PURPOSE: To simplify the constitution of alarm sound producing part and achieve the smaller size, lighter weight and higher reliability of the watch by detecting the time, etc. as serial signals and setting the alarm time, etc. in a presettable counter.

CONSTITUTION: The serial signal of the alarm set time of the time detecting part 202 which makes non-contact detection of the slits 302 ... provided to a rotator 301 turning together with the hour hand with an optical sensor 303 is set in a presettable counter 201. This causes the set alarm to be announced via oscilation circuit 204, envelope circuit 205, etc. by the coincidence signal with the time signal of an oscillation circuit 203. Hence, the desired time is set in the counter 201 without using parallel binary codes of plural bits from the watch circuit, thus the constitution of the alarming circuit is simplified and the watch of a small size, lightweightness and high reliability may be provided. If in the initial state at the battery exchanging, etc. the resetting of the time setting is released after making hand turning of passing through the specified time beforehand, then the occurrence of false alarm is prevented.