| 摘要 |
<p>@ Apparatus for regenerating a clock pulse signal from a stream of data derived from a variable-speed digital video tape recorder (20) and lacking a strong clock pulse component, comprises a first phase-locked loop circuit (21) to which the incoming data is supplied and which includes a loop filter (34) of relatively wide bandwidth and a first voltage controlled oscillator (35). The first voltage controlled oscillator (35) supplies a regenerated clock pulse signal to a second phase-locked loop circuit (22) which includes a loop filter (38) of relatively narrow bandwidth and a second voltage controlled oscillator (39) which supplies a regenerated output clock pulse signal. The first and second voltage controlled oscillators (35, 39) are controlled by a preset control signal derived by a preset control signal generator arrangement (23) in dependence on the direction and speed of a magnetic tape (10) from which the video tape recorder (20) is reproducing the stream of data.</p> |
