Grass Valley 8941 - Manual (Page 20)

20 8941 Instruction Manual
Functional Description
In the Analog LPF (Low Pass Filter) and Output block the encoded analog
video passes through the LPF where alias artifacts are removed, and it then
goes to the output driver where the output level is set.
On power up, the Microcontroller performs a check-sum test and then
checks for video. If video is present, the Microcontroller configures the
encoder’s output to the type of video required (PAL or NTSC). The Micro-
controller then scans:
• DIP switches
• Changes in fault conditions
• Changes in video status
If any changes are detected, the Microcontroller takes action that requires a
variation in the video standard LEDs, module health line, or in the
encoder’s internal registers.
The 5V Switching Regulator block provides the + 5V for the module.
Power Supply Monitoring is provided to monitor +12V, –12V, and 5V DC
signals. It also alerts the health alarm signal if any voltage drops enough to
cause circuit malfunction.
Note Module health (alarm) monitoring requires that the Frame Controller or
8900NET module be installed in the frame.