Chinese repeater watches
A repeater is a watch containing a device whereby the current time is delivered on demand as an audible signal. This is achieved by a set of small hammers and gongs triggered by a button or slider. Specific tones denote different time intervals, which add up to the current time. The position of the hand train determines the sequence of tones.
A quarter-repeater tells the time to the nearest quarter-hour, using one tone to count out the hours, and another to count the quarters.
A minute-repeater adds an additional tone, or combination of two tones, to count the time in increments of hour, quarter and minute.
Current Chinese Repeaters
Two manufacturers have so far mastered the art of repeater manufacture; Sea-Gull and Beijing Watch Factory.
In 2006, the Sea-Gull ST9000 became the first Chinese-made quarter-repeater, with a limited production run of 50 pieces debuted at Basel International Watch Fair. That same year Sea-Gull completed the ST9100 minute-repeater prototype. This appears to be a substantially different design to the ST9000. In 2009 the ST9100 entered limited production. The ST9150 combines a minute-repeater and perpetual-calendar.
Beijing Watch Factory has successfully combined the functions of minute-repeater and tourbillon in their MRB-1, which was added to their catalogue in 2009. Orders are limited to a maximum 20 pieces.