| 摘要 |
PURPOSE:To obtain an NHZ system magnetic card reader which can read out data accurately with high interchangeability secured between devices, by extracting a data signal synchronously with the clock signal passed through a delay circuit having the variable delay time. CONSTITUTION:A clock signals are supplied to delay circuits 9, 13 and 14 and delayed by times T4, T5 and T6 respetively. A data selector 15 selects a single signal out of those delay outputs. Then an RSFF11 is set and also reset by a delay circuit 10 after the time T2. The output of the FF11 is turned into a read clock signal. While the data signal sent from a peak detecting circuit 8 sets an RSFF12. Then the FF12 is reset with the rise of the negative logicaloutput of the FF11. The output of the FF12 is turned into a read data signal. Then data can be read out accurately by selecting the delay circuits 9-14 by an external control circuit like a CPU, etc.
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