| 摘要 |
PURPOSE:To obtain a time-limit warning device which never disturbs others by connecting an earphone, etc., to an alarm timepiece device. CONSTITUTION:A combination of a pulse number integrating circuit and a comparator is used so that hours or time is set normally. Then a gate circuit 3 which operates with the output of a comparator generated when the integral number of pulses becomes equal to the set number of pulses controls input from an audio frequency AC power source 1 to the earphone, etc. Consequently, a user is prevented from being carried beyond his or her destination station by a time-limit alarm tone to which sound volume is enough for the user as to a means of transportation without giving others in the environment trouble.
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