[time-nuts] Testing 2 Cesiums & GPS

[Brooke Clarke]

Hi:

I have fired up Cesium source # 1227 (this one was shipped in a foam lined box unlike # 1013 that had metal straps holding it).  
http://www.pacificsites.com/~brooke/pdf/sn1227_CF600.pdf

I have made the following plots all on the same spreadsheet:
s/n 1013 vs. s/n 1227 offset of about -1E-10 (Dark Blue)
GPS vs. s/n 1227 offset of about -3E-12 (Violet)
GPS vs. s/n 1013 offset of about 5E-10 for a 23 minute segment (Green)

I've added a 10 MHz output to s/n 1227 and am using that for the reference input to the SR 620 counter.

So far it looks like s/n 1227 that has been in storage for 2 + years has turned on very well at -3E-12.  Maybe a tweak after a few days of data.

Something is very wrong with s/n 1013.  But the green lock light is one.
When I turn off the modulation and open the loop, sweeping the control voltage produces a definite peak.  If the true peak was outside the control voltage range how much frequency error would there be?

Have Fun,

Brooke Clarke, N6GCE

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