9600 Service Manual - gmecorp-usa.com

11 Video Path
VCR Output Video - When the Workstation is configured for post processing from the
internal VCR, the video leaves the VCR at the Video Out BNC connector. The video
signal enters the Workstation electronics box at BNC connector J1 located at the back of
the electronics box in the upper left hand corner. The VCR video signal enters the Video
Switching PCB at connector J4 on pin 3. A DC Restoration clamp (Q2) restores the
video sync tips to ground.
The incoming VCR video can be monitored at TP13 (VCR1). The video signal is sent to
the video switching matrix to mux chip U13 IN0 (pin 5). The video signal leaves U13 at
VOUT (pin 20). The video signal runs through another DC restoration clamp and is
buffered by U15. The video signal can be monitored at TP16 (A/D VIDEO). The video
signal is then sent back to the video switching matrix where it can be directed to, or
bypass a logarithmic amplifier (U46 and U26) which can be turned on for subtraction
modes.
The video signal is then sent back to the video switching matrix where it can be directed
to an anti-alias filter (U25 and U24). The anti-alias filter limits the video signal to 5 MHz.
The video signal from the anti-alias filter circuit can be monitored at TP18 (A/D VIDEO).
The video signal leaves the Video Switching PCB at connector J11 pin 5 and is sent to
the Image Processor PCB, connector P4 pin 5.