Time and Frequency Standards Services
Standards of time and frequency are disseminated to New Zealand users by various means including time pips broadcast on Radio New Zealand, a talking clock service, and through monitoring TV line 6 signals.
Time "PIPS"
The most widely used time signals are those broadcast by Radio New Zealand on the National Radio station. These are derived from the MSL caesium clocks and are transmitted every hour. They consist of six "pips" of 1000 Hz tone, at one second intervals, the beginning of each pip marking the exact second. When a pip marks the exact hour, its length is doubled. When a leap second is inserted seven pips are broadcast.
Talking Clock
MSL operates a talking clock that is available to the New Zealand public via the Telecom NZ 0900 service. On dialing 0900 45-678, the user receives a voice announcement of the time followed by three "pips" of 1000 Hz tone. The start of the third pip is the exact time. The announcement and pips are repeated at 10 second intervals to give six time announcements in all, ensuring that the full minute is always included.
One of the aims of this service is to provide a means of disseminating the time standard to enable traceable calibration of stopwatches and other clocks. To perform such a calibration, it is necessary to document in a laboratory notebook, at least two calls to the talking clock and note any changes in the two times. With a modern crystal controlled timepiece, there should not be any difference in the readings unless the time interval between the calls is several days.
NTP Server
A Network Time Protocol (NTP) stratum 1 server is available for connections within New Zealand. NTP is a standard internet protocol for the synchronisation of computer time. NTP is designed mainly for synchronising high end servers but a simpler version (called Simple Network Time Protocol or SNTP) is supported by the MSL server and can be used for standalone computers. The server is referenced to UTC(MSL) by direct connection of a pulse per second signal from the master caesium clock. Further details on using the server can be found here.
TV Line 6 Signals
The horizontal synchronisation pulses transmitted on the TV signals transmitted on the TV1 and TV2 channels are controlled by rubidium oscillators. We monitor the time of arrival of these pulses at MSL and publish a weekly and a monthly bulletin containing these readings. Owners of oscillators with a stability of greater than 1 part in 109 can also monitor the arrival time of the pulses at their location and then from the bulletins calculate the offset in frequency between their local oscillator and the master clock at MSL.