control is injected in this module. The module also
monitors the vertical sweep and horizontal flyback
signals, removes the 300-volt dc operating voltage
from the CRT, and extinguishes the STATUS light
when a failure occurs.
The vertical and horizontal sweep module
generates the vertical and horizontal sweeps used to
drive the CRT yoke. It provides these drive outputs to
the sweep heat sink module. The sweep module
receives feedback signals from the sweep heat sink
module to update and maintain the proper drive
The sweep heat sink module receives the vertical
and horizontal drive signals and provides the proper
level of yoke drive to the CRT. The sweep heat sink
module also sends feedback signals to the monitor
circuits in the vertical, sync, CRT protect, and
brightness control module.
The image presented on the video indicator is a
TV picture of the IR energy scanned by the receiver.
The video indicator is independent of the BITE
subsystems of the other WRAs. Only the STATUS
light and picture are indicative of a properly operating
Figure 6-27.-Video Indicator block diagram.