| 摘要 |
Magnetic recording and reading apparatus and a method in which two modes of operation, read-after-write and read-only, for setting read signal amplitude qualification threshold are provided. In the read-after-write mode, a fixed amplitude qualification threshold is utilized, typically being fifty percent of the peak amplitude of a perfect dropout-free read signal. The read-only mode amplitude qualification threshold is derived from the average peak rectified read signal, and varies with it. The threshold is selected to provide that fraction of the average peak rectified read signal which gives the lowest acceptable dropout or error rate.
|
