Dual head type magnetic disk recording/reproducing apparatus

A dual head type magnetic disk recording/reproducing apparatus, in which a magnetic disk is inserted and/or from which said magnetic disk is ejected, said magnetic disk having a first surface and a second surface each of which is segmented into a plurality of tracks, each track having a corresponding track number, said dual head type magnetic disk recording/reproducing apparatus comprising:

• a first magnetic head which reproduces a first information signal from a first track on said first surface by establishing physical contact with said first surface;
• a second magnetic head which reproduces a second information signal from a second track on said second surface by establishing a physical contact with said second surface, said second magnetic head being offset in a radially outward direction with respect to said first magnetic head by a predetermined number of tracks;
• a resonance circuit, coupled to said first and second magnetic heads, to which said information signals reproduced by said first and second magnetic heads are supplied, said resonance circuit having a Q-factor that can be changed between a first predetermined value and a second predetermined value;
• control means, coupled to said resonance circuit, said control means being supplied with a control signal indicative of which one of said first and second magnetic heads 55 is to be used, for controlling said resonance circuit such that said Q-factor is set to said first predetermined value when said control signal indicates use of said first magnetic head and such that said Q-factor is set to said second predetermined value when said control signal indicates use of said second magnetic head;
• said first predetermined value being set larger than said second predetermined value to form a constant frequency offset upon switching from one side of said magnetic disk to the opposite side thereof independent of track position;
• such that said resonance circuit produces substantially an identical waveform when reproducing said first information signal and when reproducing said second information signal, provided that said first and second information signals are formed of a common information signal;
• and
• selection means, coupled to said first and second magnetic heads and said control means, for selecting either said first or second magnetic head under control of said control means and in response to said control signal, such that said first magnetic head is selected when said control signal indicates use of said first magnetic head, and such that said second magnetic head is selected when said control signal indicates use of said second magnetic head.

A dual head magnetic disk recording/reproducing apparatus, in which a magnetic disk is inserted and/or from which said magnetic disk is ejected, said magnetic disk having a first surface and a second surface each of which is segmented into a plurality of tracks, each track having a corresponding track number, said dual head type magnetic disk recording/reproducing apparatus comprising:

• a first magnetic head which reproduces a first information signal from a first rack on a first surface;
• a magnetic head which reproduces a second information signal from a second track on said second surface, said second magnetic head being offset in a radially outward direction with respect to said first magnetic head by a predetermined number of tracks that exist between said first track and said second track;
• a resonance circuit, coupled to said first and second magnetic heads, to which said information signals reproduced by said first and second magnetic heads are supplied, said resonance circuit having a resonance frequency that can be changed between a first predetermined resonance frequency and a second predetermined resonance frequency;
• control means, coupled to said resonance circuit, said control means being supplied with a control signal indicative of which one of said first magnetic head and said second magnetic head is to be used, for controlling said resonance circuit such that said resonance frequency is set to said first predetermined resonance frequency when said control signal indicates use of said first magnetic head and such that said resonance frequency is set to said second predetermined resonance frequency when said control signal indicates use of said second magnetic head;
• said first resonance frequency being set higher that said second resonance frequency to form a constant frequency offset upon switching from one side of said magnetic disk to the opposite side thereof independent of track position with said frequency offset selected such that said first information signal and said second information signal have substantially an identical output level;
• and
• selection means, coupled to said first and second magnetic heads and said control means, for selecting either said first or second magnetic head under control of said control means and in response to said control signal, such that said first magnetic head is selected when said control signal indicates use of said first magnetic head, and such that said second magnetic head is selected when said control signal indicates use of said second magnetic head.