| 摘要 |
A disc servo pattern and servo detector for use in a system for reading and writing data on a magnetic disc. The magnetic disc has a servo data area formatted with a multiplicity of servo tracks which are formatted with a 1F-2F servo pattern. Each servo frame has a single sync pulse and a single position pulse at predefined positions. The 1F frames are those frames where the sync pulse and position pulse are of opposite polarity. The 2F frames are those where the sync and position pulses are of like polarity. Fill-in pulses separate neighboring sync and position pulses of like polarity. In a preferred embodiment the servo pattern in each servo track is the same as the servo pattern of the neighboring servo track shifted by one frame. Each track has a repeating pattern of two 1F frames followed by two 2F frames, and so on. The system has a servo head for reading a servo pattern on a magnetic disc and producing a servo carrier signal corresponding thereto. The servo detector generates a position signal proportional in amplitude and polarity to the extent and direction that the servo data head is off track. It includes an amplifier for amplifying the servo signal and producing a servo carrier signal. An integrator integrates the servo carrier signal and develops a position signal. A switch connects the servo carrier signal to integrator at times corresponding to the position pulses in a predefined pattern of the frames.
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