What may cause the 30 Frame video deck not synchronize reliably?
This problem happens often in the initial setup of the TLC Dual Sync Mode. In order to properly synchronize any deck at any sync rate, the vertical signals feeding the TLC much closely match the vertical (field and frame) signals feeding or referencing the deck. In the old analog days, this was normally the case as any video delays were hard to come by. In the digital world, there are often many delays in the system. Delays that are not exact multiples of the video frame rate make timing of the video signals and the edit control commands not match. If the TLC sends a field 1 edit command during the TLC field one and it connects to a recorder where the video feeding it is in the end of field 2, there would be edit errors along with possible synchronizing errors. One method of testing this alignment is to compare on a dual trace scope, the 60i Vertical Drive to the TLC with the video feeding the 30 frame decks. Generally a digital signal may be converted to analog with minimum timing del
