Pocket watch with quarter repetition
(Also Repetition watch, repeater)
Repetition means the repeated playing of an acoustic signal at a clock or watch. In mechanical watches this requires a special, expensive additional mechanism (complication), the repetition carillion (see below).
Repetitions are well known by the sounds played by church tower clocks (Big Ben, for instance).
Essentially there are repetitions of the following type
Due to the high mechanical effort repetitions are regarded as one of the most value-adding complications in a mechanical watch.
To represent the time acoustically, the carillion (or chime movement) needs power. This it activated by the operation of a slider or pusher at the case edge. At the same time, this process also triggers the percussion mechanism. If pusher or slide have not been moved to the stop, simple repeaters beat the time incompletely. In fine constructions this is prevented by a so-called all-or-nothing switch. They then repeat properly or not at all.