handsets

A handset is a component of a telephone that a user holds to the ear and mouth to receive audio through the receiver and speak to the remote party via the built-in transmitter.
In earlier telephones the transmitter was mounted directly on the telephone itself, which was attached to a wall at a convenient height or affixed to a desk stand.
Until the advent of the cordless telephone, the handset was usually wired to the base unit, typically by a flexible tinsel wire.
The handset of a cordless telephone contains a radio transceiver which relays communication via a base station that is wired to the telephone line. A mobile phone does not require a base station and communicates directly with a cell site in specially designated frequency bands.

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