Manual Tone Shift (MTS) was one of the earliest mobile telephone protocols. It was the mobile equivalent of direct-dial land telephone service. In the mobile telephone, a rotary dial toggled a flip-flop which switched a 600/1500Hz oscillator so that the pulses could be transmitted over the audio channel. This halved the baud rate, thus increasing reliability over the noise and interference-prone radiotelephone channels. 0G refers to pre-cellular mobile telephony technology. ... Push-To-Talk, commonly abbreviated as PTT, is a method of conversing on half-duplex communication lines, including two-way radio, by pushing a button in order to send, allowing voice communication to be transmitted from you, and releasing to let voice communication be received. ... The Improved Mobile Telephone Service (IMTS) is a pre-cellular VHF/UHF radio system that links to the PSTN. IMTS had originally only sixteen channels and were prone to network congestion and interference by others keying up their radios while a converstaion was already occurring on a channel. ... The abbreviated mental test score (AMTS) was introduced by Hodkinson in 1972 to rapidly assess elderly patients for the possibility of dementia. ... Autotel (also called PALM, or Public Automated Land Mobile) is a radiotelephone service which was the missing link between earlier MTS/IMTS and later cellular telephone services. ... ARP (Autoradiopuhelin, Car Radio Phone in English) was the first commercially operated public mobile phone network in Finland. ... 1G (or 1-G) is short for first-generation wireless telephone technology, cellphones. ... For other meanings of the abbreviation, see: NMT. NMT (Nordisk MobilTelefon or Nordisk MobilTelefon-gruppen, Nordic Mobile Telephony in English) is a mobile phone system that was created in 1981 as a response to the increasing congestion and heavy requirements of the ARP mobile phone network. ... This article is about AMPS, the North American mobile phone system standard; AMPS is also an initialism for the All Media and Products Survey published by the South African Advertising Research Foundation. ... 2G (or 2-G) is short for second-generation wireless telephone technology. ... The Global System for Mobile Communications (GSM) is the most popular standard for mobile phones in the world. ... The title of this article is incorrect because of technical limitations. ... IS-54 and IS-136 are second-generation (2G) mobile phone systems, known as Digital AMPS (D-AMPS). ... Interim Standard 95 (IS-95), is the first CDMA-based digital cellular standard pioneered by Qualcomm. ... Personal Digital Cellular (PDC) is a 2G mobile phone standard developed and used exclusively in Japan. ... 2. ... General Packet Radio Service (GPRS) is a mobile data service available to users of GSM mobile phones. ... CDMA2000 is a 3G mobile telecommunications standard that uses CDMA, a modulation scheme for digital radio, to send voice, data and signaling data (such as a dialed telephone number) between mobile telephones and cell sites. ... A 2G mobile phone is a circuit switched digital mobile phone. ... Enhanced Data rates for GSM Evolution (EDGE) is a digital mobile phone technology which acts as a bolt-on enhancement to 2G and 2. ... 3G (or 3-G) is short for third-generation mobile telephone technology. ... W-CDMA (Wideband Code Division Multiple Access) is a type of 3G cellular network. ... Universal Mobile Telecommunications System (UMTS) is one of the third-generation (3G) mobile phone technologies. ... Foma is the name of a Czech Photographic film factory and trademark of its production( [[1]] ). Foma (with a stress on the second syllable) is a Russian form of the name Thomas. ... CDMA2000 is a 3G mobile telecommunications standard that uses CDMA, a modulation scheme for digital radio, to send voice, data and signaling data (such as a dialed telephone number) between mobile telephones and cell sites. ... TD-SCDMA (Time Division Synchronous Code Division Multiple Access) is a 3G mobile telecommunications standard, being pursued in the Peoples Republic of China by the Chinese Academy of Telecommunications Technology (CATT), Datang and Siemens AG, in an attempt to develop home-grown technology and not be dependent on Western... High-Speed Downlink Packet Access or HSDPA is a mobile telephony protocol. ... High-Speed Downlink Packet Access or HSDPA is a mobile telephony protocol. ... This article describes the wireless access technology 4G. For the 4G IATA code see Shenzhen Airlines 4G (or 4-G) is short for fourth-generation the successor of 3G and is a wireless access technology. ...

These phones were usually half-duplex (PTT, or Push-To-Talk, operation) over a single VHF or UHF radio channel.

This service was used at least into the 1980's in British Columbia and Vancouver, Canada.

This protocol was replaced by IMTS (Improved Mobile Telephone System). The Improved Mobile Telephone Service (IMTS) is a pre-cellular VHF/UHF radio system that links to the PSTN. IMTS had originally only sixteen channels and were prone to network congestion and interference by others keying up their radios while a converstaion was already occurring on a channel. ...