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A ring generator or ringing voltage generator is a device which outputs 20 cycle sinusoidal AC at up to 110 volts peak to power bells or annunciators in one or more telephone extensions. [4] The output stops if a handset is taken off the hook. In terminology devised by phone phreaks, a ringing generator is a magenta box.
The exchange then places a reverting call to the originating line, causing the telephone to ring. When answered, the exchange plays a verification tone. The verification tone is issued so that telephone subscribers cannot easily use the ringback system as an intercom between multiple stations in a residence on the same line by taking the ...
A Panasonic answering machine with a dual compact cassette tape drive to record and replay messages. An answering machine, answerphone, or message machine, also known as telephone messaging machine (or TAM) in the UK and some Commonwealth countries, ansaphone or ansafone (from a trade name), or telephone answering device (TAD), is used for answering telephone calls and recording callers' messages.
In most cases, two copper wires (tip and ring) for each telephone line run from a home or other small building to a local telephone exchange. There is a central junction box for the building where the wires that go to telephone jacks throughout the building and wires that go to the exchange meet and can be connected in different configurations ...
Less than $200 million over 20 years: It’s chump change for intruders who make landline use unbearable. Not much of a problem, some “experts” say, since only about one-third of Americans ...
Telephone numbers listed in 1920 in New York City having three-letter exchange prefixes. In the United States, the most-populous cities, such as New York City, Philadelphia, Boston, and Chicago, initially implemented dial service with telephone numbers consisting of three letters and four digits (3L-4N) according to a system developed by W. G. Blauvelt of AT&T in 1917. [1]
The voltage at a subscriber's network interface is typically 48 V between the ring and tip wires, with tip near ground (slightly negative relative to ground) and ring at −48 V relative to tip. In the middle 20th century, long loops in many rural areas of North America used range extenders, which operated at 100 or 130 volts to ensure reliable ...
Landline service is typically provided through the outside plant of a telephone company's central office, or wire center. The outside plant comprises tiers of cabling between distribution points in the exchange area, so that a single pair of copper wire, or an optical fiber, reaches each subscriber location, such as a home or office, at the network interface.