Cd Error Detector

CD ERROR DETECTOR T. Giffard As almost any owner of a CD player must have noted at some time, serious scratches and other surface irregularities on compact discs cause sound reproduction errors that are beyond the capabilities of the error correction circuits in the player. The present circuit gives a reliable indication of the quality of the CD by counting the number of playback errors. The degree of redundancy built into the digital coding system used for compact discs allows complex electronic circuitry to detect and correct many errors as the disc is playing. The actual correction oper- ations go unnoticed by the listener, but do have their practical limits. The present error detector is a 4-digit counter with a maximum count of 9999. The circuit is suitable for use with any CD player that incorporates signal processing ICs of the second or third generation from Philips Components. The counter is connected to the error detection output on the laser control and error correction...