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DTMF was known throughout the Bell System by the trademark Touch-Tone. The term was first used by AT&T in commerce on July 5, 1960, and was introduced to the public on November 18, 1963, when the first push-button telephone was made available to the public.
Pressing a single key of a traditional analog telephone keypad produces a telephony signaling event to the remote switching system. For touchtone service, the signal is a dual-tone multi-frequency signaling tone consisting of two simultaneous pure tone sinusoidal frequencies. The row in which the key appears determines the low-frequency ...
A push-button telephone is a telephone that has buttons or keys for dialing a telephone number, in contrast to a rotary dial used in earlier telephones.. Western Electric experimented as early as 1941 with methods of using mechanically activated reeds to produce two tones for each of the ten digits and by the late 1940s such technology was field-tested in a No. 5 Crossbar switching system in ...
1 November 1960: The Bell System begins testing its push-button phone, starting with service in Findlay, Ohio. [39] 1960: Bell Labs conducts extensive field trial of an electronic central office in Morris, Illinois, known at the Morris System. 1960s: Bell Labs developed the electronics for cellular phones; 1961: Initiation of Touch-Tone service ...
A breakthrough new technology was the introduction of Touch-Tone signaling using push-button telephones by American Telephone & Telegraph Company (AT&T) in 1963. [ 23 ] Ericsson DBH 1001 (ca. 1931), the first combined telephone made with a Bakelite housing and handset.
Multifrequency signaling is a technological precursor of dual-tone multi-frequency signaling (DTMF, Touch-Tone), which uses the same fundamental principle, but was used primarily for signaling address information and control signals from a user's telephone to the wire-center's Class-5 switch. DTMF uses a total of eight frequencies.
A 220 Trimline rotary desk phone, showing the innovative rotary dial with moving fingerstop Early Touch Tone Trimline with round buttons and clear plastic backplate and round non-modular handset cord Redesigned touch-tone desk model Trimline, manufactured on January 9, 1985 The Trimline 2225, one of the last phones made at the Indianapolis Works in 1986 Early foreign made Trimline, December ...
Single Frequency supervision tone : US SIP: Session Initiation Protocol: US SP Lock: Unlocking: UK SS7: Signaling System 7 STD: Subscriber trunk dialling: UK and India T-CXR: T-carrier (e.g. T-1) US TAPI: Telephony Application Programming Interface TR: Tip and ring: US TSPS: Traffic Service Position System TXE: Telephone eXchange Electronic: UK UAX