PTB’s Time and Frequency Services 2017

PTB’s time services accessible to the common public comprise the operation of Network Time Protocol (NTP) servers, a telephone time service and the standard frequency and time dissemination by the low frequency transmitter DCF77. New achievements in such services have been gained by improving the timing infrastructure for connecting external facilities to the local reference time scale, PTB’s realization of Coordinated Universal Time, UTC(PTB). A new NTP server setup including smart meter-gateway administrator servers has been installed. Monitoring of signals from the long wave time service from the Europaische Funkrundsteuerung GmbH (EFR) and of Galileo timing signals has been included in the routine operations. PTB, like other national metrology institutes (NMI), publishes regular reports on measurement results of GPS time derived from the satellite signals compared to the local reference time scale based on well calibrated receivers. These reports give confidence that the broadcast GPS signals provide a good approximation to UTC in both frequency and time. Accreditation bodies usually require accredited calibration laboratories to subscribe to the GPS monitoring reports from their NMI as part of the process of demonstrating traceability. The content and format of PTB’s Time Service Bulletin has been revised and extended accordingly. It contains now not only the differences “GPS time – UTC(PTB)” but also “Galileo System Time (GST) – UTC(PTB)” and “GST – GPS time”, as reported in Galileo navigation messages. On initiative of Deutsche Telekom Technik (DTAG), PTB continues to support the operation of fiber optic time transfer of UTC(PTB) (one pulse-per-second) and frequency (10 MHz) signals to a test center of DTAG in Bremen. In early 2018, the link will be extended to the DTAG main timing facilities in Frankfurt am Main. All these activities result in a broader availability of German legal time. Furthermore, PTB organized and participated in GPS equipment calibration exercises, to support BIPM in the framework of the generation of Coordinated Universal Time (UTC).