, which is a complete
kit of Thunderbolt, power supply, and antenna, being sold by Bob Mokia
(ebay seller "fluke.l") - another time-nut in China.

     Peter


On 20 July 2010 05:54, Heathkid <heathkid at heathkid.com> wrote:
> Hello.  I'm new to this list but have 3 Rb standards and am looking at
> measuring time (or drift between them).  What is the most important piece of
> NIST calibrated test equipment I need to own?  Is 3 enough using two Rb
> standards as a reference/control group (considering the 3rd can vote before
> being exposed to experiments)?
>
> Thanks...



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