3 ms·

It's a pain to get the top of second calibrated on a ceasium beam clock.

• nullc 5y ago
  Who doesn't like taking a road trip to Boulder Colorado? :) The 5071a even has internal batteries.
  • schoen 5y ago
    I know the NIST Time and Frequency division is based there, but what would you do in person once you got there? Do they have a service of some kind to help synchronize things in person for visitors?
    • deleted 5y ago
      [deleted]
    • nullc 5y ago
      Prior to the widespread use two way satellite time transfer (and secondarily GPS) for this purpose ( https://www.microsemi.com/document-portal/doc_view/133433-working-application-of-twstt-for-high-precision-remote-synchronization https://www.microsemi.com/document-portal/doc_view/133433-wo... )-- taking an atomic clock on a road trip was the standard way to obtain the second: https://ntrs.nasa.gov/api/citations/19820012622/downloads/19820012622.pdf https://ntrs.nasa.gov/api/citations/19820012622/downloads/19... There were even more portable units built specifically for this time transfer purpose. I don't think NIST has a regular service for this anymore, but since they do offer a host of calibration and verification services, I'd be surprised if you couldn't road trip a clock to obtain the second... at least for a price. I've seen some publications on transportable optical clocks in recent years, which I assume are motivated by validating newer higher precision TWSTT and fiber time transfer techniques.
      • schoen 5y ago
        Wow, that's amazing! Thanks.