[time-nuts] Frequency processing scheme of HP5065 vapour rubidium standard

[Magnus Danielson]

From: "Poul-Henning Kamp" <phk at phk.freebsd.dk>
Subject: Re: [time-nuts] Frequency processing scheme of HP5065 vapour rubidium standard
Date: Mon, 06 Nov 2006 13:21:50 +0000
Message-ID: <4604.1162819310 at critter.freebsd.dk>

> In message <000001c701a5$5f076420$0202fea9 at athlon>, "Ulrich Bangert" writes:
> 
> 
> >But what surprises us completely is the fact that different physics
> >packages need DIFFERENT thumbwheel settings to generate the SAME time
> >scale as seen with the two devices available.
> 
> This is because rubidium vapour standards are not primary standards.
> 
> They don't have a "correct" frequency, only a very stable frequency.
> 
> The actual resonance frequency of a rubidium standard depends amongst
> other things on the partial pressures inside the physics package.

Other issues includes the exact frequency pulling of the cavity wall, cavity
tuning and the mixture of buffert gas which to some degree compensates the
wall pulling.

Cheers,
Magnus