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    Re: Timekeeping in the post-WWV/post-HF world
    From: Ian Vaughn
    Date: 2018 Sep 27, 17:47 -0700

    Along the same lines as the post looking at the precision of a $6 wristwatch, here's some detailed test results comparing a high-end quartz oscillator with microsemi's shiny new CSACs:

    https://web.whoi.edu/obslab/wp-content/uploads/sites/98/2017/10/Clocks-and-Timing-VerificationLEGAL.pdf

    Having only casually worked with the CSACs, I'd solidly recommend the $6 wristwatch.  Keeping CSACs cared for, fed (with power) and disciplined (correcting the static drift via constant comparison to a high-end GPS) is far more work than the $5000 per module pricetag suggests.  Even then, word on the street is that Microsemi is having major quality control issues after acquiring Symmetricon.  For a while Microsemi wouldn't even sell clock modules under warranty.

    Meanwhile, my $15 wristwatch ($6 in 1982) has drifted all of "one horizon uncertainty" in the last two months with exactly no effort.  Regular checks would reduce the error far lower.

    --Ian

       
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