[time-nuts] Cesium DOES Drift, not

Poul-Henning Kamp phk at phk.freebsd.dk
Wed Apr 20 14:48:21 EDT 2005


In message <MGEKKFGEAIKJOOPJPGIKKEEAFEAA.richard at karlquist.com>, "Richard \(Ric
k\) Karlquist \(N6RK\)" writes:
>My understanding from talking to the experts is
>that no aging, or environmental effects are observable
>on the 5071A, and measurements have been made into
>the 10^-15 range.  Also, no systematic frequency offset
>has been observed down to at least 1x10^-14.  IE,
>frequency offset between different 5071A's is randomly
>distributed with a mean within 10-14 of laboratory
>standards, such as Cs fountains.  Knowing the way we
>overdesigned the 5071A, I am not surprised that it
>is this good.

I think the confusion here is that drift was measured and reported
on the HP5061.  But that the drift did not originate in cesium bits
of it, but rather in the electronics and magnetic shielding if I
remember right.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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