Crystal Vision has added new features to the Safe Switch 3G, which provides fail-safe 2 x 2 switching between two 3Gb/s, HD or SD sources containing up to four groups of embedded audio and uses a full framestore synchroniser on each input and loss of reference protection to guarantee a clean switch. Ideal for planned maintenance switches or as a sophisticated auto changeover switch, the new features allow Safe Switch 3G to cope with signal path delays of up to 25 frames, add two new fault conditions (frozen or missing timecode) for the intelligent auto switching, and allow the user to define what constitutes a fault separately for each input.
Ideal for use on the final output stage of a transmission system before the signal gets to the MPEG encoder, Safe Switch 3G can now cope with signal path delays of +/-25 frames between the two inputs. Often the backup signal going into the switch will have been routed through less processing equipment and so gone a simplified route compared to the main programme, and therefore arrive several frames earlier than the main input which can upset the MPEG encoder on a switch to backup. With this new feature, input timing differences greater than one frame can be corrected by delaying the earliest arriving input by up to 25 frames in one frame steps. Input timing differences up to one frame will continue to be automatically corrected by the two existing on-board framestore synchronisers.
Safe Switch 3G can now choose from 18 different fault conditions to automatically trigger a switch, with the addition of two new fault parameters. Safe Switch 3G constantly checks both of the inputs so that the output of the switch always remains valid, and can be set to automatically switch away from the user-selected input based on the engineers selection of which faults are significant. The two new fault parameters are frozen Ancillary Timecode within the video stream, where it switches either immediately or after a delay of up to 120 seconds, and missing Ancillary Timecode. The other 16 fault conditions that can be used to auto-trigger a switch are input missing, input video standard incorrect, EDH missing, EDH full field error, EDH active picture error, line CRC error, audio group 1 missing, audio group 2 missing, audio group 3 missing, audio group 4 missing, active video black, active video frozen and audio silence in a selected group.
The final new feature is the ability to decide what constitutes a fault separately for each input. Previously Safe Switch 3G could either ignore or look at both inputs for each fault condition. Now the user can specify what he cares about on each signal and the logic will select the best input. This new feature adds extra flexibility and provides a solution in situations where the backup signal may not contain everything required in the main signal, allowing selection between signals with different characteristics such as a live feed and an inherently frozen apology caption on the backup.
Safe Switch 3G is a space-saving 100mm x 266mm module which fits in the standard Crystal Vision frames and provides a robust, one-board solution that replaces a switch and two synchronisers, simplifying system designs and saving broadcast engineers both money and rack space.
The new features are all available now.
Based at Whittlesford near Cambridge in the UK, Crystal Vision provides digital keyers, picture storage modules and a full range of interface equipment including converters, synchronisers, distribution amplifiers and audio embedders to the professional broadcasting industry worldwide.