| 摘要 |
<p>PURPOSE:To make the copy of a PCM sound signal by the reproduction of a record recorded on other device impossible by forming nonlinearly the magnetic track of the PCM sound signal at the time of recording, and muting the PCM sound signal if the error rate of the PCM sound signal is large at the time of the reproduction. CONSTITUTION:In the case of the reproduction of the record recorded on other device, since the scanning loci of the tracks 2A, 2V and heads 1A, 1B are distorted, and simultaneously, the distortions of the both do not generally coincide with each other, the heads 1A, 1B come to be incapable of scanning correctly the tracks 2A, 2V. Accordingly, since the error rate of the reproduced PCM sound signal SA becomes large, the signal DA comes to be muted in a processing circuit 57, and the sound signals L, R are not signaled to a terminal 59. Thus, in the case of the reproduction of the record recorded on other device, the sound signals L, R are not reproduced from the PCM sound signal SA, and it is prevented from being copied without permission.</p> |
