| 摘要 |
PURPOSE:To prevent the timing loss to rewind a tape to the tape beginning, by storing a counted value of the optimum automatic gain control for plural magnetic tape running speeds, and providing the optimum gain at the retrial of data block. CONSTITUTION:Reading amplifiers 9-11 amplify outputs of readout heads 6-8, and supply the result to a magnetic tape controller. A magnetic tape device detects the depression of a load button, starts the loading of a magnetic tape, stops when a BOT marker of the tape beginning display is detected, runs a magnetic tape speed of the head 6, reads out the recording density of the tape with a recording density identification ID, reads out an ARA burst when 6250 rpi is detected and stores a count value in a counter 12. Similarly, the tape device stores count values in counters 13-15. In reading out the data block stored at the 6250 rpi, the tape running speed from the MODE is fed to a multiplexer 16, the counted value of AGC of the counter corresponding to the running speed is transmitted to amplifiers 9-11 at the multiplexer 16 and amplified at the optimum gain. |
