| 摘要 |
PURPOSE:To check the disconnection of a lead wire in a camera by providing a feeding capacitor for an electric load fed through the lead wire and judging the lead wire to be disconnected if the terminal voltage does not fall to a prescribed value or lower. CONSTITUTION:If the lead wire of the coil 9 of an electromagnetic shutter is disconnected, an exciting current is not flowed to the coil 9 even when the signal SD1 of '0' and a signal SD2 of '1' are given to a shutter driven 8 from a controller 4, and a capacitor C is not discharged quickly after the second power supply signal PHS is terminated, and therefore the second supply voltage VB2 falls slowly consequently. Since the output of a comparator 11 is in the low level as it is at the timing (t) of disconnection check, the controller 4 discriminates the disconnection of a lead wire (l). The disconnection is reported to a user by lighting a warning lamp or the like. Thus, unnecessary photographing operation and film consumption are eliminated by this check before photographing to get desired pictures surely.
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