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The VTG Video Timing Generator provides up to ten video sync signals with which to synchronize CCTV cameras in the field. The VTG is intended to be used with the VTM Video Timing Meter to establish accurate timing of multiple CCTV cameras. A designated "Master Camera" is connected to the input of the VTG at the monitor Hub Sita. Up to ten coaxial cables leading to the other cameras are than connected to the VTG output connectors.
At this point a video sync pulse, locked to the Master Camera, is being
sent on the coax to each camera. The VTM meter is then taken to each camera
and the signal on the coax is compared to the camera output. The VTM then
measures the timing error of that camera and the camera is adjusted to
reduce that error to zero. The VTM is then taken to each camera in turn
and set to zero. The cameras are connected to their coax cables and the
VTQ removed. The cameras are now all perfectly synchronized so that they
may be switched without "rolling" the picture. Occasional routine tests,
using only the VTM to compare camera synchronization at the Hub can be
used to verify that synchronization has not been lost due to Electricians
changing power phases at the Power Panel.
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