Introduced by AT & T in 1963, the Touch-Tone system using the telephone keypad gradually replaced the use of rotary dial and has become the industry standard for landline service.

A German Fe TAp 615, ( R & g ) a widespread rotary dial telephone of the 1960s to the 1980s

The rotary dial is a device mounted on or in a telephone or switchboard that is designed to send electrical pulses, known as pulse dialing, corresponding to the number dialed.

The early form of the rotary dial used lugs on a finger plate instead of holes.

Almon Brown Strowger filed the first patent for a rotary dial, U. S. patent # 486, 909, on December 21, 1891, that was later issued to him on November 29, 1892.

The modern version of the rotary dial with holes was first introduced in 1904 but did not enter service in the Bell System until 1919.

The rotary dial was gradually supplanted by Dual-tone multi-frequency pushbutton dialing, introduced at the 1962 World's Fair, which uses a keypad instead of a dial.

The rotary dial was invented by Almon Brown Strowger in 1891.

A traditional North American rotary phone dial.

A 1931 Ericsson rotary dial telephone, without associative lettering, typical of European telephones.

Older Australian rotary dial telephones also had letters, but the combinations were often printed in the center plate adjacent to the number.

The back of a rotary dial in operation, with LEDs attached making the contacts ' states visible.

A rotary dial, 18-button AT & T Call Director.

Rotary dial telephones in Australia were sometimes equipped, in later years, with touch pad blanks, designed to look like a touch-phone, but providing the rotary dial signalling required by the Australian phone system.

An Olivetti rotary dial | rotary dial telephone, c. 1940s

The signaling equipment, or ringer, ( see figure 1 ) consists of a bell, beeper, light or other device ( A7 ) to alert the user to incoming calls, and number buttons or a rotary dial ( A4 ) to enter a telephone number for outgoing calls.

The native mode of communication for a teleprinter is a simple series DC circuit that is interrupted, much as a rotary dial interrupts a telephone signal.

Middle 20th century rotary dial telephone

Pulse dialing, dial pulse, or loop disconnect dialing, also called rotary or decadic dialling in the United Kingdom ( because up to 10 pulses are sent ), is pulsing in which a direct-current pulse train is produced by interrupting a steady signal according to a fixed or formatted code for each digit and at a standard pulse repetition rate.

However by 1783 the more economical Watt steam engine had been fully developed into a double-acting rotative type with a centrifugal governor, parallel motion and flywheel which meant that it could be used to directly drive the rotary machinery of a factory or mill.

This technique is referred to as vacuum distillation and it is commonly found in the laboratory in the form of the rotary evaporator.

* In rotary evaporation a vacuum distillation apparatus is used to remove bulk solvents from a sample.

Linear motion can come from either a diaphragm or piston actuator, while rotary motion is supplied by either a vane type air motor or piston air motor.

The euphonium is a valved instrument ; nearly all current models are piston valved, though rotary valved models do exist.

Moller International continues to develop the Skycar M400, which is powered by four pairs of in-tandem Wankel rotary engines, and is approaching the problems of satellite-navigation, incorporated in the proposed Small Aircraft Transportation System.

First introduced at AirVenture 2008, the Switchblade is to utilize a single Wankel rotary engine and ducted fan to keep the propeller out of harm's way on the ground.

Cardano invented several mechanical devices including the combination lock, the gimbal consisting of three concentric rings allowing a supported compass or gyroscope to rotate freely, and the Cardan shaft with universal joints, which allows the transmission of rotary motion at various angles and is used in vehicles to this day.

There is no rail service in town but the Cape Cod Rail Trail rotary is located in North Harwich near Main Street.

The clay is formed into round pellets and fired in rotary kilns at.

The term internal combustion engine usually refers to an engine in which combustion is intermittent, such as the more familiar four-stroke and two-stroke piston engines, along with variants, such as the six-stroke piston engine and the Wankel rotary engine.

A gas turbine is a rotary machine similar in principle to a steam turbine and it consists of three main components: a compressor, a combustion chamber, and a turbine.

A gas turbine is a rotary machine somewhat similar in principle to a steam turbine and it consists of three main components: a compressor, a combustion chamber, and a turbine.

It differs from an axis lock in that the cylindrical bearing is tensioned by a rotary spring rather than an axial spring.

Once prepared, the stencil is wrapped around the ink-filled drum of the rotary machine.

This reaction is driven by the proton flow, which forces the rotation of a part of the enzyme ; the ATP synthase is a rotary mechanical motor.

The activating mechanism is often reciprocating or rotary.

* Gear pumps-a simple type of rotary pump where the liquid is pushed between two gears.

This is the simplest of rotary positive displacement pumps.

Screw pumps are a more complicated type of rotary pumps, featuring two or three screws with opposing thread —- that is, one screw turns clockwise, and the other counterclockwise.

As with other forms of rotary pumps, the clearance between moving parts and the pump's casing is minimal.

For the design engineer, the visible air gap that the sensor ends up with is primarily the result of the specific machine design, but is subject to whatever constraints are needed to register the rotary speed.