Search results
Results from the WOW.Com Content Network
On an ordinary two-wire telephone line, off-hook status is communicated to the telephone exchange by a resistance short across the pair. When an off-hook condition persists without dialing, for example because the handset has fallen off or the cable has been flooded, it is treated as a permanent loop or permanent signal .
The Chicago Telephone Company Kedzie Exchange is a historic telephone exchange building located at 17 S. Homan Avenue in the East Garfield Park neighborhood of Chicago, Illinois, United States. Built in 1906–07, it was one of the many telephone exchanges built in Chicago in the late 19th and early 20th centuries as telephone use grew rapidly.
A telephone exchange automatically senses an off-hook condition of the telephone when the user removes the handset from the switchhook or cradle. The exchange provides dial tone at that time to indicate to the user that the exchange is ready to receive dialed digits.
The off-hook tone in exchanges of the North American Numbering Plan consists of a superposition of tones with the frequencies 1400 Hz, 2060 Hz, 2450 Hz, and 2600 Hz, played at a cadence of 100 ms on and 100 ms off. [1]
The telephone operator will greet each call participant, gather specific information from each participant, introduce key speakers, and manage questions and answers, all from the telephone. A third number call or third party call is an operator assisted telephone call that can be billed to the party other than the calling and called party. The ...
It is the simplest of the telephone signaling systems, and uses the presence or absence of loop current to indicate the off-hook and on-hook loop states, respectively. It is used primarily for subscriber line signaling. An extension of the protocol that adds disconnect supervision is often called kewlstart.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
A dial tone (dialling tone in the UK) is a telephony signal sent by a telephone exchange or private branch exchange (PBX) to a terminating device, such as a telephone, when an off-hook condition is detected. It indicates that the exchange is working and is ready to initiate a telephone call. The tone stops when the first dialed digit is recognized.