The ability to place the visual text of an EAS message over programming and switch the audio is an FCC requirement under Part 11 rules. While there are several ways to accomplish this task, the least disruptive to the viewer is to use a crawl generator and audio switch.

Unfortunately, creating HD and SDI EAS messages can require multiple pieces of gear. This might include an HD character generator, de-embedder, audio switch, and embedder. The process isn't necessarily onerous for a single program stream, but it becomes complex and expensive when dealing with multiple program streams. 

The new ChyTV HD-EAS system from Digital Alert Systems and DigIt Signage Technologies combines all the components necessary to support a single-channel, EAS-enabled program stream into one chassis. Simple connections are used to drive up to eight additional ChyTV devices.

The ChyTV HD-EAS is available in two models: a 3-RU rack-mount chassis with redundant power supplies, or a desktop PC version with a single power supply. Both models come with a GPI I/F module and CG software. The DASDEC requires the TV-Plus package or either the MultiStation-2 or MultiStation-5 option be already installed.

Because the per-stream cost now becomes significantly lower, stations can improve the viewer experience by using simple crawls rather than program-interrupting, full-screen displays. Also, the system supports both SD and HD formats, giving SD stations a seamless upgrade path to HD without the need to purchase additional equipment.