The Dolby Frame Synchronizer DP583 synchronizes Dolby E, Dolby Digital, and PCM audio to your broadcast, cable, or satellite plant reference. Unlike conventional audio synchronizers that work only with PCM audio, the Dolby DP583 Frame Synchronizer can sync Dolby Digital and Dolby E bitstreams from outside (asynchronous) sources to your local reference. This enables to align the guard band on Dolby E bitstreams for switching and editing, allow Dolby E and Dolby Digital bitstreams to pass through headend and turnaround facilities, and maintain A/V sync. The DP583 can operate with both tracking and fixed delays of up to a maximum of 310 ms. When tracking with Dolby E, the video reference provides framing information; when tracking with PCM, a standard TTL input signal compatible with most video frame synchronizers can be used. The output clock can be derived from either a video black or AES reference. The DP583 displays the incoming bitstream type (Dolby E, Dolby Digital, or PCM), the program configuration, and the current delay through the unit. It also counts the number of frame drops or repeats for subsequent retrieval, and logs any errors discovered in Dolby E and Dolby Digital bitstreams. Redundant power supplies with separate inputs assure fail-safe operation in broadcast-critical paths.