Time base correction system with coarse and fine correction

Claim 2

A time base control method in which, in effecting a coarse control and a fine control of time base in accordance with a relative speed between a recording medium and a signal reading means for reading a signal from said recording medium, a read signal obtained by said signal reading means is written into a memory successively from a predetermined address of said memory by using a write reset signal synchronized in phase with a predetermined signal component contained in said read signal, and said read signal written in said memory is read-out successively from said predetermined address by using a read-out reset signal generated at predetermined intervals, said time base control method being characterized by changing phases of generation of said read-out reset signal before and after a starting of a track jump operation by which a signal detection point of said signal reading means moves from a track section to another track section of said recording medium.

Claim 3

A time base control method for use in a system for reading information from a recording medium by means of a signal reading means, said system adapted to effect a coarse control and a fine control of time base in accordance with a relative speed between the recording medium and the signal reading means, said time base control method comprising the steps of: writing a read signal obtained by said signal reading means into a memory successively from a predetermined address of said memory by using a write reset signal synchronized in phase with a predetermined signal component contained in said read signal; reading-out said read signal written in said memory successively from said predetermined address by using a read-out reset signal generated at predetermined intervals; and changing phases of generation of said read-out reset signal before and after a starting of a track jump operation by which a signal detection point of said signal reading means moves from a track section to another track section of said recording medium.

Claim 4

A time base control method for use in a system for reading information from a recording medium by means of a signal reading means, said system adapted to effect a coarse control and a fine control of time base in accordance with a relative speed between the recording medium and the signal reading means, said time base control method comprising the steps of: writing a read signal obtained by said signal reading means into a memory successively from a predetermined address of said memory by using a write reset signal synchronized in phase with a predetermined signal component contained in said read signal; reading-out said read signal written in said memory successively from said predetermined address by using a read-out reset signal generated at predetermined intervals; and changing phases of generation of said read-out reset signal before and after a starting of a track jump operation by which a signal detection point of said signal reading means moves from a track section to another track section of said recording medium.

Claim 5

A time base control method as set forth in claim 2, wherein said step for changing phases of generation of read-out reset signal includes a step for resetting the phase of the read-out reset signal immediately after the completion of a track jump operation so that the phase difference between the read-out and write reset signals becomes equal to a predetermined value.

Claim 6

A time base control apparatus for use in a system for reading information from a recording medium by means of a signal reading means, said system adapted to effect a coarse control and a fine control of time base in accordance with a relative speed between the recording medium and the signal reading means, said time base control apparatus comprising: writing means for writing a read signal obtained by said signal reading means into a memory successively from a predetermined address of said memory by using a write reset signal synchronized in phase with a predetermined signal component contained in said read signal; reading means for reading-out said read signal written in said memory successively from said predetermined address by using a read-out reset signal generated at predetermined intervals; and control means for changing phases of generation of said read-out reset signal before and after a starting of a track jump operation by which a signal detection point of said signal reading means moves from a track section to another track section of said recording medium.

Claim 7

A time base control apparatus for use in a system for reading information from a recording medium by means of a signal reading means, said system adapted to effect a coarse control and a fine control of time base in accordance with a relative speed between the recording medium and the signal reading means, said time base control apparatus comprising: writing means for writing a read signal obtained by said signal reading means into a memory successively from a predetermined address of said memory by using a write reset signal synchronized in phase with a predetermined signal component contained in said read signal; reading means for reading-out said read signal written in said memory successively from said predetermined address by using a read-out reset signal generated at predetermined intervals; and control means for changing phases of generation of said read-out reset signal before and after a starting of a track jump operation by which a signal detection point of said signal reading means moves from a track section to another track section of said recording medium.

Claim 8

A time base control apparatus as set forth in claim 4, wherein said control means include means for resetting the phase of the read-out reset signal immediately after the completion of a track jump operation so that the phase difference between the readout and write reset signals becomes equal to a predetermined value.