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A telephone magneto is a hand-cranked electrical generator that uses permanent magnets to produce alternating current from a rotating armature. In early telegraphy , magnetos were used to power instruments, while in telephony they were used to generate electrical current to drive electromechanical ringers in telephone sets and activate signals ...
Kellogg company logo as used from the 1920s to the 1950s. The Kellogg Switchboard and Supply Company was an American manufacturer of telecommunication equipment. Anticipating the expiration of the earliest, fundamental Bell System patents, Milo G. Kellogg, an electrical engineer, founded the company in 1897 in Chicago to produce telephone exchange equipment and telephone apparatus.
Lister D. The Lister D is a 1 - 2.5hp stationary engine on petrol or petrol/paraffin (fuel) built between 1926-1965 by R A Lister and Company of Dursley. It is popular with newcomers to the stationary engine hobby with un-restored examples available for as little as £25, plenty of spares and various re-manufactured parts and decals.
The first field telephones had a battery to power the voice transmission, a hand-cranked generator to signal another field telephone or a manually-operated telephone exchange, and an electromagnetic ringer which sounded when current from a remote generator arrived. This technology was used from the 1910s to the 1980s.
The 5302 telephone. The model 5302 telephone was a look-alike product to the 500-type telephone that was introduced as a stopgap by Western Electric in 1955 to meet the increasing post-World War II demand for a modernized telephone. It reused existing component supplies from the older model 302 that the model 502 replaced. The 302 had been ...
In 1983, in Bryant Pond, Maine, Susan Glines became the last switchboard operator for a hand-crank phone when that exchange was converted. [14] Manual central office switchboards continued in operation at rural points like Kerman, California , [ 15 ] and Wanaaring, New South Wales , as late as 1991, but these were central-battery systems with ...
The model 302 telephone is a desk set telephone that was manufactured in the United States by Western Electric from 1937 until 1955, and by Northern Electric in Canada until the late 1950s, until well after the introduction of the 500-type telephone in 1949. The sets were routinely refurbished into the 1960s.
After this time several new Design Line series telephones were marketed and discontinued. One example of a "Design Line" phone was model 140, marketed in the mid 90s. The phone was similar in size to the 2554 wall phone, but had unique features: Round buttons; Round receiver/microphone; Switchhook similar in shape to a slice of pie; Desk or ...