摘要 |
A record carrier (1) is described which has a servo track (4) indicating an information track (9) intended for recording information blocks represented by marks, which servo track (4) has a periodic variation of a physical parameter at a first frequency and modulated parts for encoding record carrier information. The modulated parts have a bit synchronization element constituted by a phase modulation of the periodic variation and a data part comprising data bits of the record carrier information encoded by direct digital modulation. Alternatively the modulated parts comprise a second frequency which is substantially different from the first frequency for encoding data bits of the record carrier information, the second frequency being an integral multiple N of the first frequency. A recording and/or playback device has means for recording/reading the information blocks and for reading the record carrier information.
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