I'm concerned that, in their quest to address the needs of the general public's radio clocks, NIST might overlook the frequency standards needs of our metrology community. (Unless the metrology community provides adequate feedback to NIST *before* it might be too late?)
According to their interpretations of ISO/IEC 17025, many customers require metrology labs to include inter-comparison procedures for assurance. For example, they might require a GPS disciplined house frequency standard to be cross-checked against another non-GPS frequency standard (for assurance purposes). In the past Loran-C served this need well as the alternate source of traceable frequency. But with the demise of Loran-C, WWVB has become more important for this purpose. Yes, we know that GPS out-performs WWVB for frequency; but within a stated uncertainty (that's adequate for many purposes), WWVB still supplies the alternate source of traceable frequency comparison. Do any of the resident gurus of this list have opinions as to whether or not NIST's proposals might exclude WWVB as a source of traceable frequency comparisons? At least, I think it prudent that some of us let NIST know that we're still relying on WWVB for traceable frequency comparison systems. Greg ----- Original Message ----- From: "beale" <[email protected]> To: <[email protected]> Sent: Monday, March 28, 2011 3:02 PM Subject: [time-nuts] improved WWVB signal being planned? I thought this was interesting... I don't know if this had been already mentioned here- probably some list members are already part of the process! I wonder if this would be a spread-spectrum code like the GPS signal? "[...] Another idea being actively investigated is to add phase modulation to the existing WWVB signal while leaving the AM BCD code intact. This would allow all existing devices to continue to work, but allow a new generation of radio-controlled clocks to be developed. These new devices would have greater processing gain and therefore be capable of reading the time code with a lower signal-to-noise ratio." from "We Help Move Time Through the Air Managers of WWVB Explore Options to Improve the Service Further" by John Lowe, manager of NIST radio stations WWV/WWVH/WWVB. http://tf.boulder.nist.gov/general/pdf/2504.pdf _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
