Search results
Results from the Go Local Guru Content Network
Introduced to the public in 1963 by AT&T, Touch-Tone dialing greatly shortened the time of initiating a telephone call. It also enabled direct signaling from a telephone across the long-distance network using audio-frequency tones, which was impossible with the rotary dials that generated digital direct current pulses that had to be decoded by ...
DTMF was first developed in the Bell System in the United States, and became known under the trademark Touch-Tone for use in push-button telephones supplied to telephone customers, starting in 1963. DTMF is standardized as ITU-T Recommendation Q.23. It is also known in the UK as MF4.
The ten-button Touch Tone version was known as the 1702B, and when twelve-button keypad were introduced the phone was labeled as 2702B. The modular cord version of this was the 2702BM. Several other variants existed. The Princess underwent several changes in its production run:
CEFCU, the leading Central Illinois credit union, agreed to be the presenting sponsor for the American Lung Association in Illinois’ Fight For Air Climb at Wyndham Springfield City Centre, set ...
Touch-tone. The international standard for telephone signaling utilizes dual-tone multi-frequency (DTMF) signaling, more commonly known as touch-tone dialing. It replaced the older and slower pulse dial system.
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.
Touch-tone. North Electric introduced a touch-tone version of the Ericofon in the United States in 1967. Production of this variant was much lower than that of the rotary-dial Ericofons.
Speed dial. Speed dial is a function available on many telephone systems allowing the user to place a call by pressing a reduced number of keys. This function is particularly useful for phone users who dial certain numbers on a regular basis.
The NEC μPD7720 is the name of fixed point digital signal processors from NEC (currently Renesas Electronics ). Announced in 1980, it became, along with the Texas Instruments TMS32010, one of the most popular DSPs of its day.
This page was last edited on 26 June 2011, at 10:15 (UTC).; Text is available under the Creative Commons Attribution-ShareAlike License 4.0; additional terms may ...