PURPOSE: To improve the ratio between Tmax and Tmin substantially by especially reducing the maximum value of a run-length for the recording code of d=2.
CONSTITUTION: In an NRZL recording for data bits, a first record coding means 1 performs the record coding, wherein the shortest run-length (in NRZL record coding) (d) has the characteristic of 2, and a second record coding means 2 are provided. The second record coding means 2 divides the signal series at every 2 bits in the signal-waveform series Dn(n indicates each bit) and performs the non-inversion and inversion of the signal in response to the divided signal. After the second record coding, the signal is sent through a record amplifier circuit 3, a tape head system 4, reproducing amplifier circuit 5 and an equalizing means 6. The signal is recorded in a recording medium and or sent into a transmission line. The reproduced signal from the recording medium or the signal received from the transmission line is made to be a specified equalized waveform signal with the compensating characteristic corresponding to the record reproducing system or the transmission characteristic. Furthermore, a means 7, which performs identification in 2-bit unit, and a means 8, which decodes the result of the identification into the original data bits, are provided in this constitution.
ISHII HIROTAKE
KUDO KOJI
