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Hamlin, Inc. was an American manufacturer of reed switches and other components, founded in 1949. Hamlin are best known for producing reed capsules (commonly known as reed switches) but they did also produce complete pushbutton switches.

On the 15th of April 2013, an agreement was signed for Littelfuse to acquire Hamlin, Inc. from Key Safety Systems.


Reed capsules

Hamlin’s product line included reed capsules. Typically known as reed switches, or “magnetic reed” switches to some manufacturers including Hamlin, these are hermetically-sealed cylindrical glass enclosures containing one or more pairs of switch contacts. There is no actuator: any arrangement involving an operating magnet must be provided separately.

Peter Cherry recollects that Hamlin was Cherry’s reed switch supplier, meaning that Hamlin reed capsules would have been used in Cherry’s short-lived reed keyboard switches.

Hamlin placed an advertisement in the Electronic Engineer magazine in November 1971 for their Mark 6 keyboard reed switches. These are compact reed capsules designed to fit inside keyboard switches, with a glass enclosure of 0.560″ (14.2 mm) in length and 0.105″ (2.67 mm) in diameter. The advertisement appears to also depict a few keys from a keyboard.

Reed pushbutton switches

Hamlin did also package up their reed capsules into discrete pushbutton switches. Such switches can be seen in an eBay listing for P401/RR reed keyboard switches. These switches are said to be 20 × 17 mm at the top, which puts them outside of the 19.05 mm spacing of keys on a keyboard. The shop in question only went so far as to indicate that the measurements are not very accurate, so there is a small chance that these do confirm to keyboard spacing.


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