| 摘要 |
PURPOSE:To clearly perform the sound recording of a sound from an object to be photographed regardless of a long distance to the object by providing a means which generates a bit of information corresponding to the distance to the object, and a control means which controls the sensitivity of a microphone based on the bit of information generated by the above stated means. CONSTITUTION:When the distance to the object is short and a microphone 4 is selected, the output of a comparator 9-1 is at an L level, and a signal of H level is inputted to an input terminal on one side of an AND3 through an inverter iNV2. Also, when a switch S5 is connected to (a) side, and it is a state where a sensitivity adjustment is performed, an input of H level is inputted to the terminal on the other side of the AND3, and its output becomes the H level, and a switch ASW1 is conducted. During the conduction of the ASW1, the output voltage VASW1 of the ASW1 is increased corresponding to the output of an operational amplifier 9-2, and the gain of an AMP is gradually raised. When the distance to the object exceeds over a prescribed distance, the microphone 4 is switched to a microphone 5, and the output of the AND3 is inverted to the L level, and the ASW1 is not conducted, and the gain of the AMP is decreased.
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