The LT 444 is a changeover unit that automatically switches from primary signals to the backup system signal when errors are detected. Normal operation will automatically switch the output signal from the primary channel to the backup channel when problems are detected in the primary signal. Additionally, the switching mode can be defined to switch as either automatic or by manual operation. Primary and backup system input signals are connected to each channel for detection of errors based on the specific amplitude of the primary input signal. Multiformat operation is facilitated through the setting of the internal configuration DIP switches. One changeover provides eleven multiformat channels covering HD-SDI (channels 1 to 6 only), SD-SDI,AES/EBU digital audio, analog black burst signal (PAL or NTSC), and tri-level sync signals. The delay for starting the error monitor at power up can be set to FAST or SLOW depending on the rise time of the system signal source being monitored. If a switch occurs from the primary signal to the backup signal, the channel that caused the problem is indicated on the front panel LED. The LT 444 can be configured in the system with a pair of the LT 443D Multiformat Video Generators. FEATURES:

• 11 User Configurable Channels
• Fault Channel 1-11 LED Indicators
• Selectable Delay Time for Monitor Start
• Sync Source Primary or Backup
• Selectable Determination Criteria of the Signal Level
• Auto Switching on Fault or Manual
• Multiformat Supports HD-SDI, SD-SDI, AES/EBU Digital Audio, HD Analog Tri-Level Sync, NTSC or PAL Analog Black Burst
• Fault Indicators and Reset for Primary and Backup
• Keylock Automatic Operation after 60 seconds