| 摘要 |
PURPOSE:To maximize a reproduced output and to prevent the degradation of picture quality by recording and reproducing a reference signal after the erasing operation in the state where running of a magnetic tape is stopped and changing a recording current in accordance with the reproduced output and repeating a series of these operations. CONSTITUTION:A magnetic tape T is wound around a rotary drum 70 and is run, and recording and reproducing heads 51 and 52 are used alternately in case of normal reproducing, and recording and reproducing heads 51 and 53 are used alternately in case of still picture reproducing, and reproduced signals are processed by a regenerative amplifying circuit 4 and a detecting circuit 5 after passing switch circuits 40 and 20 to output a reproduced signal Sp. When the recording current of this recording and reproducing device is set, each part is controlled by a microcomputer 60, and running of the drum 70 is stopped. Next, the erase operation is performed by the head 51 in accordance with the output of an erase signal generating circuit 7. The reference signal from a reference signal generating circuit 2 is recorded and reproduced, and the recording current is changed in accordance with the reproduced signal output, and these operations are repeated to maximize the reproduced output. |
