Rotates - videodisc with a correction of errors in the time base plate and a constant angular velocity

摘要

The invention relates to a rotating - videodisc which comprises a plate in order to rotate a disc has an angular speed predetermined and substantially constant, a transducer which restores the signal recorded, a means for processing signals hydroxyacetals corresponding to a first component of the signal restores, in order to produce a signal for correction of error in the time base, a means of the other hand, - reaction applying this correction signal by means of a transducer in a direction tending to reduce the errors in the time base of the signal restores, in order to form a system that is servo-controlled in closed loop, which has the tendency is formed a loop gain dependent of the radial position of the transducer with respect to the disk. / p & & p & according to the invention, a compensation means 40, 5062 of the loop gain answer has a second component of the signal restores for adjust the loop gain of the system slaved in closed loop. / p & & p & the invention applies in particular for the restitution of videodiscs.