MTD (

Swedish Swedish or ' may refer to: Anything from or related to Sweden, a country in Northern Europe. Or, specifically: * Swedish language, a North Germanic language spoken primarily in Sweden and Finland ** Swedish alphabet, the official alphabet used by ...

abbreviation for ''Mobiltelefonisystem D'', or ''Mobile telephony system D'') was a manual

mobile phone A mobile phone, cellular phone, cell phone, cellphone, handphone, hand phone or pocket phone, sometimes shortened to simply mobile, cell, or just phone, is a portable telephone that can make and receive telephone call, calls over a radio freq ...

system for the 450 MHz

frequency band A frequency band is an interval (mathematics), interval in the frequency domain, delimited by a lower frequency and an upper frequency. The term may refer to a radio band or an interval of some other spectrum. The frequency range of a system is ...

. It was introduced in 1971 in Sweden, and lasted until 1987, when it was made obsolete by the

NMT NMT may refer to: Science and technology * Nordic Mobile Telephone, an analogue mobile phone system * Neurologic Music Therapy * Neural machine translation * Network management protocols, in the CANopen#Network management (NMT) protocols, CANopen ...

automatic service. The MTD network had 20,000 users at its peak, with 700 people employed as phone operators. MTD was also implemented in

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of Denmark , establishe ...

and in

Norway Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and t ...

(from 1976), which allowed roaming within the Scandinavian countries.

MTA

In Sweden, the first mobile phone system was MTA (for ''Mobiltelefonisystem A''), which was introduced in 1956, and lasted until 1967. It was a 160 MHz system available in Stockholm and Gothenburg, with 125 total subscribers. The second system, MTB (for ''Mobiltelefonisystem B''), had

transistor upright=1.4, gate (G), body (B), source (S) and drain (D) terminals. The gate is separated from the body by an insulating layer (pink). A transistor is a semiconductor device used to Electronic amplifier, amplify or electronic switch, switch ...

ized mobile sets, was introduced in 1962, and lasted until 1983. It operated in the 76–77.5 and 81–82.5 MHz bands, was also available in

Malmö Malmö (, ; da, Malmø ) is the largest city in the Swedish county (län) of Scania (Skåne). It is the third-largest city in Sweden, after Stockholm and Gothenburg, and the sixth-largest city in the Nordic region, with a municipal popula ...

, and had around 600 subscribers.

OLT

In Norway, the first mobile phone system was OLT, introduced in 1966. In 1976, the OLT system was extended to include

UHF Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter (on ...

bands, incorporating MTD, and allowing international roaming within Sweden.

External links

Brief description of MTD as well as MTA and MTB

Some history behind MTA and MTB (latest snapshot at the Internet Archive)
* {{DEFAULTSORT:Mtd (Mobile Network) Mobile radio telephone systems