With the end of the speaking clock operated by Orange on July the 1st 2022, the alternative means to get the French legal time are presented below.
National References of Time
In the frame of the national network of French metrology coordinated by LNE, LNE-SYRTE is the national metrology institute for time and frequency. By decree No. 2017-292 of 06 March 2017, Observatoire de Paris is responsible for establishing the French legal time. RNT service (Service des références nationales de temps) of LNE-SYRTE department of Observatoire de Paris is in charge of these missions. It generates the reference time scale for France, UTC (OP), which is the basis of French legal time. It provides the international connection to Coordinated Universal Time (UTC) established by the BIPM (Bureau international des poids et mesures) in the framework defined by the General Conference of Weights and Measures and the Treaty of the meter convention. The RNT service provides access to these references to institutional and industrial users and throughout French society.
These activities are based on the continuous operation of about 100 instruments such as commercial atomic clocks (3 cesium clocks 5071A and 4 active hydrogen masers: 2 Kvarz CH1-75A and 2 Vremya VCH-1003M), two redundant clock comparison systems, two types of time transfer systems, using GPS (Global Positionning System) common view technique (we have about 6 different GPS recievers of different manufacturers) and using TWSTFT (Two Way Satellite Time And Frequency Transfer) technique, for national and international comparisons.
- SYRTE H Maser ensemble in the clock room
- The RNT time service
Current french and UTC times [...]
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About the end of the speaking clock
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RNT DATA
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Software for UTC(OP) comparisons
A software tool for the comparison of distant time scales has been recently developed and is now released as open source. When used with the appropriate harwdare this software allows the traceablity to UTC(OP) that is the physical realization of the legal time in France.
Software Sources in tar format
Software Sources in zip format -
UTC(OP), the basis of French legal time
UTC(OP) is the real time realization of UTC in France generated at Observatoire de Paris (OP). This timescale is at the basis of legal time disseminated in France, after adding 1 or 2 hours depending on summer or winter time. It is also the pivot for French contributions to international timescales (commercial clocks, primary frequency standards) calculated by the BIPM. UTC(OP) has been significantly improved recently. Its operation is based on the output signal of a hydrogen maser (...)
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Some definitions on national and international time references:
BIPM : Bureau Internationnal des Poids et Mesures ; this is BIPM time department that is in charge of the calculation of the international time references (EAL, TAI, UTC, UTCr, the SI second) EAL : Echelle Atomique Libre ; it is the first step of the calculation of UTC. This is performed at the end of each month using the clock data collected during the previous month. This step consists in computing a weighted average of the commercial clock data transmitted to the BIPM (about 400 clocks (...)
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Heure d’été, heure d’hiver, saut de seconde dans UTC(OP), différences TAI-UTC
HEURE D’ETE et HEURE D’HIVER
Passage à l’heure d’été : https://www.service-public.fr/particuliers/actualites/A15539
Rappel : En mars 2019, les eurodéputés ont voté pour la suppression du changement d’heure saisonnier. La décision doit être validée par chaque état membre de l’UE pour savoir s’ils conservent l’heure d’été ou l’heure d’hiver toute l’année. Dans tous les cas, le changement d’heure été et hiver 2023 est conservé. EXTRAITS de la directive 2000/84/CE du Parlement Européen et du Conseil du 19 janvier (...) -
L’horloge parlante de l’Observatoire de Paris.
Pendant près de 90 ans, l’horloge parlante a permis de mettre à disposition du grand public l’heure légale française générée à l’Observatoire de Paris. Ce service a pris fin au 1er juillet 2022. La première horloge parlante au monde
Au début des années 30, les demandes d’heure à l’Observatoire par téléphone sont si nombreuses qu’elles deviennent gênantes pour les relations téléphoniques normales d’autant plus que l’Observatoire ne dispose que d’une seule ligne: celle du directeur.
Ernest Esclangon, Directeur (...) -
Provision of the legal time by ALS162 signal
The time signal generated by the Allouis transmitter ALS162 (162 kHz), formerly France-Inter long waves, is one of the means of making legal time available in metropolitan France. This signal is used by many users (transport, energy, telecommunications, local authorities, individuals, etc ...) to synchronize more than 200,000 clocks.
Following the end of the broadcast of radio programs by Radio France in late December 2016, the ANFR (Agence Nationale des Fréquences) was commissioned by the (...) -
Diffusion de l’heure par internet - NTP: Network Time Protocol
Le LNE-SYRTE, en collaboration avec le Service Informatique de l’Observatoire, a mis en place un ensemble de serveurs pour diffuser l’heure sur Internet en utilisant le protocole NTP (Network Time Protocol).
Le protocole utilisé est Network Time Protocol (NTP) décrit dans le RFC1305. C’est un protocole sophistiqué permettant la synchronisation permanente ou non avec plusieurs serveurs avec correction des délais de transmission.
Le protocole est organisé de façon arborescente: les serveurs de (...) -
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