RECORDING AND DETECTING MARKING SIGNALS

摘要

In recording and/or detecting two different marking signals on or from a record carrier, a generator for marking signals comprises at least one pulse generator which supplies marking signals in the form of two marking-pulse trains M1 and M2 having the same frequency but having different duty factors with the values k and 1-k respectively, which differ from 0.5. A detection circuit for detecting marking signals detects the duty factor of a marking pulse train M1 or M2 respectively and which supplies a specific detection signal in conformity with its detected pulse train.