[LEAPSECS] Leap seconds have a larger context than POSIX

Steve Allen sla at ucolick.org
Thu Feb 6 02:45:02 EST 2020


In the late 1960s German radio station DCF77 did not broadcast time
signals 24 hours a day.  Different agencies controlled different
signals at different times of day.

Deutsches Hydrographisches Institut broadcast signals based on
old UTC using their measurements of UT2 and the BIH offsets.

PTB broadcast signals of stepped atomic time based on cesium
seconds that became the SI second.

On Wed 2020-02-05T17:59:31+0000 Michael Deckers hath writ:
>The law on legal units in West Germany, from 1969-07-02, lists under
>the title "tasks of the Physikalisch-Technische Bundesanstalt"
>that the PTB has to publicize the procedures by which units without
>material prototype are realized, including the units of time and
>time scales, as well as the temperature unit and temperature scales.
>  hat die Verfahren bekanntzumachen, nach denen nicht verkörperte
>  Einheiten, einschließlich der Zeiteinheiten und der Zeitskalen
>  sowie der Temperatureinheit und Temperaturskalen, dargestellt
>  werden,")
>This can be taken to imply the task to disseminate a standard
>frequency (which they already did). But in my opinion it does not
>imply that UTC must have the same rate as the atomic time scales
>at the time -- the law even allows for several time scales.

What this means is that DHI was out of the legal time business, and
only PTB got to say what legal time was in Germany.  The head of PTB
said only SI seconds.

--
Steve Allen                    <sla at ucolick.org>              WGS-84 (GPS)
UCO/Lick Observatory--ISB 260  Natural Sciences II, Room 165  Lat  +36.99855
1156 High Street               Voice: +1 831 459 3046         Lng -122.06015
Santa Cruz, CA 95064           https://www.ucolick.org/~sla/  Hgt +250 m


More information about the LEAPSECS mailing list