Patent ID: 6867938

Claim:
A digital information reproducing apparatus using rotary magnetic heads that reproduces an information signal recorded on a magnetic tape, wherein magneto resistive heads, a current supply circuit supplying an operating current to said magneto resistive heads, and a reproduction amplifier circuit amplifying a signal reproduced by said magneto resistive heads are installed on a rotary drum, said apparatus comprising: a magnetic tape checking circuit installed in a fixed side of said apparatus that, when a magnetic tape to be reproduced is mounted on said apparatus, checks an open/close status of detection holes on a tape cartridge to determine a type of the magnetic tape, said tape cartridge storing therein the magnetic tape; a control signal generation circuit installed in the fixed side of said apparatus that generates a control signal for controlling a gain of said reproduction amplifier circuit; and a decoder circuit installed on said rotary drum that identifies data of the control signal transmitted from said control signal generation circuit; wherein said control signal generation circuit generates the control signal based on a checking result given by said magnetic tape checking circuit and said decoder circuit identifies the transmitted control signal to control the gain of said reproduction amplifier circuit.