Total Access Communication System
Encyclopedia
Total Access Communication System (TACS) and ETACS are mostly-obsolete variants of AMPS
which were used in some Europe
an countries (including the UK
& Ireland
in 1983). TACS was also used in Japan
under the name Japanese Total Access Communication (JTAC). It was also used in Hong Kong. ETACS was an extended version of TACS with more channels.
TACS and ETACS are now obsolete in Europe, having been replaced by the GSM system. In the United Kingdom, the last ETACS service operated by Vodafone
was discontinued on 31 May 2001, after sixteen years of service. The competing service in the UK operated by Cellnet (latterly BTCellnet) was closed on Sunday 1st October 2000.
Eircell (now Vodafone Ireland
) closed its TACS network on 26 January 2001. This followed a long period during which customers were encouraged to switch to GSM services. When the network was closed, there were very few, if any, active TACS customers left. Customers who switched network were able to keep their phone number, but the (088) prefix was changed to either 087 (Eircell) GSM or 086 (Esat Digifone, now O2 Ireland) GSM. At the time, full mobile number portability was not available to TACS customers and the (088) prefix was closed. An automatic voice message was left in place for 12 months advising callers of the customer's new prefix.
ETACS is however still in use in a handful of countries elsewhere in the world. NMT
is another analog cellular standard that was widely used in Europe, mainly in the Nordic countries, which has now been fully replaced by GSM except for limited use in rural areas due to its superior range.
TACS BAND Summary
Advanced Mobile Phone System
Advanced Mobile Phone System was an analog mobile phone system standard developed by Bell Labs, and officially introduced in the Americas in 1983, Israel in 1986, and Australia in 1987. It was the primary analog mobile phone system in North America through the 1980s and into the 2000s...
which were used in some Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
an countries (including the UK
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
& Ireland
Republic of Ireland
Ireland , described as the Republic of Ireland , is a sovereign state in Europe occupying approximately five-sixths of the island of the same name. Its capital is Dublin. Ireland, which had a population of 4.58 million in 2011, is a constitutional republic governed as a parliamentary democracy,...
in 1983). TACS was also used in Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
under the name Japanese Total Access Communication (JTAC). It was also used in Hong Kong. ETACS was an extended version of TACS with more channels.
TACS and ETACS are now obsolete in Europe, having been replaced by the GSM system. In the United Kingdom, the last ETACS service operated by Vodafone
Vodafone
Vodafone Group Plc is a global telecommunications company headquartered in London, United Kingdom. It is the world's largest mobile telecommunications company measured by revenues and the world's second-largest measured by subscribers , with around 341 million proportionate subscribers as of...
was discontinued on 31 May 2001, after sixteen years of service. The competing service in the UK operated by Cellnet (latterly BTCellnet) was closed on Sunday 1st October 2000.
Eircell (now Vodafone Ireland
Vodafone Ireland
Vodafone Ireland Limited, part of the Vodafone Group, is the largest mobile phone company in Ireland in terms of active subscribers, and was previously called Eircell. The mobile phone system in use is a digital GSM 900 system, and also a third-generation UMTS system...
) closed its TACS network on 26 January 2001. This followed a long period during which customers were encouraged to switch to GSM services. When the network was closed, there were very few, if any, active TACS customers left. Customers who switched network were able to keep their phone number, but the (088) prefix was changed to either 087 (Eircell) GSM or 086 (Esat Digifone, now O2 Ireland) GSM. At the time, full mobile number portability was not available to TACS customers and the (088) prefix was closed. An automatic voice message was left in place for 12 months advising callers of the customer's new prefix.
ETACS is however still in use in a handful of countries elsewhere in the world. NMT
Nordic Mobile Telephone
NMT is the first fully automatic cellular phone system...
is another analog cellular standard that was widely used in Europe, mainly in the Nordic countries, which has now been fully replaced by GSM except for limited use in rural areas due to its superior range.
Frequency bands used by ETACS in the UK
| Channel | Cell TX (MHz) | Mobile TX (MHz) | Notes .............. |
|---|---|---|---|
| 1 | 935.0125 | 890.0125 | 25 kHz spaced channels |
| 23 | 935.5625 | 890.5625 | 1st of 21 dedicated vodafone control channels |
| 24 | 935.5650 | 890.5650 | 2nd of 21 dedicated vodafone control channels |
| 300 | 942.4875 | 898.0625 | 9.5 kHz peak speech fm deviation |
| 323 | 943.0625 | 898.0625 | 1st of 21 dedicated cellnet control channels |
| 600 | 949.9875 | 904.9875 | last TACS channel, ETACS extended this to 1320 later |
| 0 | |||
TACS BAND Summary
| Base TX Start | End (MHz) | Mobile start | End (MHz) | BAND |
|---|---|---|---|---|
| 935 | 950 | 890 | 905 | TACS 600 Channels |
| 935 | 960 | 890 | 915 | TACS 1000 Channels |
| 917 | 950 | 872 | 905 | E-TACS 1320 Channels |
UK ETACS and USA AMPS compared
| Feature | TACS | AMPS | Notes .............. |
|---|---|---|---|
| Channel Spacing | 25 kHz | 30 kHz | |
| Speech peak Freq Dev | 9.5 kHz | 12 kHz | |
| Signalling FSK peak Freq Dev | 6.4 kHz | 8 kHz | |
| Signalling rate | 8 kbit/s | 10 kbit/s | |
| SAT 0 | 5970 Hz | 5970 Hz | |
| SAT 1 | 6000 Hz | 6000 Hz | |
| SAT 2 | 6030 Hz | 6030 Hz | |
| ST | 8000 Hz | ||
| Mobile TX pwr MAC 0 | 2.82 W | ||
| Mobile TX pwr MAC 1 | 1.12 W | ||
| Mobile TX pwr MAC 2 | 447 mW | ||
| Mobile TX pwr MAC 3 | 178 mW | ||
| Mobile TX pwr MAC 4 | 70.8 mW | ||
| Mobile TX pwr MAC 5 | 28.2 mW | ||
| Mobile TX pwr MAC 6 | 11.2 mW | ||
| Mobile TX pwr MAC 7 | 4.5 mW | ||