Claims
- 1. In a system for sensing a record medium having at least two possible recording states, the combination comprising:
- sensing means for producing a read signal in response to a change of state on said record medium; and
- data decoding means responsive to said read signal for detecting a cell boundary when two read signals occur within an interval not greater than one-half the time between cell boundaries and for producing data output signals when a single read signal occurs within cell boundaries.
- 2. The invention claimed in claim 1 further including error means responsive to said sensing means for producing an error signal when two changes of recording states indicate a change of state intermediate said last-mentioned two changes did not produce a read signal.
- 3. The invention claimed in claim 2 further including error correction means responsive to said error means and to said data decoding means for providing correction signals to said data decoding means.
- 4. The invention claimed in claim 1 wherein said sensing means includes waveshaping means responsive to said read signal for producing output signals indicative of the direction of change in recording state.
- 5. The invention claimed in claim 4 wherein said data decoding means includes pulse classification means responsive to the output signals from said waveshaping means for producing output signals indicative of a class of pulse.
- 6. The invention claimed in claim 5 including
- speed detection means responsive to said data decoding means for producing signals indicative of the speed of the relatively moving medium.
- 7. In a recording system for use with a record medium having at least two possible recording states, the combination comprising:
- pulse means for producing pulses at a predetermined rate;
- signal means responsive to said pulse means and to data to be recorded for producing a data signal when said data has a given value; and
- recording means responsive to said pulse means and to said signal means for recording on said record medium two successive changes of state in response to said pulses to indicate a cell boundary and a single change of state between successive cell boundaries in response to said data signal.
Parent Case Info
This is a division, of application Ser. No. 485,520, filed 7/3/74.
US Referenced Citations (3)
Divisions (1)
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Number |
Date |
Country |
Parent |
485520 |
Jul 1974 |
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