Beta (time signal)
Encyclopedia
Beta is a time signal service in the VLF
range in Russia
, operated by the Russian navy. There are 6 transmitter stations, which take turns transmitting time signals and other communications.
Although the transmitters are active 24 hours a day, each transmits the time code one hour per day.
Beginning on the hour is 25 minutes of 25.0 kHz, including morse code
station identification and time code. This is followed by 5-minute intervals of 25.1, 25.5, 23.0 and 20.5 kHz. No time code is sent during the last quarter of an hour.
The transmitters are estimated to operate at 1000 kW, achieving 30–50 kW EIRP. (The difference is due to the low efficiency of antennas at this frequency, which must be much smaller than the 12 km wavelength.)
The time code consists of a series of carrier pulses:
The hour or date is not coded.
Most of the stations were built in the 1970s. RJH63, built later, has a different transmission:
Very low frequency
225px|thumb|right|A VLF receiving antenna at [[Palmer Station]], Antarctica, operated by Stanford UniversityVery low frequency or VLF refers to radio frequencies in the range of 3 kHz to 30 kHz. Since there is not much bandwidth in this band of the radio spectrum, only the very simplest signals...
range in Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
, operated by the Russian navy. There are 6 transmitter stations, which take turns transmitting time signals and other communications.
Although the transmitters are active 24 hours a day, each transmits the time code one hour per day.
Beginning on the hour is 25 minutes of 25.0 kHz, including morse code
Morse code
Morse code is a method of transmitting textual information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment...
station identification and time code. This is followed by 5-minute intervals of 25.1, 25.5, 23.0 and 20.5 kHz. No time code is sent during the last quarter of an hour.
The Beta network
Beta consists of the following transmitters:| Callsign | Transmitter Location | 20.5 kHz | 23 kHz | 25.1 kHz | 25.5 kHz | Map Link |
|---|---|---|---|---|---|---|
| RJH69 | Vileyka VLF transmitter Vileyka VLF transmitter The "Vileyka" VLF transmitter is the site of the 43rd Communications Center of the Russian Navy , situated west of the town of Vileyka in Belarus . The "Vileyka" VLF transmitter is an important facility for transmitting orders to submarines in the very low frequency range... near Molodechno (Belarus Belarus Belarus , officially the Republic of Belarus, is a landlocked country in Eastern Europe, bordered clockwise by Russia to the northeast, Ukraine to the south, Poland to the west, and Lithuania and Latvia to the northwest. Its capital is Minsk; other major cities include Brest, Grodno , Gomel ,... ) |
x | x | x | x | 54.462356°N 26.769218°E |
| RJH77 | Archangelsk | x | x | x | x | 64.360491°N 41.568489°E |
| RJH63 | Krasnodar Krasnodar Krasnodar is a city in Southern Russia, located on the Kuban River about northeast of the Black Sea port of Novorossiysk. It is the administrative center of Krasnodar Krai . Population: -Name:... |
x | x | x | x | 45.403904°N 38.155689°E |
| RJH99 | Nizhny Novgorod Nizhny Novgorod Nizhny Novgorod , colloquially shortened to Nizhny, is, with the population of 1,250,615, the fifth largest city in Russia, ranking after Moscow, St. Petersburg, Novosibirsk, and Yekaterinburg... (former German Goliath transmitter Goliath transmitter Goliath transmitter was a VLF transmitter of the German Navy near Kalbe an der Milde in Saxony-Anhalt, Germany, which was in service from 1943 to 1945... ) |
x | x | x | x | 56.170596°N 43.940334°E |
| RJH66 | Bishkek Bishkek Bishkek , formerly Pishpek and Frunze, is the capital and the largest city of Kyrgyzstan.Bishkek is also the administrative centre of Chuy Province which surrounds the city, even though the city itself is not part of the province but rather a province-level unit of Kyrgyzstan.The name is thought to... (Kyrgyzstan Kyrgyzstan Kyrgyzstan , officially the Kyrgyz Republic is one of the world's six independent Turkic states . Located in Central Asia, landlocked and mountainous, Kyrgyzstan is bordered by Kazakhstan to the north, Uzbekistan to the west, Tajikistan to the southwest and China to the east... ) |
x | x | x | x | 43.039444°N 73.6125°E |
| RAB99 | Khabarovsk Khabarovsk Khabarovsk is the largest city and the administrative center of Khabarovsk Krai, Russia. It is located some from the Chinese border. It is the second largest city in the Russian Far East, after Vladivostok. The city became the administrative center of the Far Eastern Federal District of Russia... |
x | x | x | x | 48.48555°N 134.82333°E |
Frequency usage
The time code consists of a series of signals on multiple frequencies. Transmission starts on the hour. Each time a new frequency is selected, there is 1 minute of low power while the transmitter is adjusted, then full-power transmissions begin.The transmitters are estimated to operate at 1000 kW, achieving 30–50 kW EIRP. (The difference is due to the low efficiency of antennas at this frequency, which must be much smaller than the 12 km wavelength.)
| Frequency | Minutes | Signal | |
|---|---|---|---|
| Start | Duration | ||
| 25.0 kHz | :00 | 1 | Transmitter tune-up, low-power unmodulated carrier |
| :01 | 5 | Unmodulated carrier | |
| :06 | 1 | Morse code call sign, on-off keying | |
| :07 | 3 | Unmodulated carrier | |
| :10 | 3 | On-off modulated with 40 Hz square wave | |
| :13 | 9 | Time code, on-off modulation | |
| :22 | 3 | On-off modulated with 40 Hz square wave | |
| 25.1 kHz | :25 | 1 | Transmitter tune-up, low-power unmodulated carrier |
| :26 | 4 | Unmodulated carrier | |
| 25.5 kHz | :30 | 1 | Transmitter tune-up, low-power unmodulated carrier |
| :31 | 4 | Unmodulated carrier | |
| 23.0 kHz | :35 | 1 | Transmitter tune-up, low-power unmodulated carrier |
| :36 | 5 | Unmodulated carrier | |
| 20.5 kHz | :41 | 1 | Transmitter tune-up, low-power unmodulated carrier |
| :42 | 5 | Unmodulated carrier | |
| Off | :47 | Transmission ends |
The time code consists of a series of carrier pulses:
- Each 100 ms, a 25 ms burst of carrier is transmitted
- Each second, a 100 ms burst of carrier is transmitted
- Each 10 s, a 1 s burst of carrier is transmitted
- Each minute, a 10 s burst of carrier is transmitted
The hour or date is not coded.
Most of the stations were built in the 1970s. RJH63, built later, has a different transmission:
| Frequency | Minutes | Signal | |
|---|---|---|---|
| Start | Duration | ||
| 25.0 kHz | :00 | 1 | Transmitter tune-up, low-power unmodulated carrier |
| :01 | 5 | Unmodulated carrier | |
| :06 | 1 | Morse code call sign, on-off keying | |
| :07 | 2 | Unmodulated carrier | |
| :09 | 2 | On-off modulated with 40 Hz square wave | |
| :11 | 9 | Time code, on-off modulation | |
| 25.1 kHz | :20 | 2 | Transmitter tune-up, low-power unmodulated carrier |
| :22 | 1 | Unmodulated carrier | |
| 25.5 kHz | :23 | 1 | Transmitter tune-up, low-power unmodulated carrier |
| :24 | 2 | Unmodulated carrier | |
| 23.0 kHz | :26 | 1 | Transmitter tune-up, low-power unmodulated carrier |
| :27 | 4 | Unmodulated carrier | |
| 20.5 kHz | :31 | 1 | Transmitter tune-up, low-power unmodulated carrier |
| :32 | 4 | Unmodulated carrier | |
| :36 | 4 | Digital data, ±50 Hz frequency-shift keying Frequency-shift keying Frequency-shift keying is a frequency modulation scheme in which digital information is transmitted through discrete frequency changes of a carrier wave. The simplest FSK is binary FSK . BFSK uses a pair of discrete frequencies to transmit binary information. With this scheme, the "1" is called... , 50 baud Baud In telecommunications and electronics, baud is synonymous to symbols per second or pulses per second. It is the unit of symbol rate, also known as baud rate or modulation rate; the number of distinct symbol changes made to the transmission medium per second in a digitally modulated signal or a... |
|
| Off | :47 | Transmission ends |
Further reading
- VLF radio networks information
- The Russian VLF time-signal stations, “Beta”, by Trond Jacobsen, with detailed transmission format information.