[time-nuts] Fw: Rb Oscillator - rather fundamental question

[Magnus Danielson]

Rick Karlquist wrote:
> EWKehren at aol.com wrote:
>> The HP 5062C is not a "Primary Standard", and that is why it is called a
>> "Reference" because it uses a different transition of Cesium 133 with the
>> frequency of 9192.631,774,3 MHz which does not meet the definition of a
>> second
>>  and resulted in a relative short product life even though modified to run
>> with a  FTS tube and "Standard Frequency" makes it a grate Frequency
>> Standard.
>> Bert Kehren
> 
> I never knew that.  I stand corrected on the 5062C.

Ehm, no. This is just 4,3 Hz higher than the 0 C-field transition. It's 
not a different transition, it is the C-field shifted (0, 0) transition.

I know of no Caesium clock that uses 0 C-field applied. The C-field 
helps to spread out the 7 Rabi constellations such that the Ramsey 
features can be investigated for the (0,0) transition can be 
investigated correctly. This is a key to properly test the frequency. 
The C-field shift is compensated for as it is fairly accuratly 
predicted. The C-field is servoed by looking at the neighboring 
tranistions Rabi constellations which depends stronger on the C-field. 
This is what a "digital" Caesium does and is what is needed to become 
primary standard as it removes aging in the C-field. The systematic 
error that remains can be handled at design and trimmed in product 
development.

The 5062C is not different in this respect.

So Rick, I don't find that you stand corrected.

Cheers,
Magnus