| 摘要 |
PURPOSE:To exclude production of noise by utilizing a time disabling to record/ reproduce a signal due to the structure of a rotary head magnetic recording and reproducing device, using a rotary transformer so as to send a high frequency signal for power and supplying power to a circuit such as a full wave rectifier circuit in a head drum. CONSTITUTION:An AF signal amplified by a recording amplifier 1 is fed to the primary side 6 of the rotary transformer only except for a format dropout period via a switch 2 switched by a recording/reproducing switching signal and a switch 3 switched by a format dropout signal. An output caused at the secondary side 7 of the transformer is fed to a full wave rectifier 12 for the format dropout period via a switch 9 controlled by a high frequency signal from a switch 8 connected to a changeover detector 11 and from the detector 11, fed to a recording/reproducing head 15 at the recording except for that period to obtain a device with high performance and stable operation without needing any maintenance. |
