The material shown below was mostly prepared around 2003 – 2008 and is now well out of date. We are in the process of repairing the dead links.
Many stations, including WWV, WWVB and WWVH, are still operational and provide high quality time information 24/7 if you need it. WWVH is easy to receive in Australia at night. Full information is at the NIST Radio Stations web site.
For a full worldwide overview see the excellent Time Signal Stations Frequency List by Nick VK2DX in Sydney.
Please also note the paragraph on the history of the Australian Time and Frequency Standard Station VNG that operated from 1964 – 2002.
Short Wave radio – traditionally our timing “workhorse”
Short Wave Radio Standard Time signals have long been a favourite tool for scientific workers and observers at field sites, where medium accuracy time is needed, to be recorded continuously. At times of good radio propagation, any simple radio with a SW band can be used to pick up a usable signal. In addition to time pips, the SW signal usually also gives voice or coded time (Hour and Minute) information and station ID. The most suitable source of standard time signals in the South Pacific is WWVH, broadcasting from Hawaii.
An interesting issue is the ‘as received’ accuracy of time signals, far away from their transmitter site. For example, the WWVH signal from Hawaii may arrive in Australia with a propagation delay of the order of 0.05 second (approx. 50 ms). When VNG was still operating, you could ‘just’ hear this difference between the local VNG pips and the Hawaiian WWVH pips by running two receivers.
VNG (Australia) died on 31 December 2002 at 23:43:43 UTCVNG was inaugurated by the Australian Post Office on 21 September 1964 at Lyndhurst, Victoria, and operated on 4.500, 7.500 and 12.000 MHz until 1 October 1987, when transmissions were terminated. There is a classic video (copied from film!) on YouTube here.
It was then moved to Llandilo, New South Wales, where the first transmission took place in June 1988. The service from Llandilo continued until 31 December 2002. In the last period of operation, standard time signals were available on 5.000, 8.638, 12.984 or 16.000 MHz (daytime only) short wave. A full description of the later Station, its history and details of broadcast codes and format can be found in the National Standards Commission information leaflet “Radio VNG”
If you would like to hear the last minute of VNG transmission on 12.984 MHz, please check with the webmaster of this site and we’ll send you an MP3 file this MP3 sound file. The last second marker was at 23:43:43 UTC
When VNG was still available, the receiving equipment could be any cheap old analogue (second hand shop) battery operated portable. Since the closure of VNG on 31 December 2002, the SW time signals available in the South Pacific have to travel from Hawaii, mainland USA, Canada or China. The received signal strength in New Zealand and Australia is lower and more variable than that from VNG, making reliable reception more difficult. In good conditions, however, the WWVH signal strength can still be remarkably good for a few hours. To improve the performance of your receiver, it is worth experimenting with long and short extension aerials. Try different antenna compass orientations, and stay away from power and cable TV cables and electric fences, all known sources of noise and interference. Short Wave radio can still be a useful, adequate, low cost entry point into fairly respectable timing.
WWVH (Hawaii) and WWV (Colorado)
WWVH and WWV broadcast on the international time standard frequencies of 2.5, 5, 10, 15 and 20 (WWV only) MHz. In New Zealand and Australia 5 and 10 are the best at night, 10 and 15 (on rare occasions also 20 MHz) in the daytime and early evening. Mostly, WWVH is received at the best signal strength, with WWV faintly in the background, but at times WWV is almost as good. WWVH is a extremely reliable and respected service. The Hawaiian service started in 1948 and between 2000 and 2007 a full set of new technology fibreglass encased antennas was built on Kauai, suggesting that the service is to continue for the coming years.
(Currently, in 2002, there appears to be a severe interference problem in Western Australia with many Indonesian fishing vessels using 10 MHz as their communication channel, ignoring international regulations. This “chatter” is noticeable as far as South Eastern Australia, but WWVH is mostly still “usable” there.)
On WWVH and WWV the seconds pulses are heard every second except on the 29th and 59th seconds of each minute. The first pulse of each hour is a long 800 ms pulse of 1500 Hz. The first pulse of each minute is a long 800 ms pulse of 1000 Hz at WWV and 1200 Hz at WWVH. The remaining seconds pulses are very short audio bursts (5 ms pulses of 1000 Hz at WWV and 1200 Hz at WWVH) that sound like the ‘ticking’ of a clock
The voice time announcements (female for WWVH, male for WWV) are just before each minute, other space and earth weather information, geophysical alerts and GPS satellite status reports are broadcast at set times. For timekeeping ignore the ongoing continuous tones on WWV/WWVH which are often heard from second 1 (i.e. the tones start one second after the full minute) until second 45. The complete format descriptions of the WWVH and WWV time codes can be found at the NIST web site.
|*** WARNING *** Can you sometimes hear confusing ‘double’ or ‘twin’ second markers ?
Do these occur during the minutes 25 – 29 and 55 – 59 ?
For example, on WWVH, do you hear: – – – – – tick pip – – – – – tick pip – – – – – tick pip – – ?
This is caused by the Chinese BPM ‘UT1’ time pips – Check ThisBecause the signals from WWVH and WWV are often weak, there is a likelihood of interference from other standard time stations on the same international frequencies of 5, 10 and 15 MHz. Most of these are no problem, because they also transmit UTC and are usually much weaker. One of these is standard time station ‘BPM’ in Pucheng, China, which is operated by the Chinese National Time Service Center (NTSC) (Shaanxi Astronomical Observatory, Chinese Academy of Sciences). Like other standard time signal stations, most of the time BPM transmits UTC.However, during the minutes 25 – 29 and 55 – 59, station BPM transmits UT1. This is a complex issue, because the difference (DUT1) between UT and UT1 can be positive or negative, and can be up to 0.9 sec. As a result, the BPM UT1 ‘pips’ can be before or after the WWVH UTC ‘tics’. If you encounter this problem with these two stations, then luckily they can be separated because the WWVH and WWVH second markers are ‘ticks’, and the BPM pips are ‘beeps’. At present (January 2009) DUT1 is about 0.4 seconds. Check the NIST web site and Nick’s list for up to date information. The identity of station BPM can be confirmed by listening during the last minute of the hour, just before the full hour, when a female (Chinese) voice speaks the words: “B P M ,….. B P M ,….. B P M ,…..”. And, to confirm this further, the ‘double’ pips should disappear on the half or full hour. Repeat: this paragraph only applies to the UT1 pulses during minutes 25 – 29 and 55 – 59.To overcome this problem, try one of the other WWV(H) frequencies.
CHU (Ottawa, Canada)
At times, on the ‘non-standard’ frequencies of 3.300, 7.850 and 14.670 MHz, Canadian Standard Time Signal Station ‘CHU’ can also be received for a few hours in the South Pacific. NOTE: 7.850 MHz is a new frequency that is being used as of January 1, 2009. The old frequency of 7.335 Mhz was within the expanded 40 metre international broadcast band (7.200 – 7.350 MHz) as decided by the International Telecommunication Union (ITU) in 2007. Indeed 7.850 has been heard in South-Eastern Australia in early January 2009, but it is found that WWVH on 5.000 is stronger at those times.
On CHU the 29th and 51st to 59th Second Markers are omitted, and alternating bilingual voice announcements of local time (not UTC) are made between seconds 50 and 59. There are further complex time codes built into this signal between seconds 31 and 90 – for details see the Klaus Betke site. However, we find that: if CHU is present, WWVH or WWV are most likely stronger, and preferred for their easier to read time code system. Also Hawaii (the source of WWVH) is closer to New Zealand and Australia than Ottawa, so that there is less propagation delay.
Do not use time pips on major international SW broadcast stations (e.g. the BBC)
Do not rely on time signals on large international SW broadcast stations (e.g. the BBC, RN, DW), which broadcast time pips on the full hour. The problem is that these SW (HF) broadcast programmes are distributed around the world using extremely long paths and variable networks that often include satellite links which add very large delays. As received, they can be significantly delayed. An exception is Radio New Zealand International (RNZI), as this only has one local transmitter. The signal from RNZI would therefore be similar to that from the regular domestic NZ broadcast.